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\title{A History of Science,\\
{\large Volume I, The Beginnings of Science}}


\author{Henry Smith Williams, M.D., LL.D.,\\
{\normalsize assisted by Edward H. Williams, M.D.}}

\maketitle
\noindent \vspace*{\stretch{1}}\\
This public domain (U.S.) text was scanned by Charles Keller with
OmniPage Professional OCR software. The Project Gutenberg edition
({}``1hsci10'') was subsequently converted to \LaTeX{} by means
of \textbf{GutenMark} software (version Jan 5 2003), and modified
(principally to correct formatting problems) by Ron Burkey. Numbered
endnotes have been replaced with footnotes, to conform to the style
of other books at sandroid.org. Greek text, which had been transliterated
into latin characters, has been transliterated back into greek characters;
the result of the double transliteration, I am sure, is highly inaccurate.
Report errors to info@sandroid.org.

\begin{description}
\item [Rev.~A,~02/16/03.]Proofing completed.
\item [Rev.~B,~02/22/03.]Various formatting corrections were made. Missing
illustrations were added from independent online sources. Illustrations
(possibly) scanned by S. A. Cohen.
\item [Rev.~C,~03/01/03.]Some illustrations were rotated to correct for
scanning errors, and one was redrawn. Many ligatures were corrected.
\end{description}
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 \frontmatter


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\mainmatter



\chapter*{\raggedright{}FOREWORD}

\addcontentsline{toc}{chapter}{FOREWORD}

\markboth{A HISTORY OF SCIENCE, BOOK I}{FOREWORD}

Should the story that is about to be unfolded be found to lack interest,
the writers must stand convicted of unpardonable lack of art. Nothing
but dulness in the telling could mar the story, for in itself it is
the record of the growth of those ideas that have made our race and
its civilization what they are; of ideas instinct with human interest,
vital with meaning for our race; fundamental in their influence on
human development; part and parcel of the mechanism of human thought
on the one hand, and of practical civilization on the other. Such
a phrase as {}``fundamental principles''\ may seem at first thought
a hard saying, but the idea it implies is less repellent than the
phrase itself, for the fundamental principles in question are so closely
linked with the present interests of every one of us that they lie
within the grasp of every average man and woman---nay, of every well-developed
boy and girl. These principles are not merely the stepping-stones
to culture, the prerequisites of knowledge---they are, in themselves,
an essential part of the knowledge of every cultivated person.

It is our task, not merely to show what these principles are, but
to point out how they have been discovered by our predecessors. We
shall trace the growth of these ideas from their first vague beginnings.
We shall see how vagueness of thought gave way to precision; how a
general truth, once grasped and formulated, was found to be a stepping-stone
to other truths. We shall see that there are no isolated facts, no
isolated principles, in nature; that each part of our story is linked
by indissoluble bands with that which goes before, and with that which
comes after. For the most part the discovery of this principle or
that in a given sequence is no accident. Galileo and Keppler must
precede Newton. Cuvier and Lyall must come before Darwin;---Which,
after all, is no more than saying that in our Temple of Science, as
in any other piece of architecture, the foundation must precede the
superstructure.

We shall best understand our story of the growth of science if we
think of each new principle as a stepping-stone which must fit into
its own particular niche; and if we reflect that the entire structure
of modern civilization would be different from what it is, and less
perfect than it is, had not that particular stepping-stone been found
and shaped and placed in position. Taken as a whole, our stepping-stones
lead us up and up towards the alluring heights of an acropolis of
knowledge, on which stands the Temple of Modern Science. The story
of the building of this wonderful structure is in itself fascinating
and beautiful.


\chapter*{\raggedright I.\ PREHISTORIC SCIENCE}

\addcontentsline{toc}{chapter}{I. PREHISTORIC SCIENCE}

\markboth{A HISTORY OF SCIENCE, BOOK I}{I. PREHISTORIC SCIENCE}

To speak of a prehistoric science may seem like a contradiction of
terms. The word prehistoric seems to imply barbarism, while science,
clearly enough, seems the outgrowth of civilization; but rightly considered,
there is no contradiction. For, on the one hand, man had ceased to
be a barbarian long before the beginning of what we call the historical
period; and, on the other hand, science, of a kind, is no less a precursor
and a cause of civilization than it is a consequent. To get this clearly
in mind, we must ask ourselves: What, then, is science? The word runs
glibly enough upon the tongue of our every-day speech, but it is not
often, perhaps, that they who use it habitually ask themselves just
what it means. Yet the answer is not difficult. A little attention
will show that science, as the word is commonly used, implies these
things: first, the gathering of knowledge through observation; second,
the classification of such knowledge, and through this classification,
the elaboration of general ideas or principles. In the familiar definition
of Herbert Spencer, science is organized knowledge.

Now it is patent enough, at first glance, that the veriest savage
must have been an observer of the phenomena of nature. But it may
not be so obvious that he must also have been a classifier of his
observations---an organizer of knowledge. Yet the more we consider
the case, the more clear it will become that the two methods are too
closely linked together to be dissevered. To observe outside phenomena
is not more inherent in the nature of the mind than to draw inferences
from these phenomena. A deer passing through the forest scents the
ground and detects a certain odor. A sequence of ideas is generated
in the mind of the deer. Nothing in the deer's experience can produce
that odor but a wolf; therefore the scientific inference is drawn
that wolves have passed that way. But it is a part of the deer's scientific
knowledge, based on previous experience, individual and racial, that
wolves are dangerous beasts; and so, combining direct observation
in the present with the application of a general principle based on
past experience, the deer reaches the very logical conclusion that
it may wisely turn about and run in another direction. All this implies,
essentially, a comprehension and use of scientific principles; and,
strange as it seems to speak of a deer as possessing scientific knowledge,
yet there is really no absurdity in the statement. The deer does possess
scientific knowledge; knowledge differing in degree only, not in kind,
from the knowledge of a Newton. Nor is the animal, within the range
of its intelligence, less logical, less scientific in the application
of that knowledge, than is the man. The animal that could not make
accurate scientific observations of its surroundings, and deduce accurate
scientific conclusions from them, would soon pay the penalty of its
lack of logic.

What is true of man's precursors in the animal scale is, of course,
true in a wider and fuller sense of man himself at the very lowest
stage of his development. Ages before the time which the limitations
of our knowledge force us to speak of as the dawn of history, man
had reached a high stage of development. As a social being, he had
developed all the elements of a primitive civilization. If, for convenience
of classification, we speak of his state as savage, or barbaric, we
use terms which, after all, are relative, and which do not shut off
our primitive ancestors from a tolerably close association with our
own ideals. We know that, even in the Stone Age, man had learned how
to domesticate animals and make them useful to him, and that he had
also learned to cultivate the soil. Later on, doubtless by slow and
painful stages, he attained those wonderful elements of knowledge
that enabled him to smelt metals and to produce implements of bronze,
and then of iron. Even in the Stone Age he was a mechanic of marvellous
skill, as any one of to-day may satisfy himself by attempting to duplicate
such an implement as a chipped arrow-head. And a barbarian who could
fashion an axe or a knife of bronze had certainly gone far in his
knowledge of scientific principles and their practical application.
The practical application was, doubtless, the only thought that our
primitive ancestor had in mind; quite probably the question as to
principles that might be involved troubled him not at all. Yet, in
spite of himself, he knew certain rudimentary principles of science,
even though he did not formulate them.

Let us inquire what some of these principles are. Such an inquiry
will, as it were, clear the ground for our structure of science. It
will show the plane of knowledge on which historical investigation
begins. Incidentally, perhaps, it will reveal to us unsuspected affinities
between ourselves and our remote ancestor. Without attempting anything
like a full analysis, we may note in passing, not merely what primitive
man knew, but what he did not know; that at least a vague notion may
be gained of the field for scientific research that lay open for historic
man to cultivate.

It must be understood that the knowledge of primitive man, as we are
about to outline it, is inferential. We cannot trace the development
of these principles, much less can we say who discovered them. Some
of them, as already suggested, are man's heritage from non-human ancestors.
Others can only have been grasped by him after he had reached a relatively
high stage of human development. But all the principles here listed
must surely have been parts of our primitive ancestor's knowledge
before those earliest days of Egyptian and Babylonian civilization,
the records of which constitute our first introduction to the so-called
historical period. Taken somewhat in the order of their probable discovery,
the scientific ideas of primitive man may be roughly listed as follows:\ 

1. Primitive man must have conceived that the earth is flat and of
limitless extent. By this it is not meant to imply that he had a distinct
conception of infinity, but, for that matter, it cannot be said that
any one to-day has a conception of infinity that could be called definite.
But, reasoning from experience and the reports of travellers, there
was nothing to suggest to early man the limit of the earth. He did,
indeed, find in his wanderings, that changed climatic conditions barred
him from farther progress; but beyond the farthest reaches of his
migrations, the seemingly flat land-surfaces and water-surfaces stretched
away unbroken and, to all appearances, without end. It would require
a reach of the philosophical imagination to conceive a limit to the
earth, and while such imaginings may have been current in the prehistoric
period, we can have no proof of them, and we may well postpone consideration
of man's early dreamings as to the shape of the earth until we enter
the historical epoch where we stand on firm ground.

2. Primitive man must, from a very early period, have observed that
the sun gives heat and light, and that the moon and stars seem to
give light only and no heat. It required but a slight extension of
this observation to note that the changing phases of the seasons were
associated with the seeming approach and recession of the sun. This
observation, however, could not have been made until man had migrated
from the tropical regions, and had reached a stage of mechanical development
enabling him to live in subtropical or temperate zones. Even then
it is conceivable that a long period must have elapsed before a direct
causal relation was felt to exist between the shifting of the sun
and the shifting of the seasons; because, as every one knows, the
periods of greatest heat in summer and greatest cold in winter usually
come some weeks after the time of the \textit{\emph{solstices}}. Yet,
the fact that these extremes of temperature are associated in some
way with the change of the sun's place in the heavens must, in time,
have impressed itself upon even a rudimentary intelligence. It is
hardly necessary to add that this is not meant to imply any definite
knowledge of the real meaning of, the seeming oscillations of the
sun. We shall see that, even at a relatively late period, the vaguest
notions were still in vogue as to the cause of the sun's changes of
position.

That the sun, moon, and stars move across the heavens must obviously
have been among the earliest scientific observations. It must not
be inferred, however, that this observation implied a necessary conception
of the complete revolution of these bodies about the earth. It is
unnecessary to speculate here as to how the primitive intelligence
conceived the transfer of the sun from the western to the eastern
horizon, to be effected each night, for we shall have occasion to
examine some historical speculations regarding this phenomenon. We
may assume, however, that the idea of the transfer of the heavenly
bodies beneath the earth (whatever the conception as to the form of
that body)\ must early have presented itself.

It required a relatively high development of the observing faculties,
yet a development which man must have attained ages before the historical
period, to note that the moon has a secondary motion, which leads
it to shift its relative position in the heavens, as regards the stars;
that the stars themselves, on the other hand, keep a fixed relation
as regards one another, with the notable exception of two or three
of the most brilliant members of the galaxy, the latter being the
bodies which came to be known finally as planets, or wandering stars.
The wandering propensities of such brilliant bodies as Jupiter and
Venus cannot well have escaped detection. We may safely assume, however,
that these anomalous motions of the moon and planets found no explanation
that could be called scientific until a relatively late period.

3. Turning from the heavens to the earth, and ignoring such primitive
observations as that of the distinction between land and water, we
may note that there was one great scientific law which must have forced
itself upon the attention of primitive man. This is the law of universal
terrestrial gravitation. The word gravitation suggests the name of
Newton, and it may excite surprise to hear a knowledge of gravitation
ascribed to men who preceded that philosopher by, say, twenty-five
or fifty thousand years. Yet the slightest consideration of the facts
will make it clear that the great central law that all heavy bodies
fall directly towards the earth, cannot have escaped the attention
of the most primitive intelligence. The arboreal habits of our primitive
ancestors gave opportunities for constant observation of the practicalities
of this law. And, so soon as man had developed the mental capacity
to formulate ideas, one of the earliest ideas must have been the conception,
however vaguely phrased in words, that all unsupported bodies fall
towards the earth. The same phenomenon being observed to operate on
water-surfaces, and no alteration being observed in its operation
in different portions of man's habitat, the most primitive wanderer
must have come to have full faith in the universal action of the observed
law of gravitation. Indeed, it is inconceivable that he can have imagined
a place on the earth where this law does not operate. On the other
hand, of course, he never grasped the conception of the operation
of this law beyond the close proximity of the earth. To extend the
reach of gravitation out to the moon and to the stars, including within
its compass every particle of matter in the universe, was the work
of Newton, as we shall see in due course. Meantime we shall better
understand that work if we recall that the mere local fact of terrestrial
gravitation has been the familiar knowledge of all generations of
men. It may further help to connect us in sympathy with our primeval
ancestor if we recall that in the attempt to explain this fact of
terrestrial gravitation Newton made no advance, and we of to-day are
scarcely more enlightened than the man of the Stone Age. Like the
man of the Stone Age, we know that an arrow shot into the sky falls
back to the earth. We can calculate, as he could not do, the arc it
will describe and the exact speed of its fall; but as to why it returns
to earth at all, the greatest philosopher of to-day is almost as much
in the dark as was the first primitive bowman that ever made the experiment.

%
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\noindent \begin{center}\noun{\small Man and the Anthropoid Apes}\end{center}{\small \par}

\noindent \emph{\footnotesize Montage of a prehistoric man (}{\footnotesize Pithecanthropos
erectus}\emph{\footnotesize ) next to a gorilla, and another simian;
above them are pictured their corresponding skulls.} {\footnotesize }
\end{figure}
Other physical facts going to make up an elementary science of mechanics,
that were demonstratively known to prehistoric man, were such as these:
the rigidity of solids and the mobility of liquids; the fact that
changes of temperature transform solids to liquids and vice versa---that
heat, for example, melts copper and even iron, and that cold congeals
water; and the fact that friction, as illustrated in the rubbing together
of two sticks, may produce heat enough to cause a fire. The rationale
of this last experiment did not receive an explanation until about
the beginning of the nineteenth century of our own era. But the experimental
fact was so well known to prehistoric man that he employed this method,
as various savage tribes employ it to this day, for the altogether
practical purpose of making a fire; just as he employed his practical
knowledge of the mutability of solids and liquids in smelting ores,
in alloying copper with tin to make bronze, and in casting this alloy
in molds to make various implements and weapons. Here, then, were
the germs of an elementary science of physics. Meanwhile such observations
as that of the solution of salt in water may be considered as giving
a first lesson in chemistry, but beyond such altogether rudimentary
conceptions chemical knowledge could not have gone---unless, indeed,
the practical observation of the effects of fire be included; nor
can this well be overlooked, since scarcely another single line of
practical observation had a more direct influence in promoting the
progress of man towards the heights of civilization.

4. In the field of what we now speak of as biological knowledge, primitive
man had obviously the widest opportunity for practical observation.
We can hardly doubt that man attained, at an early day, to that conception
of identity and of difference which Plato places at the head of his
metaphysical system. We shall urge presently that it is precisely
such general ideas as these that were man's earliest inductions from
observation, and hence that came to seem the most universal and {}``innate''\ ideas
of his mentality. It is quite inconceivable, for example, that even
the most rudimentary intelligence that could be called human could
fail to discriminate between living things and, let us say, the rocks
of the earth. The most primitive intelligence, then, must have made
a tacit classification of the natural objects about it into the grand
divisions of animate and inanimate nature. Doubtless the nascent scientist
may have imagined life animating many bodies that we should call inanimate---such
as the sun, wandering planets, the winds, and lightning; and, on the
other hand, he may quite likely have relegated such objects as trees
to the ranks of the non-living; but that he recognized a fundamental
distinction between, let us say, a wolf and a granite bowlder we cannot
well doubt. A step beyond this---a step, however, that may have required
centuries or millenniums in the taking---must have carried man to
a plane of intelligence from which a primitive Aristotle or Linn\ae{}us
was enabled to note differences and resemblances connoting such groups
of things as fishes, birds, and furry beasts. This conception, to
be sure, is an abstraction of a relatively high order. We know that
there are savage races to-day whose language contains no word for
such an abstraction as bird or tree. We are bound to believe, then,
that there were long ages of human progress during which the highest
man had attained no such stage of abstraction; but, on the other hand,
it is equally little in question that this degree of mental development
had been attained long before the opening of our historical period.
The primeval man, then, whose scientific knowledge we are attempting
to predicate, had become, through his conception of fishes, birds,
and hairy animals as separate classes, a scientific zoologist of relatively
high attainments.

In the practical field of medical knowledge, a certain stage of development
must have been reached at a very early day. Even animals pick and
choose among the vegetables about them, and at times seek out certain
herbs quite different from their ordinary food, practising a sort
of instinctive therapeutics. The cat's fondness for catnip is a case
in point. The most primitive man, then, must have inherited a racial
or instinctive knowledge of the medicinal effects of certain herbs;
in particular he must have had such elementary knowledge of toxicology
as would enable him to avoid eating certain poisonous berries. Perhaps,
indeed, we are placing the effect before the cause to some extent;
for, after all, the animal system possesses marvellous powers of adaption,
and there is perhaps hardly any poisonous vegetable which man might
not have learned to eat without deleterious effect, provided the experiment
were made gradually. To a certain extent, then, the observed poisonous
effects of numerous plants upon the human system are to be explained
by the fact that our ancestors have avoided this particular vegetable.
Certain fruits and berries might have come to have been a part of
man's diet, had they grown in the regions he inhabited at an early
day, which now are poisonous to his system. This thought, however,
carries us too far afield. For practical purposes, it suffices that
certain roots, leaves, and fruits possess principles that are poisonous
to the human system, and that unless man had learned in some way to
avoid these, our race must have come to disaster. In point of fact,
he did learn to avoid them; and such evidence implied, as has been
said, an elementary knowledge of toxicology.

Coupled with this knowledge of things dangerous to the human system,
there must have grown up, at a very early day, a belief in the remedial
character of various vegetables as agents to combat disease. Here,
of course, was a rudimentary therapeutics, a crude principle of an
empirical art of medicine. As just suggested, the lower order of animals
have an instinctive knowledge that enables them to seek out remedial
herbs (though we probably exaggerate the extent of this instinctive
knowledge); and if this be true, man must have inherited from his
prehuman ancestors this instinct along with the others. That he extended
this knowledge through observation and practice, and came early to
make extensive use of drugs in the treatment of disease, is placed
beyond cavil through the observation of the various existing barbaric
tribes, nearly all of whom practice elaborate systems of therapeutics.
We shall have occasion to see that even within historic times the
particular therapeutic measures employed were often crude, and, as
we are accustomed to say, unscientific; but even the crudest of them
are really based upon scientific principles, inasmuch as their application
implies the deduction of principles of action from previous observations.
Certain drugs are applied to appease certain symptoms of disease because
in the belief of the medicine-man such drugs have proved beneficial
in previous similar cases.

All this, however, implies an appreciation of the fact that man is
subject to {}``natural''\ diseases, and that if these diseases
are not combated, death may result. But it should be understood that
the earliest man probably had no such conception as this. Throughout
all the ages of early development, what we call {}``natural''\ disease
and {}``natural''\ death meant the onslaught of a tangible enemy.
A study of this question leads us to some very curious inferences.
The more we look into the matter the more the thought forces itself
home to us that the idea of natural death, as we now conceive it,
came to primitive man as a relatively late scientific induction. This
thought seems almost startling, so axiomatic has the conception {}``man
is mortal''\ come to appear. Yet a study of the ideas of existing
savages, combined with our knowledge of the point of view from which
historical peoples regard disease, make it more probable that the
primitive conception of human life did not include the idea of necessary
death. We are told that the Australian savage who falls from a tree
and breaks his neck is not regarded as having met a natural death,
but as having been the victim of the magical practices of the {}``medicine-man''\ of
some neighboring tribe. Similarly, we shall find that the Egyptian
and the Babylonian of the early historical period conceived illness
as being almost invariably the result of the machinations of an enemy.
One need but recall the superstitious observances of the Middle Ages,
and the yet more recent belief in witchcraft, to realize how generally
disease has been personified as a malicious agent invoked by an unfriendly
mind. Indeed, the phraseology of our present-day speech is still reminiscent
of this; as when, for example, we speak of an {}``attack of fever,''\ and
the like.

When, following out this idea, we picture to ourselves the conditions
under which primitive man lived, it will be evident at once how relatively
infrequent must have been his observation of what we usually term
natural death. His world was a world of strife; he lived by the chase;
he saw animals kill one another; he witnessed the death of his own
fellows at the hands of enemies. Naturally enough, then, when a member
of his family was {}``struck down''\ by invisible agents, he ascribed
this death also to violence, even though the offensive agent was concealed.
Moreover, having very little idea of the lapse of time---being quite
unaccustomed, that is, to reckon events from any fixed era---primitive
man cannot have gained at once a clear conception of age as applied
to his fellows. Until a relatively late stage of development made
tribal life possible, it cannot have been usual for man to have knowledge
of his grandparents; as a rule he did not know his own parents after
he had passed the adolescent stage and had been turned out upon the
world to care for himself. If, then, certain of his fellow-beings
showed those evidences of infirmity which we ascribe to age, it did
not necessarily follow that he saw any association between such infirmities
and the length of time which those persons had lived. The very fact
that some barbaric nations retain the custom of killing the aged and
infirm, in itself suggests the possibility that this custom arose
before a clear conception had been attained that such drags upon the
community would be removed presently in the natural order of things.
To a person who had no clear conception of the lapse of time and no
preconception as to the limited period of man's life, the infirmities
of age might very naturally be ascribed to the repeated attacks of
those inimical powers which were understood sooner or later to carry
off most members of the race. And coupled with this thought would
go the conception that inasmuch as some people through luck had escaped
the vengeance of all their enemies for long periods, these same individuals
might continue to escape for indefinite periods of the future. There
were no written records to tell primeval man of events of long ago.
He lived in the present, and his sweep of ideas scarcely carried him
back beyond the limits of his individual memory. But memory is observed
to be fallacious. It must early have been noted that some people recalled
events which other participants in them had quite forgotten, and it
may readily enough have been inferred that those members of the tribe
who spoke of events which others could not recall were merely the
ones who were gifted with the best memories. If these reached a period
when their memories became vague, it did not follow that their recollections
had carried them back to the beginnings of their lives. Indeed, it
is contrary to all experience to believe that any man remembers all
the things he has once known, and the observed fallaciousness and
evanescence of memory would thus tend to substantiate rather than
to controvert the idea that various members of a tribe had been alive
for an indefinite period.

Without further elaborating the argument, it seems a justifiable inference
that the first conception primitive man would have of his own life
would not include the thought of natural death, but would, conversely,
connote the vague conception of endless life. Our own ancestors, a
few generations removed, had not got rid of this conception, as the
perpetual quest of the spring of eternal youth amply testifies. A
naturalist of our own day has suggested that perhaps birds never die
except by violence. The thought, then, that man has a term of years
beyond which {}``in the nature of things,''\ as the saying goes,
he may not live, would have dawned but gradually upon the developing
intelligence of successive generations of men; and we cannot feel
sure that he would fully have grasped the conception of a {}``natural''\ termination
of human life until he had shaken himself free from the idea that
disease is always the result of the magic practice of an enemy. Our
observation of historical man in antiquity makes it somewhat doubtful
whether this conception had been attained before the close of the
prehistoric period. If it had, this conception of the mortality of
man was one of the most striking scientific inductions to which prehistoric
man attained. Incidentally, it may be noted that the conception of
eternal life for the human body being a more primitive idea than the
conception of natural death, the idea of the immortality of the spirit
would be the most natural of conceptions. The immortal spirit, indeed,
would be but a correlative of the immortal body, and the idea which
we shall see prevalent among the Egyptians that the soul persists
only as long as the body is intact---the idea upon which the practice
of mummifying the dead depended---finds a ready explanation. But this
phase of the subject carries us somewhat afield. For our present purpose
it suffices to have pointed out that the conception of man's mortality---a
conception which now seems of all others the most natural and {}``innate''---was
in all probability a relatively late scientific induction of our primitive
ancestors.

5. Turning from the consideration of the body to its mental complement,
we are forced to admit that here, also, our primitive man must have
made certain elementary observations that underlie such sciences as
psychology, mathematics, and political economy. The elementary emotions
associated with hunger and with satiety, with love and with hatred,
must have forced themselves upon the earliest intelligence that reached
the plane of conscious self-observation. The capacity to count, at
least to the number four or five, is within the range of even animal
intelligence. Certain savages have gone scarcely farther than this;
but our primeval ancestor, who was forging on towards civilization,
had learned to count his fingers and toes, and to number objects about
him by fives and tens in consequence, before he passed beyond the
plane of numerous existing barbarians. How much beyond this he had
gone we need not attempt to inquire; but the relatively high development
of mathematics in the early historical period suggests that primeval
man had attained a not inconsiderable knowledge of numbers. The humdrum
vocation of looking after a numerous progeny must have taught the
mother the rudiments of addition and subtraction; and the elements
of multiplication and division are implied in the capacity to carry
on even the rudest form of barter, such as the various tribes must
have practised from an early day.

As to political ideas, even the crudest tribal life was based on certain
conceptions of ownership, at least of tribal ownership, and the application
of the principle of likeness and difference to which we have already
referred. Each tribe, of course, differed in some regard from other
tribes, and the recognition of these differences implied in itself
a political classification. A certain tribe took possession of a particular
hunting-ground, which became, for the time being, its home, and over
which it came to exercise certain rights. An invasion of this territory
by another tribe might lead to war, and the banding together of the
members of the tribe to repel the invader implied both a recognition
of communal unity and a species of prejudice in favor of that community
that constituted a primitive patriotism. But this unity of action
in opposing another tribe would not prevent a certain rivalry of interest
between the members of the same tribe, which would show itself more
and more prominently as the tribe increased in size. The association
of two or more persons implies, always, the ascendency of some and
the subordination of others. Leadership and subordination are necessary
correlatives of difference of physical and mental endowment, and rivalry
between leaders would inevitably lead to the formation of primitive
political parties. With the ultimate success and ascendency of one
leader, who secures either absolute power or power modified in accordance
with the advice of subordinate leaders, we have the germs of an elaborate
political system---an embryo science of government.

Meanwhile, the very existence of such a community implies the recognition
on the part of its members of certain individual rights, the recognition
of which is essential to communal harmony. The right of individual
ownership of the various articles and implements of every-day life
must be recognized, or all harmony would be at an end. Certain rules
of justice---primitive laws---must, by common consent, give protection
to the weakest members of the community. Here are the rudiments of
a system of ethics. It may seem anomalous to speak of this primitive
morality, this early recognition of the principles of right and wrong,
as having any relation to science. Yet, rightly considered, there
is no incongruity in such a citation. There cannot well be a doubt
that the adoption of those broad principles of right and wrong which
underlie the entire structure of modern civilization was due to scientific
induction,---in other words, to the belief, based on observation and
experience, that the principles implied were essential to communal
progress. He who has scanned the pageant of history knows how often
these principles seem to be absent in the intercourse of men and nations.
Yet the ideal is always there as a standard by which all deeds are
judged.

It would appear, then, that the entire superstructure of later science
had its foundation in the knowledge and practice of prehistoric man.
The civilization of the historical period could not have advanced
as it has had there not been countless generations of culture back
of it. The new principles of science could not have been evolved had
there not been great basal principles which ages of unconscious experiment
had impressed upon the mind of our race. Due meed of praise must be
given, then, to our primitive ancestor for his scientific accomplishments;
but justice demands that we should look a little farther and consider
the reverse side of the picture. We have had to do, thus far, chiefly
with the positive side of accomplishment. We have pointed out what
our primitive ancestor knew, intimating, perhaps, the limitations
of his knowledge; but we have had little to say of one all-important
feature of his scientific theorizing. The feature in question is based
on the highly scientific desire and propensity to find explanations
for the phenomena of nature. Without such desire no progress could
be made. It is, as we have seen, the generalizing from experience
that constitutes real scientific progress; and yet, just as most other
good things can be overdone, this scientific propensity may be carried
to a disastrous excess.

Primeval man did not escape this danger. He observed, he reasoned,
he found explanations; but he did not always discriminate as to the
logicality of his reasonings. He failed to recognize the limitations
of his knowledge. The observed uniformity in the sequence of certain
events impressed on his mind the idea of cause and effect. Proximate
causes known, he sought remoter causes; childlike, his inquiring mind
was always asking, Why?\ and, childlike, he demanded an explicit
answer. If the forces of nature seemed to combat him, if wind and
rain opposed his progress and thunder and lightning seemed to menace
his existence, he was led irrevocably to think of those human foes
who warred with him, and to see, back of the warfare of the elements,
an inscrutable malevolent intelligence which took this method to express
its displeasure. But every other line of scientific observation leads
equally, following back a sequence of events, to seemingly causeless
beginnings. Modern science can explain the lightning, as it can explain
a great number of the mysteries which the primeval intelligence could
not penetrate. But the primordial man could not wait for the revelations
of scientific investigation: he must vault at once to a final solution
of all scientific problems. He found his solution by peopling the
world with invisible forces, anthropomorphic in their conception,
like himself in their thought and action, differing only in the limitations
of their powers. His own dream existence gave him seeming proof of
the existence of an alter ego, a spiritual portion of himself that
could dissever itself from his body and wander at will; his scientific
inductions seemed to tell him of a world of invisible beings, capable
of influencing him for good or ill. From the scientific exercise of
his faculties he evolved the all-encompassing generalizations of invisible
and all-powerful causes back of the phenomena of nature. These generalizations,
early developed and seemingly supported by the observations of countless
generations, came to be among the most firmly established scientific
inductions of our primeval ancestor. They obtained a hold upon the
mentality of our race that led subsequent generations to think of
them, sometimes to speak of them, as {}``innate''\ ideas. The observations
upon which they were based are now, for the most part, susceptible
of other interpretations; but the old interpretations have precedent
and prejudice back of them, and they represent ideas that are more
difficult than almost any others to eradicate. Always, and everywhere,
superstitions based upon unwarranted early scientific deductions have
been the most implacable foes to the progress of science. Men have
built systems of philosophy around their conception of anthropomorphic
deities; they have linked to these systems of philosophy the allied
conception of the immutability of man's spirit, and they have asked
that scientific progress should stop short at the brink of these systems
of philosophy and accept their dictates as final. Yet there is not
to-day in existence, and there never has been, one jot of scientific
evidence for the existence of these intangible anthropomorphic powers
back of nature that is not susceptible of scientific challenge and
of more logical interpretation. In despite of which the superstitious
beliefs are still as firmly fixed in the minds of a large majority
of our race as they were in the mind of our prehistoric ancestor.
The fact of this baleful heritage must not be forgotten in estimating
the debt of gratitude which historic man owes to his barbaric predecessor.


\chapter*{\raggedright II. EGYPTIAN SCIENCE}

\addcontentsline{toc}{chapter}{II. EGYPTIAN SCIENCE}

\markboth{A HISTORY OF SCIENCE, BOOK I}{II. EGYPTIAN SCIENCE}

In the previous chapter we have purposely refrained from referring
to any particular tribe or race of historical man. Now, however, we
are at the beginnings of national existence, and we have to consider
the accomplishments of an individual race; or rather, perhaps, of
two or more races that occupied successively the same geographical
territory. But even now our studies must for a time remain very general;
we shall see little or nothing of the deeds of individual scientists
in the course of our study of Egyptian culture. We are still, it must
be understood, at the beginnings of history; indeed, we must first
bridge over the gap from the prehistoric before we may find ourselves
fairly on the line of march of historical science.

At the very outset we may well ask what constitutes the distinction
between prehistoric and historic epochs---a distinction which has
been constantly implied in much that we have said. The reply savors
somewhat of vagueness. It is a distinction having to do, not so much
with facts of human progress as with our interpretation of these facts.
When we speak of the dawn of history we must not be understood to
imply that, at the period in question, there was any sudden change
in the intellectual status of the human race or in the status of any
individual tribe or nation of men. What we mean is that modern knowledge
has penetrated the mists of the past for the period we term historical
with something more of clearness and precision than it has been able
to bring to bear upon yet earlier periods. New accessions of knowledge
may thus shift from time to time the bounds of the so-called historical
period. The clearest illustration of this is furnished by our interpretation
of Egyptian history. Until recently the biblical records of the Hebrew
captivity or service, together with the similar account of Josephus,
furnished about all that was known of Egyptian history even of so
comparatively recent a time as that of Ramses II.\ (fifteenth century
B.C.), and from that period on there was almost a complete gap until
the story was taken up by the Greek historians Herodotus and Diodorus.
It is true that the king-lists of the Alexandrian historian, Manetho,
were all along accessible in somewhat garbled copies. But at best
they seemed to supply unintelligible lists of names and dates which
no one was disposed to take seriously. That they were, broadly speaking,
true historical records, and most important historical records at
that, was not recognized by modern scholars until fresh light had
been thrown on the subject from altogether new sources.

These new sources of knowledge of ancient history demand a moment's
consideration. They are all-important because they have been the means
of extending the historical period of Egyptian history (using the
word history in the way just explained)\ by three or four thousand
years. As just suggested, that historical period carried the scholarship
of the early nineteenth century scarcely beyond the fifteenth century
B.C., but to-day's vision extends with tolerable clearness to about
the middle of the fifth millennium B.C. This change has been brought
about chiefly through study of the Egyptian hieroglyphics. These hieroglyphics
constitute, as we now know, a highly developed system of writing;
a system that was practised for some thousands of years, but which
fell utterly into disuse in the later Roman period, and the knowledge
of which passed absolutely from the mind of man. For about two thousand
years no one was able to read, with any degree of explicitness, a
single character of this strange script, and the idea became prevalent
that it did not constitute a real system of writing, but only a more
or less barbaric system of religious symbolism. The falsity of this
view was shown early in the nineteenth century when Dr.\ Thomas Young
was led, through study of the famous trilingual inscription of the
Rosetta stone, to make the first successful attempt at clearing up
the mysteries of the hieroglyphics.

This is not the place to tell the story of his fascinating discoveries
and those of his successors. That story belongs to nineteenth-century
science, not to the science of the Egyptians. Suffice it here that
Young gained the first clew to a few of the phonetic values of the
Egyptian symbols, and that the work of discovery was carried on and
vastly extended by the Frenchman Champollion, a little later, with
the result that the firm foundations of the modern science of Egyptology
were laid. Subsequently such students as Rosellini the Italian, Lepsius
the German, and Wilkinson the Englishman, entered the field, which
in due course was cultivated by De Rouge in France and Birch in England,
and by such distinguished latter-day workers as Chabas, Mariette,
Maspero, Amelineau, and De Morgan among the Frenchmen; Professor Petrie
and Dr.\ Budge in England; and Brugsch Pasha and Professor Erman
in Germany, not to mention a large coterie of somewhat less familiar
names. These men working, some of them in the field of practical exploration,
some as students of the Egyptian language and writing, have restored
to us a tolerably precise knowledge of the history of Egypt from the
time of the first historical king, Mena, whose date is placed at about
the middle of the fifth century B.C.%
\footnote{The date is probably a misprint; 3100 B.C. would be more accurate---R.B.%
} We know not merely the names of most of the subsequent rulers, but
some thing of the deeds of many of them; and, what is vastly more
important, we know, thanks to the modern interpretation of the old
literature, many things concerning the life of the people, and in
particular concerning their highest culture, their methods of thought,
and their scientific attainments, which might well have been supposed
to be past finding out. Nor has modern investigation halted with the
time of the first kings; the recent explorations of such arch\ae{}ologists
as Amelineau, De Morgan, and Petrie have brought to light numerous
remains of what is now spoken of as the predynastic period---a period
when the inhabitants of the Nile Valley used implements of chipped
stone, when their pottery was made without the use of the potter's
wheel, and when they buried their dead in curiously cramped attitudes
without attempt at mummification. These aboriginal inhabitants of
Egypt cannot perhaps with strict propriety be spoken of as living
within the historical period, since we cannot date their relics with
any accuracy. But they give us glimpses of the early stages of civilization
upon which the Egyptians of the dynastic period were to advance.

It is held that the nascent civilization of these Egyptians of the
Neolithic, or late Stone Age, was overthrown by the invading hosts
of a more highly civilized race which probably came from the East,
and which may have been of a Semitic stock. The presumption is that
this invading people brought with it a knowledge of the arts of war
and peace, developed or adopted in its old home. The introduction
of these arts served to bridge somewhat suddenly, so far as Egypt
is concerned, that gap between the prehistoric and the historic stage
of culture to which we have all along referred. The essential structure
of that bridge, let it now be clearly understood, consisted of a single
element. That element is the capacity to make written records: a knowledge
of the art of writing. Clearly understood, it is this element of knowledge
that forms the line bounding the historical period. Numberless mementos
are in existence that tell of the intellectual activities of prehistoric
man; such mementos as flint implements, pieces of pottery, and fragments
of bone, inscribed with pictures that may fairly be spoken of as works
of art; but so long as no written word accompanies these records,
so long as no name of king or scribe comes down to us, we feel that
these records belong to the domain of arch\ae{}ology rather than
to that of history. Yet it must be understood all along that these
two domains shade one into the other and, it has already been urged,
that the distinction between them is one that pertains rather to modern
scholarship than to the development of civilization itself. Bearing
this distinction still in mind, and recalling that the historical
period, which is to be the field of our observation throughout the
rest of our studies, extends for Egypt well back into the fifth millennium
B.C., let us briefly review the practical phases of that civilization
to which the Egyptian had attained before the beginning of the dynastic
period. Since theoretical science is everywhere linked with the mechanical
arts, this survey will give us a clear comprehension of the field
that lies open for the progress of science in the long stages of historical
time upon which we are just entering.

We may pass over such rudimentary advances in the direction of civilization
as are implied in the use of articulate language, the application
of fire to the uses of man, and the systematic making of dwellings
of one sort or another, since all of these are stages of progress
that were reached very early in the prehistoric period. What more
directly concerns us is to note that a really high stage of mechanical
development had been reached before the dawnings of Egyptian history
proper. All manner of household utensils were employed; the potter's
wheel aided in the construction of a great variety of earthen vessels;
weaving had become a fine art, and weapons of bronze, including axes,
spears, knives, and arrow-heads, were in constant use. Animals had
long been domesticated, in particular the dog, the cat, and the ox;
the horse was introduced later from the East. The practical arts of
agriculture were practised almost as they are at the present day in
Egypt, there being, of course, the same dependence then as now upon
the inundations of the Nile.

As to government, the Egyptian of the first dynasty regarded his king
as a demi-god to be actually deified after his death, and this point
of view was not changed throughout the stages of later Egyptian history.
In point of art, marvellous advances upon the skill of the prehistoric
man had been made, probably in part under Asiatic influences, and
that unique style of stilted yet expressive drawing had come into
vogue, which was to be remembered in after times as typically Egyptian.
More important than all else, our Egyptian of the earliest historical
period was in possession of the art of writing. He had begun to make
those specific records which were impossible to the man of the Stone
Age, and thus he had entered fully upon the way of historical progress
which, as already pointed out, has its very foundation in written
records. From now on the deeds of individual kings could find specific
record. It began to be possible to fix the chronology of remote events
with some accuracy; and with this same fixing of chronologies came
the advent of true history. The period which precedes what is usually
spoken of as the first dynasty in Egypt is one into which the present-day
searcher is still able to see but darkly. The evidence seems to suggest
than an invasion of relatively cultured people from the East overthrew,
and in time supplanted, the Neolithic civilization of the Nile Valley.
It is impossible to date this invasion accurately, but it cannot well
have been later than the year 5000 B.C., and it may have been a great
many centuries earlier than this. Be the exact dates what they may,
we find the Egyptian of the fifth millennium B.C.\ in full possession
of a highly organized civilization.

All subsequent ages have marvelled at the pyramids, some of which
date from about the year 4000 B.C., though we may note in passing
that these dates must not be taken too literally. The chronology of
ancient Egypt cannot as yet be fixed with exact accuracy, but the
disagreements between the various students of the subject need give
us little concern. For our present purpose it does not in the least
matter whether the pyramids were built three thousand or four thousand
years before the beginning of our era. It suffices that they date
back to a period long antecedent to the beginnings of civilization
in Western Europe. They prove that the Egyptian of that early day
had attained a knowledge of practical mechanics which, even from the
twentieth-century point of view, is not to be spoken of lightly. It
has sometimes been suggested that these mighty pyramids, built as
they are of great blocks of stone, speak for an almost miraculous
knowledge on the part of their builders; but a saner view of the conditions
gives no warrant for this thought. Diodoras, the Sicilian, in his
famous \emph{World's History}, written about the beginning of our
era, explains the building of the pyramids by suggesting that great
quantities of earth were piled against the side of the rising structure
to form an inclined plane up which the blocks of stone were dragged.
He gives us certain figures, based, doubtless, on reports made to
him by Egyptian priests, who in turn drew upon the traditions of their
country, perhaps even upon written records no longer preserved. He
says that one hundred and twenty thousand men were employed in the
construction of the largest pyramid, and that, notwithstanding the
size of this host of workers, the task occupied twenty years. We must
not place too much dependence upon such figures as these, for the
ancient historians are notoriously given to exaggeration in recording
numbers; yet we need not doubt that the report given by Diodorus is
substantially accurate in its main outlines as to the method through
which the pyramids were constructed. A host of men putting their added
weight and strength to the task, with the aid of ropes, pulleys, rollers,
and levers, and utilizing the principle of the inclined plane, could
undoubtedly move and elevate and place in position the largest blocks
that enter into the pyramids or---what seems even more wonderful---the
most gigantic obelisks, without the aid of any other kind of mechanism
or of any more occult power. The same hands could, as Diodorus suggests,
remove all trace of the debris of construction and leave the pyramids
and obelisks standing in weird isolation, as if sprung into being
through a miracle.


\section*{\raggedright ASTRONOMICAL SCIENCE}

\addcontentsline{toc}{section}{ASTRONOMICAL SCIENCE}

It has been necessary to bear in mind these phases of practical civilization
because much that we know of the purely scientific attainments of
the Egyptians is based upon modern observation of their pyramids and
temples. It was early observed, for example, that the pyramids are
obviously oriented as regards the direction in which they face, in
strict accordance with some astronomical principle. Early in the nineteenth
century the Frenchman Biot made interesting studies in regard to this
subject, and a hundred years later, in our own time, Sir Joseph Norman
Lockyer, following up the work of various intermediary observers,
has given the subject much attention, making it the central theme
of his work on \emph{The Dawn of Astronomy}.%
\footnote{Sir J.\ Norman Lockyer, \emph{The Dawn of Astronomy}; a study of
the temple worship and mythology of the ancient Egyptians, London,
1894.%
} Lockyer's researches make it clear that in the main the temples of
Egypt were oriented with reference to the point at which the sun rises
on the day of the summer solstice. The time of the solstice had peculiar
interest for the Egyptians, because it corresponded rather closely
with the time of the rising of the Nile. The floods of that river
appear with very great regularity; the on-rushing tide reaches the
region of Heliopolis and Memphis almost precisely on the day of the
summer solstice. The time varies at different stages of the river's
course, but as the civilization of the early dynasties centred at
Memphis, observations made at this place had widest vogue.

Considering the all-essential character of the Nile floods---without
which civilization would be impossible in Egypt---it is not strange
that the time of their appearance should be taken as marking the beginning
of a new year. The fact that their coming coincides with the solstice
makes such a division of the calendar perfectly natural. In point
of fact, from the earliest periods of which records have come down
to us, the new year of the Egyptians dates from the summer solstice.
It is certain that from the earliest historical periods the Egyptians
were aware of the approximate length of the year. It would be strange
were it otherwise, considering the ease with which a record of days
could be kept from Nile flood to Nile flood, or from solstice to solstice.
But this, of course, applies only to an approximate count. There is
some reason to believe that in the earliest period the Egyptians made
this count only 360 days. The fact that their year was divided into
twelve months of thirty days each lends color to this belief; but,
in any event, the mistake was discovered in due time and a partial
remedy was applied through the interpolation of a {}``little month''\ of
five days between the end of the twelfth month and the new year. This
nearly but not quite remedied the matter. What it obviously failed
to do was to take account of that additional quarter of a day which
really rounds out the actual year.

It would have been a vastly convenient thing for humanity had it chanced
that the earth had so accommodated its rotary motion with its speed
of transit about the sun as to make its annual flight in precisely
360 days. Twelve lunar months of thirty days each would then have
coincided exactly with the solar year, and most of the complexities
of the calendar, which have so puzzled historical students, would
have been avoided; but, on the other hand, perhaps this very simplicity
would have proved detrimental to astronomical science by preventing
men from searching the heavens as carefully as they have done. Be
that as it may, the complexity exists. The actual year of three hundred
and sixty-five and (about)\ one-quarter days cannot be divided evenly
into months, and some such expedient as the intercalation of days
here and there is essential, else the calendar will become absolutely
out of harmony with the seasons.

In the case of the Egyptians, the attempt at adjustment was made,
as just noted, by the introduction of the five days, constituting
what the Egyptians themselves termed {}``the five days over and above
the year.'' These so-called epagomenal days were undoubtedly introduced
at a very early period. Maspero holds that they were in use before
the first Thinite dynasty, citing in evidence the fact that the legend
of Osiris explains these days as having been created by the god Thot
in order to permit \textit{\emph{Nuit}} to give birth to all her children;
this expedient being necessary to overcome a ban which had been pronounced
against \textit{\emph{Nuit}}, according to which she could not give
birth to children on any day of the year. But, of course, the five
additional days do not suffice fully to rectify the calendar. There
remains the additional quarter of a day to be accounted for. This,
of course, amounts to a full day every fourth year. We shall see that
later Alexandrian science hit upon the expedient of adding a day to
every fourth year; an expedient which the Julian calendar adopted
and which still gives us our familiar leap-year. But, unfortunately,
the ancient Egyptian failed to recognize the need of this additional
day, or if he did recognize it he failed to act on his knowledge,
and so it happened that, starting somewhere back in the remote past
with a new year's day that coincided with the inundation of the Nile,
there was a constantly shifting maladjustment of calendar and seasons
as time went on.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc36}\end{center}

\noindent \begin{center}\noun{\small The Sun Embarking for his Daily
Journey Through Egypt}\end{center}{\small \par}

\noindent \emph{\footnotesize (Redrawn from Rosellini,} {\footnotesize Monumenta
del Culto}\emph{\footnotesize , No.\ I., taken from one of the scenes
represented upon the architraves of the pronaos at Edfû.)}
\end{figure}
The Egyptian seasons, it should be explained, were three in number:
the season of the inundation, the season of the seed-time, and the
season of the harvest; each season being, of course, four months in
extent. Originally, as just mentioned, the season of the inundations
began and coincided with the actual time of inundation. The more precise
fixing of new year's day was accomplished through observation of the
time of the so-called heliacal rising of the dog-star, Sirius, which
bore the Egyptian name Sothis. It chances that, as viewed from about
the region of Heliopolis, the sun at the time of the summer solstice
occupies an apparent position in the heavens close to the dog-star.
Now, as is well known, the Egyptians, seeing divinity back of almost
every phenomenon of nature, very naturally paid particular reverence
to so obviously influential a personage as the sun-god. In particular
they thought it fitting to do homage to him just as he was starting
out on his tour of Egypt in the morning; and that they might know
the precise moment of his coming, the Egyptian astronomer priests,
perched on the hill-tops near their temples, were wont to scan the
eastern horizon with reference to some star which had been observed
to precede the solar luminary. Of course the precession of the \textit{\emph{equinoxes}}\emph{,}
\textit{\emph{due}} to that axial wobble in which our clumsy earth
indulges, would change the apparent position of the fixed stars in
reference to the sun, so that the same star could not do service as
heliacal messenger indefinitely; but, on the other hand, these changes
are so slow that observations by many generations of astronomers would
be required to detect the shifting. It is believed by Lockyer, though
the evidence is not quite demonstrative, that the astronomical observations
of the Egyptians date back to a period when Sothis, the dog-star,
was not in close association with the sun on the morning of the summer
solstice. Yet, according to the calculations of Biot, the heliacal
rising of Sothis at the solstice was noted as early as the year 3285
B.C., and it is certain that this star continued throughout subsequent
centuries to keep this position of peculiar prestige. Hence it was
that Sothis came to be associated with Isis, one of the most important
divinities of Egypt, and that the day in which Sothis was first visible
in the morning sky marked the beginning of the new year; that day
coinciding, as already noted, with the summer solstice and with the
beginning of the Nile flow.

But now for the difficulties introduced by that unreckoned quarter
of a day. Obviously with a calendar of 365 days only, at the end of
four years, the calendar year, or vague year, as the Egyptians came
to call it, had gained by one full day upon the actual solar year---\ that
is to say, the heliacal rising of Sothis, the dog-\ star, would not
occur on new year's day of the faulty calendar, but a day later. And
with each succeeding period of four years the day of heliacal rising,
which marked the true beginning of the year---and which still, of
course, coincided with the inundation---would have fallen another
day behind the calendar. In the course of 120 years an entire month
would be lost; and in 480 years so great would become the shifting
that the seasons would be altogether misplaced; the actual time of
inundations corresponding with what the calendar registered as the
seed-time, and the actual seed-time in turn corresponding with the
harvest-time of the calendar.

At first thought this seems very awkward and confusing, but in all
probability the effects were by no means so much so in actual practice.
We need go no farther than to our own experience to know that the
names of seasons, as of months and days, come to have in the minds
of most of us a purely conventional significance. Few of us stop to
give a thought to the meaning of the words January, February, \textit{etc}.,
except as they connote certain climatic conditions. If, then, our
own calendar were so defective that in the course of 120 years the
month of February had shifted back to occupy the position of the original
January, the change would have been so gradual, covering the period
of two life-times or of four or five average generations, that it
might well escape general observation.

Each succeeding generation of Egyptians, then, may not improbably
have associated the names of the seasons with the contemporary climatic
conditions, troubling themselves little with the thought that in an
earlier age the climatic conditions for each period of the calendar
were quite different. We cannot well suppose, however, that the astronomer
priests were oblivious to the true state of things. Upon them devolved
the duty of predicting the time of the Nile flood; a duty they were
enabled to perform without difficulty through observation of the rising
of the solstitial sun and its Sothic messenger. To these observers
it must finally have been apparent that the shifting of the seasons
was at the rate of one day in four years; this known, it required
no great mathematical skill to compute that this shifting would finally
effect a complete circuit of the calendar, so that after (4$\times $365=)\ 1460
years the first day of the calendar year would again coincide with
the heliacal rising of Sothis and with the coming of the Nile flood.
In other words, 1461 vague years or Egyptian calendar years of 365
days each correspond to 1460 actual solar years of 365$\frac{1}{4}$
days each. This period, measured thus by the heliacal rising of Sothis,
is spoken of as the Sothic cycle.

To us who are trained from childhood to understand that the year consists
of (approximately)\ 365$\frac{1}{4}$ days, and to know that the
calendar may be regulated approximately by the introduction of an
extra day every fourth year, this recognition of the Sothic cycle
seems simple enough. Yet if the average man of us will reflect how
little he knows, of his own knowledge, of the exact length of the
year, it will soon become evident that the appreciation of the faults
of the calendar and the knowledge of its periodical adjustment constituted
a relatively high development of scientific knowledge on the part
of the Egyptian astronomer. It may be added that various efforts to
reform the calendar were made by the ancient Egyptians, but that they
cannot be credited with a satisfactory solution of the problem; for,
of course, the Alexandrian scientists of the Ptolemaic period (whose
work we shall have occasion to review presently)\ were not Egyptians
in any proper sense of the word, but Greeks.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc40}\end{center}

\noindent \begin{center}\noun{\small Twelve Stages in the Life of
the Sun and its Twelve Forms Throughout the Day}\end{center}{\small \par}

\noindent \emph{\footnotesize (From a drawing by Faucher-Gudin in
Maspero's} {\footnotesize Dawn of Civilization}\emph{\footnotesize ,
from the ceiling of the Hall of the New Year at Edfû.)}
\end{figure}
Since so much of the time of the astronomer priests was devoted to
observation of the heavenly bodies, it is not surprising that they
should have mapped out the apparent course of the moon and the visible
planets in their nightly tour of the heavens, and that they should
have divided the stars of the firmament into more or less arbitrary
groups or constellations. That they did so is evidenced by various
sculptured representations of constellations corresponding to signs
of the zodiac which still ornament the ceilings of various ancient
temples. Unfortunately the decorative sense, which was always predominant
with the Egyptian sculptor, led him to take various liberties with
the distribution of figures in these representations of the constellations,
so that the inferences drawn from them as to the exact map of the
heavens as the Egyptians conceived it cannot be fully relied upon.
It appears, however, that the Egyptian astronomer divided the zodiac
into twenty-four \emph{decani}, or constellations. The arbitrary groupings
of figures, with the aid of which these are delineated, bear a close
resemblance to the equally arbitrary outlines which we are still accustomed
to use for the same purpose.


\section*{\raggedright IDEAS OF COSMOLOGY}

\addcontentsline{toc}{section}{IDEAS OF COSMOLOGY}

In viewing this astronomical system of the Egyptians one cannot avoid
the question as to just what interpretation was placed upon it as
regards the actual mechanical structure of the universe. A proximal
answer to the question is supplied us with a good deal of clearness.
It appears that the Egyptian conceived the sky as a sort of tangible
or material roof placed above the world, and supported at each of
its four corners by a column or pillar, which was later on conceived
as a great mountain. The earth itself was conceived to be a rectangular
box, longer from north to south than from east to west; the upper
surface of this box, upon which man lived, being slightly concave
and having, of course, the valley of the Nile as its centre. The pillars
of support were situated at the points of the compass; the northern
one being located beyond the Mediterranean Sea; the southern one away
beyond the habitable regions towards the source of the Nile, and the
eastern and western ones in equally inaccessible regions. Circling
about the southern side of the world was a great river suspended in
mid-air on something comparable to mountain cliffs; on which river
the sun-god made his daily course in a boat, fighting day by day his
ever-recurring battle against Set, the demon of darkness. The wide
channel of this river enabled the sun-god to alter his course from
time to time, as he is observed to do; in winter directing his bark
towards the farther bank of the channel; in summer gliding close to
the nearer bank. As to the stars, they were similar lights, suspended
from the vault of the heaven; but just how their observed motion of
translation across the heavens was explained is not apparent. It is
more than probable that no one explanation was universally accepted.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc42}\end{center}

\noindent \begin{center}\noun{\small Shu Separating Sibû and Nuit}\end{center}{\small \par}

\noindent \emph{\footnotesize (From a drawing by Faucher-Gudin in
Maspero's} {\footnotesize Dawn of Civilization}\emph{\footnotesize ,
from a painting on a mummy-case in the Turin Museum. See p.42.)}
\end{figure}
In explaining the origin of this mechanism of the heavens, the Egyptian
imagination ran riot. Each separate part of Egypt had its own hierarchy
of gods, and more or less its own explanations of cosmogony. There
does not appear to have been any one central story of creation that
found universal acceptance, any more than there was one specific deity
everywhere recognized as supreme among the gods. Perhaps the most
interesting of the cosmogonic myths was that which conceived that
\textit{\emph{Nuit}}, the goddess of night, had been torn from the
arms of her husband, Sibu the earth-god, and elevated to the sky despite
her protests and her husband's struggles, there to remain supported
by her four limbs, which became metamorphosed into the pillars, or
mountains, already mentioned. The forcible elevation of \textit{\emph{Nuit}}
had been effected on the day of creation by a new god, Shu, who came
forth from the primeval waters. A painting on the mummy case of one
Betuhamon, now in the Turin Museum, illustrates, in the graphic manner
so characteristic of the Egyptians, this act of creation. As Maspero%
\footnote{G.\ Maspero, \textit{Histoire} \emph{Ancienne} \textit{des} \emph{Peuples
de l'Orient} \textit{Classique}, \textit{\emph{Paris}}, 1895. Translated
as (1)\ \emph{The Dawn of Civilization}, (2)\ \emph{The Struggle
of the Nations}, (3)\ \emph{The Passing of the Empires}, 3 \textit{\emph{vols}}.,
London and New York, 1894-1900. Professor Maspero is one of the most
famous of living Orientalists. His most important special studies
have to do with Egyptology, but his writings cover the entire field
of Oriental antiquity. He is a notable stylist, and his works are
at once readable and authoritative.%
} points out, the struggle of Sibu resulted in contorted attitudes
to which the irregularities of the earth's surface are to be ascribed.

In contemplating such a scheme of celestial mechanics as that just
outlined, one cannot avoid raising the question as to just the degree
of literalness which the Egyptians themselves put upon it. We know
how essentially eye-minded the Egyptian was, to use a modern psychological
phrase---that is to say, how essential to him it seemed that all his
conceptions should be visualized. The evidences of this are everywhere:
all his gods were made tangible; he believed in the immortality of
the soul, yet he could not conceive of such immortality except in
association with an immortal body; he must mummify the body of the
dead, else, as he firmly believed, the dissolution of the spirit would
take place along with the dissolution of the body itself. His world
was peopled everywhere with spirits, but they were spirits associated
always with corporeal bodies; his gods found lodgment in sun and moon
and stars; in earth and water; in the bodies of reptiles and birds
and mammals. He worshipped all of these things: the sun, the moon,
water, earth, the spirit of the Nile, the ibis, the cat, the ram,
and \textit{apis} the bull; but, so far as we can judge, his imagination
did not reach to the idea of an absolutely incorporeal deity. Similarly
his conception of the mechanism of the heavens must be a tangibly
mechanical one. He must think of the starry firmament as a substantial
entity which could not defy the law of gravitation, and which, therefore,
must have the same manner of support as is required by the roof of
a house or temple. We know that this idea of the materiality of the
firmament found elaborate expression in those later cosmological guesses
which were to dominate the thought of Europe until the time of Newton.
We need not doubt, therefore, that for the Egyptian this solid vault
of the heavens had a very real existence. If now and then some dreamer
conceived the great bodies of the firmament as floating in a less
material plenum---and such iconoclastic dreamers there are in all
ages---no record of his musings has come down to us, and we must freely
admit that if such thoughts existed they were alien to the character
of the Egyptian mind as a whole.

While the Egyptians conceived the heavenly bodies as the abiding-place
of various of their deities, it does not appear that they practised
astrology in the later acceptance of that word. This is the more remarkable
since the conception of lucky and unlucky days was carried by the
Egyptians to the extremes of absurdity. {}``One day was lucky or
unlucky,''\ says Erman,%
\footnote{Adolf Erman, \emph{Life in Ancient Egypt}, London, 1894, p. 352.\ (Translated
from the original German work entitled \emph{Aegypten} \textit{und}
\emph{Aegyptisches Leben in Alterthum}, Tilbigen, 1887.)\ An altogether
admirable work, full of interest for the general reader, though based
on the most erudite studies.%
} {}``according as a good or bad mythological incident took place
on that day. For instance, the 1st of Mechir, on which day the sky
was raised, and the 27th of Athyr, when Horus and Set concluded peace
together and divided the world between them, were lucky days; on the
other hand, the 14th of Tybi, on which Isis and Nephthys mourned for
Osiris, was an unlucky day. With the unlucky days, which, fortunately,
were less in number than the lucky days, they distinguished different
degrees of ill-luck. Some were very unlucky, others only threatened
ill-luck, and many, like the 17th and the 27th Choiakh, were partly
good and partly bad according to the time of day. Lucky days might,
as a rule, be disregarded. At most it might be as well to visit some
specially renowned temple, or to `celebrate a joyful day at home,'\ but
no particular precautions were really necessary; and, above all, it
was said, `what thou also seest on the day is lucky.' It was quite
otherwise with the unlucky and dangerous days, which imposed so many
and such great limitations on people that those who wished to be prudent
were always obliged to bear them in mind when determining on any course
of action. Certain conditions were easy to carry out. Music and singing
were to be avoided on the 14th Tybi, the day of the mourning of Osiris,
and no one was allowed to wash on the 16th Tybi; whilst the name of
Set might not be pronounced on the 24th of Pharmuthi. Fish was forbidden
on certain days; and what was still more difficult in a country so
rich in mice, on the 12th of Tybi no mouse might be seen. The most
tiresome prohibitions, however, were those which occurred not infrequently,
namely, those concerning work and going out: for instance, four times
in Paophi the people had to `do nothing at all,'\ and five times
to sit the whole day or half the day in the house; and the same rule
had to be observed each month. It was impossible to rejoice if a child
was born on the 23d of Thoth; the parents knew it could not live.
Those born on the 20th of Choiakh would become blind, and those born
on the 3d of Choiakh, deaf.''


\section*{\raggedright CHARMS AND INCANTATIONS}

\addcontentsline{toc}{section}{CHARMS AND INCANTATIONS}

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc46}\end{center}

\noindent \begin{center}\noun{\small The Self-Propelling Boat Containing
the Sun, under the Protection of the Two Eyes}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (Redrawn from Maspero's}
{\footnotesize Dawn of Civilization}\emph{\footnotesize .)}\end{center}
\end{figure}
Where such conceptions as these pertained, it goes without saying
that charms and incantations intended to break the spell of the unlucky
omens were equally prevalent. Such incantations consisted usually
of the recitation of certain phrases based originally, it would appear,
upon incidents in the history of the gods. The words which the god
had spoken in connection with some lucky incident would, it was thought,
prove effective now in bringing good luck to the human supplicant---that
is to say, the magician hoped through repeating the words of the god
to exercise the magic power of the god. It was even possible, with
the aid of the magical observances, partly to balk fate itself. Thus
the person predestined through birth on an unlucky day to die of a
serpent bite might postpone the time of this fateful visitation to
extreme old age. The like uncertainty attached to those spells which
one person was supposed to be able to exercise over another. It was
held, for example, that if something belonging to an individual, such
as a lock of hair or a paring of the nails, could be secured and incorporated
in a waxen figure, this figure would be intimately associated with
the personality of that individual. An enemy might thus secure occult
power over one; any indignity practised upon the waxen figure would
result in like injury to its human prototype. If the figure were bruised
or beaten, some accident would overtake its double; if the image were
placed over a fire, the human being would fall into a fever, and so
on. But, of course, such mysterious evils as these would be met and
combated by equally mysterious processes; and so it was that the entire
art of medicine was closely linked with magical practices. It was
not, indeed, held, according to Maspero, that the magical spells of
enemies were the sole sources of human ailments, but one could never
be sure to what extent such spells entered into the affliction; and
so closely were the human activities associated in the mind of the
Egyptian with one form or another of occult influences that purely
physical conditions were at a discount. In the later times, at any
rate, the physician was usually a priest, and there was a close association
between the material and spiritual phases of therapeutics. Erman%
\footnote{Erman, \emph{op.\ cit.}, \textit{\emph{pp}}.\ 356, 357.%
} tells us that the following formula had to be recited at the preparation
of all medicaments: {}``That Isis might make free, make free. That
Isis might make Horus free from all evil that his brother Set had
done to him when he slew his father, Osiris. O Isis, great enchantress,
free me, release me from all evil red things, from the fever of the
god, and the fever of the goddess, from death and death from pain,
and the pain which comes over me; as thou hast freed, as thou hast
released thy son Horus, whilst I enter into the fire and come forth
from the water,''\ \textit{etc}. Again, when the invalid took the
medicine, an incantation had to be said which began thus: {}``Come
remedy, come drive it out of my heart, out of these limbs strong in
magic power with the remedy.'' He adds: {}``There may have been
a few rationalists amongst the Egyptian doctors, for the number of
magic formul\ae{} varies much in the different books. The book that
we have specially taken for a foundation for this account of Egyptian
medicine---the great papyrus of the eighteenth dynasty edited by \textit{\emph{Ebers}}%
\footnote{Erman, \emph{op.\ cit}., p.\ 357. The work on Egyptian medicine
here referred to is \textit{\emph{Georg}} \emph{}\textit{\emph{Ebers}}\emph{'}\ edition
of an Egyptian document discovered by the explorer whose name it bears.
It remains the most important source of our knowledge of Egyptian
medicine. As mentioned in the text, this document dates from the eighteenth
dynasty---that is to say, from about the fifteenth or sixteenth century,
B.C., a relatively late period of Egyptian history.%
}---contains, for instance, far fewer exorcisms than some later writings
with similar contents, probably because the doctor who compiled this
book of recipes from older sources had very little liking for magic.''

It must be understood, however---indeed, what has just been said implies
as much---that the physician by no means relied upon incantations
alone; on the contrary, he equipped himself with an astonishing variety
of medicaments. He had a particular fondness for what the modern physician
speaks of as a {}``shot-gun'' prescription---one containing a great
variety of ingredients. Not only did herbs of many kinds enter into
this, but such substances as lizard's blood, the teeth of swine, putrid
meat, the moisture from pigs'\ ears, boiled horn, and numerous other
even more repellent ingredients. Whoever is familiar with the formul\ae{}
employed by European physicians even so recently as the eighteenth
century will note a striking similarity here. Erman points out that
the modern Egyptian even of this day holds closely to many of the
practices of his remote ancestor. In particular, the efficacy of the
beetle as a medicinal agent has stood the test of ages of practice.
{}``Against all kinds of witchcraft,''\ says an ancient formula,
{}``a great scarabae{}us beetle; cut off his head and wings, boil
him; put him in oil and lay him out; then cook his head and wings,
put them in snake fat, boil, and let the patient drink the mixture.''
The modern Egyptian, says Erman, uses almost precisely the same recipe,
except that the snake fat is replaced by modern oil.

In evidence of the importance which was attached to practical medicine
in the Egypt of an early day, the names of several physicians have
come down to us from an age which has preserved very few names indeed,
save those of kings. In reference to this Erman says:%
\footnote{Erman, \emph{op.\ cit.}, p.\ 357.%
} {}``We still know the names of some of the early body physicians
of this time; Sechmetna'eonch, `chief physician of the Pharaoh,'\ and
Nesmenan his chief, the `superintendent of the physicians of the Pharaoh.'
The priests also of the lioness-headed goddess Sechmet seem to have
been famed for their medical wisdom, whilst the son of this goddess,
the demi-god Imhotep, was in later times considered to be the creator
of medical knowledge. These ancient doctors of the New Empire do not
seem to have improved upon the older conceptions about the construction
of the human body.''

As to the actual scientific attainments of the Egyptian physician,
it is difficult to speak with precision. Despite the cumbersome formul\ae{}
and the grotesque incantations, we need not doubt that a certain practical
value attended his therapeutics. He practised almost pure empiricism,
however, and certainly it must have been almost impossible to determine
which ones, if any, of the numerous ingredients of the prescription
had real efficacy.

The practical anatomical knowledge of the physician, there is every
reason to believe, was extremely limited. At first thought it might
seem that the practice of embalming would have led to the custom of
dissecting human bodies, and that the Egyptians, as a result of this,
would have excelled in the knowledge of anatomy. But the actual results
were rather the reverse of this. Embalming the dead, it must be recalled,
was a purely religious observance. It took place under the superintendence
of the priests, but so great was the reverence for the human body
that the priests themselves were not permitted to make the abdominal
incision which was a necessary preliminary of the process. This incision,
as we are informed by both Herodotus%
\footnote{The \emph{History} of Herodotus, \textit{\emph{pp}}.\ 85-90. There
are numerous translations of the famous work of the {}``father of
history,''\ one of the most recent and authoritative being that
of G.\ C.\ Macaulay, M.A., in two volumes, Macmillan \&\ Co., London
and New York, 1890.%
} and Diodorus,%
\footnote{The \emph{Historical Library} of Diodorus the Sicilian, London, 1700.
This most famous of ancient world histories is difficult to obtain
in an English version. The most recently published translation known
to the writer is that of G.\ Booth, London, 1814.%
} was made by a special officer, whose status, if we may believe the
explicit statement of Diodorus, was quite comparable to that of the
modern hangman. The \emph{paraschistas}, as he was called, having
performed his necessary but obnoxious function, with the aid of a
sharp Ethiopian stone, retired hastily, leaving the remaining processes
to the priests. These, however, confined their observations to the
abdominal viscera; under no consideration did they make other incisions
in the body. It follows, therefore, that their opportunity for anatomical
observations was most limited.

Since even the necessary mutilation inflicted on the corpse was regarded
with such horror, it follows that anything in the way of dissection
for a less sacred purpose was absolutely prohibited. Probably the
same prohibition extended to a large number of animals, since most
of these were held sacred in one part of Egypt or another. Moreover,
there is nothing in what we know of the Egyptian mind to suggest the
probability that any Egyptian physician would make extensive anatomical
observations for the love of pure knowledge. All Egyptian science
is eminently practical. If we think of the Egyptian as mysterious,
it is because of the superstitious observances that we everywhere
associate with his daily acts; but these, as we have already tried
to make clear, were really based on scientific observations of a kind,
and the attempt at true inferences from these observations. But whether
or not the Egyptian physician desired anatomical knowledge, the results
of his inquiries were certainly most meagre. The essentials of his
system had to do with a series of vessels, alleged to be twenty-two
or twenty-four in number, which penetrated the head and were distributed
in pairs to the various members of the body, and which were vaguely
thought of as carriers of water, air, excretory fluids, \textit{etc}.
Yet back of this vagueness, as must not be overlooked, there was an
all-essential recognition of the heart as the central vascular organ.
The heart is called the beginning of all the members. Its vessels,
we are told, {}``lead to all the members; whether the doctor lays
his finger on the forehead, on the back of the head, on the hands,
on the place of the stomach (?), on the arms, or on the feet, everywhere
he meets with the heart, because its vessels lead to all the members.''%
\footnote{Erman, \emph{op.\ cit}., p.\ 357.%
} This recognition of the pulse must be credited to the Egyptian physician
as a piece of practical knowledge, in some measure off-setting the
vagueness of his anatomical theories.


\section*{\raggedright ABSTRACT SCIENCE}

\addcontentsline{toc}{section}{ABSTRACT SCIENCE}

But, indeed, practical knowledge was, as has been said over and over,
the essential characteristic of Egyptian science. Yet another illustration
of this is furnished us if we turn to the more abstract departments
of thought and inquire what were the Egyptian attempts in such a field
as mathematics. The answer does not tend greatly to increase our admiration
for the Egyptian mind. We are led to see, indeed, that the Egyptian
merchant was able to perform all the computations necessary to his
craft, but we are forced to conclude that the knowledge of numbers
scarcely extended beyond this, and that even here the methods of reckoning
were tedious and cumbersome. Our knowledge of the subject rests largely
upon the so-called \emph{Papyrus Rhind},%
\footnote{The \emph{Papyrus Rhind} is a sort of mathematical hand-book of the
ancient Egyptians; it was made in the time of the Hyksos Kings (about
2000 B.C.), but is a copy of an older book. It is now preserved in
the British Museum.%
} which is a sort of mythological hand-book of the ancient Egyptians.
Analyzing this document, Professor Erman concludes that the knowledge
of the Egyptians was adequate to all practical requirements. Their
mathematics taught them {}``how in the exchange of bread for beer
the respective value was to be determined when converted into a quantity
of corn; how to reckon the size of a field; how to determine how a
given quantity of corn would go into a granary of a certain size,''\ and
like every-day problems. Yet they were obliged to make some of their
simple computations in a very roundabout way. It would appear, for
example, that their mental arithmetic did not enable them to multiply
by a number larger than two, and that they did not reach a clear conception
of complex fractional numbers. They did, indeed, recognize that each
part of an object divided into 10 pieces became $\frac{1}{10}$ of
that object; they even grasped the idea of $\frac{2}{3}$, this being
a conception easily visualized; but they apparently did not visualize
such a conception as $\frac{3}{10}$ except in the crude form of $\frac{1}{10}$
plus $\frac{1}{10}$ plus $\frac{1}{10}$. Their entire idea of division
seems defective. They viewed the subject from the more elementary
stand-point of multiplication. Thus, in order to find out how many
times 7 is contained in 77, an existing example shows that the numbers
representing 1 times 7, 2 times 7, 4 times 7, 8 times 7 were set down
successively and various experimental additions made to find out which
sets of these numbers aggregated 77.

\noindent \begin{center}\begin{tabular}{|c|c|}
\hline 
---1&
7\\
\hline 
---2&
14\\
\hline 
4&
28\\
\hline 
---8&
56\\
\hline
\end{tabular}\end{center}

\noindent A line before the first, second, and fourth of these numbers
indicated that it is necessary to multiply 7 by 1 plus 2 plus 8---that
is, by 11, in order to obtain 77; that is to say, 7 goes 11 times
in 77. All this seems very cumbersome indeed, yet we must not overlook
the fact that the process which goes on in our own minds in performing
such a problem as this is precisely similar, except that we have learned
to slur over certain of the intermediate steps with the aid of a memorized
multiplication table. In the last analysis, division is only the obverse
side of multiplication, and any one who has not learned his multiplication
table is reduced to some such expedient as that of the Egyptian. Indeed,
whenever we pass beyond the range of our memorized multiplication
table---which for most of us ends with the twelves---the experimental
character of the trial multiplication through which division is finally
effected does not so greatly differ from the experimental efforts
which the Egyptian was obliged to apply to smaller numbers.

Despite his defective comprehension of fractions, the Egyptian was
able to work out problems of relative complexity; for example, he
could determine the answer of such a problem as this: a number together
with its fifth part makes 21; what is the number? The process by which
the Egyptian solved this problem seems very cumbersome to any one
for whom a rudimentary knowledge of algebra makes it simple, yet the
method which we employ differs only in that we are enabled, thanks
to our hypothetical $x$, to make a short cut, and the essential fact
must not be overlooked that the Egyptian reached a correct solution
of the problem. With all due desire to give credit, however, the fact
remains that the Egyptian was but a crude mathematician. Here, as
elsewhere, it is impossible to admire him for any high development
of theoretical science. First, last, and all the time, he was practical,
and there is nothing to show that the thought of science for its own
sake, for the mere love of knowing, ever entered his head.

In general, then, we must admit that the Egyptian had not progressed
far in the hard way of abstract thinking. He worshipped everything
about him because he feared the result of failing to do so. He embalmed
the dead lest the spirit of the neglected one might come to torment
him. Eye-minded as he was, he came to have an artistic sense, to love
decorative effects. But he let these always take precedence over his
sense of truth; as, for example, when he modified his lists of kings
at Abydos to fit the space which the architect had left to be filled;
he had no historical sense to show to him that truth should take precedence
over mere decoration. And everywhere he lived in the same happy-go-lucky
way. He loved personal ease, the pleasures of the table, the luxuries
of life, games, recreations, festivals. He took no heed for the morrow,
except as the morrow might minister to his personal needs. Essentially
a sensual being, he scarcely conceived the meaning of the intellectual
life in the modern sense of the term. He had perforce learned some
things about astronomy, because these were necessary to his worship
of the gods; about practical medicine, because this ministered to
his material needs; about practical arithmetic, because this aided
him in every-day affairs. The bare rudiments of an historical science
may be said to be crudely outlined in his defective lists of kings.
But beyond this he did not go. Science as science, and for its own
sake, was unknown to him. He had gods for all material functions,
and festivals in honor of every god; but there was no goddess of mere
wisdom in his pantheon. The conception of Minerva was reserved for
the creative genius of another people.


\chapter*{\raggedright III. SCIENCE OF BABYLONIA AND ASSYRIA}

\addcontentsline{toc}{chapter}{III. SCIENCE OF BABYLONIA\\
AND ASSYRIA}

\markboth{A HISTORY OF SCIENCE, BOOK I}{III. BABYLONIA AND ASSYRIA}

Throughout classical antiquity Egyptian science was famous. We know
that Plato spent some years in Egypt in the hope of penetrating the
alleged mysteries of its fabled learning; and the story of the Egyptian
priest who patronizingly assured Solon that the Greeks were but babes
was quoted everywhere without disapproval. Even so late as the time
of Augustus, we find Diodorus, the Sicilian, looking back with veneration
upon the Oriental learning, to which Pliny also refers with unbounded
respect. From what we have seen of Egyptian science, all this furnishes
us with a somewhat striking commentary upon the attainments of the
Greeks and Romans themselves. To refer at length to this would be
to anticipate our purpose; what now concerns us is to recall that
all along there was another nation, or group of nations, that disputed
the palm for scientific attainments. This group of nations found a
home in the valley of the Tigris and Euphrates. Their land was named
Mesopotamia by the Greeks, because a large part of it lay between
the two rivers just mentioned. The peoples themselves are familiar
to every one as the Babylonians and the Assyrians. These peoples were
of Semitic stock---allied, therefore, to the ancient Hebrews and Ph\oe{}nicians
and of the same racial stem with the Arameans and Arabs.

The great capital of the Babylonians during the later period of their
history was the famed city of Babylon itself; the most famous capital
of the Assyrians was Nineveh, that city to which, as every Bible-student
will recall, the prophet Jonah was journeying when he had a much-exploited
experience, the record of which forms no part of scientific annals.
It was the kings of Assyria, issuing from their palaces in Nineveh,
who dominated the civilization of Western Asia during the heyday of
Hebrew history, and whose deeds are so frequently mentioned in the
Hebrew chronicles. Later on, in the year 606 B.C., Nineveh was overthrown
by the \textit{\emph{Medes%
\footnote{The \textit{\emph{Medes}}. Some difference of opinion exists among
historians as to the exact ethnic relations of the conquerors; the
precise date of the fall of Nineveh is also in doubt.%
}}} and Babylonians. The famous city was completely destroyed, never
to be rebuilt. Babylon, however, though conquered subsequently by
Cyrus and held in subjection by Darius,%
\footnote{Darius. The familiar Hebrew narrative ascribes the first Persian conquest
of Babylon to Darius, but inscriptions of Cyrus and of Nabonidus,
the Babylonian king, make it certain that Cyrus was the real conqueror.
These inscriptions are preserved on cylinders of baked clay, of the
type made familiar by the excavation of the past fifty years, and
they are invaluable historical documents.%
} the Persian kings, continued to hold sway as a great world-capital
for some centuries. The last great historical event that occurred
within its walls was the death of Alexander the Great, which took
place there in the year 322 B.C.

In the time of Herodotus the fame of Babylon was at its height, and
the father of history has left us a most entertaining account of what
he saw when he visited the wonderful capital. Unfortunately, Herodotus
was not a scholar in the proper acceptance of the term. He probably
had no inkling of the Babylonian language, so the voluminous records
of its literature were entirely shut off from his observation. He
therefore enlightens us but little regarding the science of the Babylonians,
though his observations on their practical civilization give us incidental
references of no small importance. Somewhat more detailed references
to the scientific attainments of the Babylonians are found in the
fragments that have come down to us of the writings of the great Babylonian
historian, Berosus,%
\footnote{Berosus. The fragments of Berosus have been translated by L.\ P.\ Cory,
and included in his \emph{Ancient Fragments of Phenician, Chaldean,
Egyptian, and Other Writers}, London, 1826, second edition, 1832.%
} who was born in Babylon about 330 B.C., and who was, therefore, a
contemporary of Alexander the Great. But the writings of Berosus also,
or at least such parts of them as have come down to us, leave very
much to be desired in point of explicitness. They give some glimpses
of Babylonian history, and they detail at some length the strange
mythical tales of creation that entered into the Babylonian conception
of cosmogony---details which find their counterpart in the allied
recitals of the Hebrews. But taken all in all, the glimpses of the
actual state of Chaldean%
\footnote{Chaldean learning. Recent writers reserve the name Chaldean for the
later period of Babylonian history---the time when the Greeks came
in contact with the Mesopotamians---in contradistinction to the earlier
periods which are revealed to us by the archae{}ological records.%
} learning, as it was commonly called, amounted to scarcely more than
vague wonder-tales. No one really knew just what interpretation to
put upon these tales until the explorers of the nineteenth century
had excavated the ruins of the Babylonian and Assyrian cities, bringing
to light the relics of their wonderful civilization. But these relics
fortunately included vast numbers of written documents, inscribed
on tablets, prisms, and cylinders of \textit{terra}-\emph{cotta}.
When nineteenth-century scholarship had penetrated the mysteries of
the strange script, and ferreted out the secrets of an unknown tongue,
the world at last was in possession of authentic records by which
the traditions regarding the Babylonians and Assyrians could be tested.
Thanks to these materials, a new science commonly spoken of as Assyriology
came into being, and a most important chapter of human history was
brought to light. It became apparent that the Greek ideas concerning
Mesopotamia, though vague in the extreme, were founded on fact. No
one any longer questions that the Mesopotamian civilization was fully
on a par with that of Egypt; indeed, it is rather held that superiority
lay with the Asiatics. Certainly, in point of purely scientific attainments,
the Babylonians passed somewhat beyond their Egyptian competitors.
All the evidence seems to suggest also that the Babylonian civilization
was even more ancient than that of Egypt. The precise dates are here
in dispute; nor for our present purpose need they greatly concern
us. But the Assyrio-Babylonian records have much greater historical
accuracy as regards matters of chronology than have the Egyptian,
and it is believed that our knowledge of the early Babylonian history
is carried back, with some certainty, to King Sargon of Agade,%
\footnote{King Sargon of Agade. The date given for this early king must not
be accepted as absolute; but it is probably approximately correct.%
} for whom the date 3800 B.C.\ is generally accepted; while somewhat
vaguer records give us glimpses of periods as remote as the sixth,
perhaps even the seventh or eighth millenniums before our era.

At a very early period Babylon itself was not a capital and Nineveh
had not come into existence. The important cities, such as Nippur
and Shirpurla, were situated farther to the south. It is on the site
of these cities that the recent excavations have been made, such as
those of the University of Pennsylvania expeditions at Nippur,%
\footnote{Nippur. See the account of the early expeditions as recorded by the
director, Dr.\ John P.\ Peters, \emph{Nippur, or Explorations and
Adventures}, \textit{etc}., New York and London, 1897.%
} which are giving us glimpses into remoter recesses of the historical
period.

Even if we disregard the more problematical early dates, we are still
concerned with the records of a civilization extending unbroken throughout
a period of about four thousand years; the actual period is in all
probability twice or thrice that. Naturally enough, the current of
history is not an unbroken stream throughout this long epoch. It appears
that at least two utterly different ethnic elements are involved.
A preponderance of evidence seems to show that the earliest civilized
inhabitants of Mesopotamia were not Semitic, but an alien race, which
is now commonly spoken of as Sumerian. This people, of whom we catch
glimpses chiefly through the records of its successors, appears to
have been subjugated or overthrown by Semitic invaders, who, coming
perhaps from Arabia (their origin is in dispute), took possession
of the region of the Tigris and Euphrates, learned from the Sumerians
many of the useful arts, and, partly perhaps because of their mixed
lineage, were enabled to develop the most wonderful civilization of
antiquity. Could we analyze the details of this civilization from
its earliest to its latest period we should of course find the same
changes which always attend racial progress and decay. We should then
be able, no doubt, to speak of certain golden epochs and their periods
of decline. To a certain meagre extent we are able to do this now.
We know, for example, that King Khammurabi, who lived about 2200 B.C.,
was a great law-giver, the ancient prototype of Justinian; and the
epochs of such Assyrian kings as Sargon \textit{\emph{II.}}, Asshurnazirpal,
Sennacherib, and Asshurbanapal stand out with much distinctness. Yet,
as a whole, the record does not enable us to trace with clearness
the progress of scientific thought. At best we can gain fewer glimpses
in this direction than in almost any other, for it is the record of
war and conquest rather than of the peaceful arts that commanded the
attention of the ancient scribe. So in dealing with the scientific
achievements of these peoples, we shall perforce consider their varied
civilizations as a unity, and attempt, as best we may, to summarize
their achievements as a whole. For the most part, we shall not attempt
to discriminate as to what share in the final product was due to Sumerian,
what to Babylonian, and what to Assyrian. We shall speak of Babylonian
science as including all these elements; and drawing our information
chiefly from the relatively late Assyrian and Babylonian sources,
which, therefore, represent the culminating achievements of all these
ages of effort, we shall attempt to discover what was the actual status
of Mesopotamian science at its climax. In so far as we succeed, we
shall be able to judge what scientific heritage Europe received from
the Orient; for in the records of Babylonian science we have to do
with the Eastern mind at its best. Let us turn to the specific inquiry
as to the achievements of the Chaldean scientist whose fame so dazzled
the eyes of his contemporaries of the classic world.


\section*{\raggedright BABYLONIAN ASTRONOMY}

\addcontentsline{toc}{section}{BABYLONIAN ASTRONOMY}

Our first concern naturally is astronomy, this being here, as in Egypt,
the first-born and the most important of the sciences. The fame of
the Chaldean astronomer was indeed what chiefly commanded the admiration
of the Greeks, and it was through the results of astronomical observations
that Babylonia transmitted her most important influences to the Western
world. {}``Our division of time is of Babylonian origin,''\ says
Hommel;%
\footnote{Fritz Hommel, \textit{Geschichte} \emph{Babyloniens} \textit{und}
\emph{Assyriens}, Berlin, 1885.%
} {}``to Babylonia we owe the week of seven days, with the names of
the planets for the days of the week, and the division into hours
and months.'' Hence the almost personal interest which we of to-day
must needs feel in the efforts of the Babylonian star-gazer.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc62}\end{center}

\noindent \begin{center}\noun{\small The World as Conceived by the
Chaldeans}\end{center}{\small \par}

\noindent \emph{\footnotesize (From a drawing by Faucher-Gudin in
Maspero's} {\footnotesize Dawn of Civilization}\emph{\footnotesize .)}
\end{figure}
It must not be supposed, however, that the Chaldean astronomer had
made any very extraordinary advances upon the knowledge of the Egyptian
{}``watchers of the night.'' After all, it required patient observation
rather than any peculiar genius in the observer to note in the course
of time such broad astronomical conditions as the regularity of the
moon's phases, and the relation of the lunar periods to the longer
periodical oscillations of the sun. Nor could the curious wanderings
of the planets escape the attention of even a moderately keen observer.
The chief distinction between the Chaldean and Egyptian astronomers
appears to have consisted in the relative importance they attached
to various of the phenomena which they both observed. The Egyptian,
as we have seen, centred his attention upon the sun. That luminary
was the abode of one of his most important gods. His worship was essentially
solar. The Babylonian, on the other hand, appears to have been peculiarly
impressed with the importance of the moon. He could not, of course,
overlook the attention-compelling fact of the solar year; but his
unit of time was the lunar period of thirty days, and his year consisted
of twelve lunar periods, or 360 days. He was perfectly aware, however,
that this period did not coincide with the actual year; but the relative
unimportance which he ascribed to the solar year is evidenced by the
fact that he interpolated an added month to adjust the calendar only
once in six years. Indeed, it would appear that the Babylonians and
Assyrians did not adopt precisely the same method of adjusting the
calendar, since the Babylonians had two intercular months called \textit{\emph{Elul}}
and Adar, whereas the Assyrians had only a single such month, called
the second Adar.%
\footnote{R.\ Campbell Thompson, \emph{Reports of the Magicians and Astrologers
of Nineveh and Babylon, London}, 1900, p.\ xix.%
} (The Ve'Adar of the Hebrews.)\ This diversity further emphasizes
the fact that it was the lunar period which received chief attention,
the adjustment of this period with the solar seasons being a necessary
expedient of secondary importance. It is held that these lunar periods
have often been made to do service for years in the Babylonian computations
and in the allied computations of the early Hebrews. The lives of
the Hebrew patriarchs, for example, as recorded in the Bible, are
perhaps reckoned in lunar {}``years.'' Divided by twelve, the {}``years''
of Methuselah accord fairly with the usual experience of mankind.

Yet, on the other hand, the convenience of the solar year in computing
long periods of time was not unrecognized, since this period is utilized
in reckoning the reigns of the Assyrian kings. It may be added that
the reign of a king {}``was not reckoned from the day of his accession,
but from the Assyrian new year's day, either before or after the day
of accession. There does not appear to have been any fixed rule as
to which new year's day should be chosen; but from the number of known
cases, it appears to have been the general practice to count the reigning
years from the new year's day nearest the accession, and to call the
period between the accession day and the first new year's day `the
beginning of the reign,'\ when the year from the new year's day was
called the first year, and the following ones were brought successively
from it. Notwithstanding, in the dates of several Assyrian and Babylonian
sovereigns there are cases of the year of accession being considered
as the first year, thus giving two reckonings for the reigns of various
monarchs, among others, Shalmaneser, Sennacherib, Nebuchadrezzar.''%
\footnote{George Smith, \emph{The Assyrian Canon}, p.\ 21.%
} This uncertainty as to the years of reckoning again emphasizes the
fact that the solar year did not have for the Assyrian chronology
quite the same significance that it has for us.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc64}\end{center}

\noindent \begin{center}\noun{\small Chaldean Map of the World}\end{center}{\small \par}

\noindent \emph{\footnotesize (From a drawing by Faucher-Gudin in
Maspero's} {\footnotesize Dawn of Civilization}\emph{\footnotesize .) }
\end{figure}
The Assyrian month commenced on the evening when the new moon was
first observed, or, in case the moon was not visible, the new month
started thirty days after the last month. Since the actual lunar period
is about twenty-nine and one-half days, a practical adjustment was
required between the months themselves, and this was probably effected
by counting alternate months as Only 29 days in length. Mr.\ R.\ Campbell
Thompson%
\footnote{Thompson, \emph{op.\ cit.}, p.\ xix.%
} is led by his studies of the astrological tablets to emphasize this
fact. He believes that {}``the object of the astrological reports
which related to the appearance of the moon and sun was to help determine
and foretell the length of the lunar month.'' Mr. Thompson believes
also that there is evidence to show that the interculary month was
added at a period less than six years. In point of fact, it does not
appear to be quite clearly established as to precisely how the adjustment
of days with the lunar months, and lunar months with the solar year,
was effected. It is clear, however, according to Smith, {}``that
the first 28 days of every month were divided into four weeks of seven
days each; the seventh, fourteenth, twenty-first, twenty-eighth days
respectively being Sabbaths, and that there was a general prohibition
of work on these days.'' Here, of course, is the foundation of the
Hebrew system of Sabbatical days which we have inherited. The sacredness
of the number seven itself---the belief in which has not been quite
shaken off even to this day---was deduced by the Assyrian astronomer
from his observation of the seven planetary bodies---namely, Sin (the
moon), Samas (the sun), Umunpawddu (Jupiter), Dilbat (Venus), Kaimanu
(Saturn), Gudud (Mercury), Mustabarru-mutanu (Mars).%
\footnote{Thompson, \emph{op.\ cit.}, p.\ 2.%
} Twelve lunar periods, making up approximately the solar year, gave
peculiar importance to the number twelve also. Thus the zodiac was
divided into twelve signs which astronomers of all subsequent times
have continued to recognize; and the duodecimal system of counting
took precedence with the Babylonian mathematicians over the more primitive
and, as it seems to us, more satisfactory decimal system.

Another discrepancy between the Babylonian and Egyptian years appears
in the fact that the Babylonian new year dates from about the period
of the vernal equinox and not from the solstice. Lockyer associates
this with the fact that the periodical inundation of the Tigris and
Euphrates occurs about the equinoctial period, whereas, as we have
seen, the Nile flood comes at the time of the solstice. It is but
natural that so important a phenomenon as the Nile flood should make
a strong impression upon the minds of a people living in a valley.
The fact that occasional excessive inundations have led to most disastrous
results is evidenced in the incorporation of stories of the almost
total destruction of mankind by such floods among the myth tales of
all peoples who reside in valley countries. The flooding of the Tigris
and Euphrates had not, it is true, quite the same significance for
the Mesopotamians that the Nile flood had for the Egyptians. Nevertheless
it was a most important phenomenon, and may very readily be imagined
to have been the most tangible index to the seasons. But in recognizing
the time of the inundations and the vernal equinox, the Assyrians
did not dethrone the moon from its accustomed precedence, for the
year was reckoned as commencing not precisely at the vernal equinox,
but at the new moon next before the equinox.


\section*{\raggedright ASTROLOGY}

\addcontentsline{toc}{section}{ASTROLOGY}

Beyond marking the seasons, the chief interests that actuated the
Babylonian astronomer in his observations were astrological. After
quoting Diodorus to the effect that the Babylonian priests observed
the position of certain stars in order to cast horoscopes, Thompson
tells us that from a very early day the very name Chaldean became
synonymous with magician. He adds that {}``from Mesopotamia, by way
of Greece and Rome, a certain amount of Babylonian astrology made
its way among the nations of the west, and it is quite probable that
many superstitions which we commonly record as the peculiar product
of western civilization took their origin from those of the early
dwellers on the alluvial lands of Mesopotamia. One Assurbanipal, king
of Assyria B.C.\ 668-626, added to the royal library at Nineveh his
contribution of tablets, which included many series of documents which
related exclusively to the astrology of the ancient Babylonians, who
in turn had borrowed it with modifications from the Sumerian invaders
of the country. Among these must be mentioned the series which was
commonly called `the Day of Bel,' and which was decreed by the learned
to have been written in the time of the great Sargon I., king of Agade,
3800 B.C. With such ancient works as these to guide them, the profession
of deducing omens from daily events reached such a pitch of importance
in the last Assyrian Empire that a system of making periodical reports
came into being. By these the king was informed of all the occurrences
in the heavens and on earth, and the results of astrological studies
in respect to after events. The heads of the astrological profession
were men of high rank and position, and their office was hereditary.
The variety of information contained in these reports is best gathered
from the fact that they were sent from cities as far removed from
each other as Assur in the north and Erech in the south, and it can
only be assumed that they were despatched by runners, or men mounted
on swift horses. As reports also came from Dilbat, Kutba, Nippur,
and Bursippa, all cities of ancient foundation, the king was probably
well acquainted with the general course of events in his empire.''%
\footnote{Thompson, \emph{op.\ cit.}, p.\ xvi.%
}

From certain passages in the astrological tablets, Thompson draws
the interesting conclusion that the Chaldean astronomers were acquainted
with some kind of a machine for reckoning time. He finds in one of
the tablets a phrase which he interprets to mean measure-governor,
and he infers from this the existence of a kind of a calculator. He
calls attention also to the fact that \textit{\emph{Sextus}} \emph{}\textit{\emph{Empiricus%
\footnote{\textit{\emph{Sextus}} \emph{}\textit{\emph{Empiricus}}, author of
\textit{Adversus} \emph{Mathematicos}, lived about 200 A.D.%
}}} states that the clepsydra was known to the Chaldeans, and that
Herodotus asserts that the Greeks borrowed certain measures of time
from the Babylonians. He finds further corroboration in the fact that
the Babylonians had a time-measure by which they divided the day and
the night; a measure called kasbu, which contained two hours. In a
report relating to the day of the vernal equinox, it is stated that
there are six kasbu of the day and six kasbu of the night.

While the astrologers deduced their omens from all the celestial bodies
known to them, they chiefly gave attention to the moon, noting with
great care the shape of its horns, and deducing such a conclusion
as that {}``if the horns are pointed the king will overcome whatever
he goreth,''\ and that {}``when the moon is low at its appearance,
the submission (of the people)\ of a far country will come.''%
\footnote{R.\ Campbell Thompson, \emph{op.\ cit.}, p.\ xxiv.%
} The relations of the moon and sun were a source of constant observation,
it being noted whether the sun and moon were seen together above the
horizon; whether one set as the other rose, and the like. And whatever
the phenomena, there was always, of course, a direct association between
such phenomena and the well-being of human kind---in particular the
king, at whose instance, and doubtless at whose expense, the observations
were carried out.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc68}\end{center}

\noindent \begin{center}\noun{\small Assyrian Baked Clay Prisms,
with Inscriptions of Kings Sennacherib (750-681 B.C.), Esarhaddon
(681-668 B.C.), and Ashur-Bani-Pal (668-626 B.C.)}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (Now in the British Museum.) }\end{center}
\end{figure}
From omens associated with the heavenly bodies it is but a step to
omens based upon other phenomena of nature, and we shall see in a
moment that the Babylonian prophets made free use of their opportunities
in this direction also. But before we turn from the field of astronomy,
it will be well to inform ourselves as to what system the Chaldean
astronomer had invented in explanation of the mechanics of the universe.
Our answer to this inquiry is not quite as definite as could be desired,
the vagueness of the records, no doubt, coinciding with the like vagueness
in the minds of the Chaldeans themselves. So far as we can interpret
the somewhat mystical references that have come down to us, however,
the Babylonian cosmology would seem to have represented the earth
as a circular plane surrounded by a great circular river, beyond which
rose an impregnable barrier of mountains, and resting upon an infinite
sea of waters. The material vault of the heavens was supposed to find
support upon the outlying circle of mountains. But the precise mechanism
through which the observed revolution of the heavenly bodies was effected
remains here, as with the Egyptian cosmology, somewhat conjectural.
The simple fact would appear to be that, for the Chaldeans as for
the Egyptians, despite their most careful observations of the tangible
phenomena of the heavens, no really satisfactory mechanical conception
of the cosmos was attainable. We shall see in due course by what faltering
steps the European imagination advanced from the crude ideas of Egypt
and Babylonia to the relatively clear vision of Newton and Laplace.


\section*{\raggedright CHALDEAN MAGIC}

\addcontentsline{toc}{section}{CHALDEAN MAGIC}

We turn now from the field of the astrologer to the closely allied
province of Chaldean magic---a province which includes the other;
which, indeed, is so all-encompassing as scarcely to leave any phase
of Babylonian thought outside its bounds.

The tablets having to do with omens, exorcisms, and the like magic
practices make up an astonishingly large proportion of the Babylonian
records. In viewing them it is hard to avoid the conclusion that the
superstitions which they evidenced absolutely dominated the life of
the Babylonians of every degree. Yet it must not be forgotten that
the greatest inconsistencies everywhere exist between the superstitious
beliefs of a people and the practical observances of that people.
No other problem is so difficult for the historian as that which confronts
him when he endeavors to penetrate the mysteries of an alien religion;
and when, as in the present case, the superstitions involved have
been transmitted from generation to generation, their exact practical
phases as interpreted by any particular generation must be somewhat
problematical. The tablets upon which our knowledge of these omens
is based are many of them from the libraries of the later kings of
Nineveh; but the omens themselves are, in such cases, inscribed in
the original Accadian form in which they have come down from remote
ages, accompanied by an Assyrian translation. Thus the superstitions
involved had back of them hundreds of years, even thousands of years,
of precedent; and we need not doubt that the ideas with which they
are associated were interwoven with almost every thought and deed
of the life of the people. Professor Sayce assures us that the Assyrians
and Babylonians counted no fewer than three hundred spirits of heaven,
and six hundred spirits of earth. {}``Like the Jews of the Talmud,''\ he
says, {}``they believed that the world was swarming with noxious
spirits, who produced the various diseases to which man is liable,
and might be swallowed with the food and drink which support life.''
Fox Talbot was inclined to believe that exorcisms were the exclusive
means used to drive away the tormenting spirits. This seems unlikely,
considering the uniform association of drugs with the magical practices
among their people. Yet there is certainly a strange silence of the
tablets in regard to medicine. Talbot tells us that sometimes divine
images were brought into the sick-chamber, and written texts taken
from holy books were placed on the walls and bound around the sick
man's members. If these failed, recourse was had to the influence
of the mamit, which the evil powers were unable to resist. On a tablet,
written in the Accadian language only, the Assyrian version being
taken, however, was found the following:\ 

\begin{enumerate}
\item \begin{flushleft}Take a white cloth. In it place the mamit, \end{flushleft}
\item \begin{flushleft}in the sick man's right hand. \end{flushleft}
\item \begin{flushleft}Take a black cloth, \end{flushleft}
\item \begin{flushleft}wrap it around his left hand. \end{flushleft}
\item \begin{flushleft}Then all the evil spirits (a long list of them is
given) \end{flushleft}
\item \begin{flushleft}and the sins which he has committed \end{flushleft}
\item \begin{flushleft}shall quit their hold of him \end{flushleft}
\item \begin{flushleft}and shall never return.\end{flushleft}
\end{enumerate}
The symbolism of the black cloth in the left hand seems evident. The
dying man repents of his former evil deeds, and he puts his trust
in holiness, symbolized by the white cloth in his right hand. Then
follow some obscure lines about the spirits:\ 

\begin{enumerate}
\item \begin{flushleft}Their heads shall remove from his head.\end{flushleft}
\item \begin{flushleft}Their heads shall let go his hands.\end{flushleft}
\item \begin{flushleft}Their feet shall depart from his feet.\end{flushleft}
\end{enumerate}
Which perhaps may be explained thus: we learn from another tablet
that the various classes of evil spirits troubled different parts
of the body; some injured the head, some the hands and the feet, \textit{etc}.,
therefore the passage before may mean {}``the spirits whose power
is over the hand shall loose their hands from his,''\ \textit{etc}.
{}``But,''\ concludes Talbot, {}``I can offer no decided opinion
upon such obscure points of their superstition.''%
\footnote{\emph{Records of the Past} (editor, Samuel Birch), Vol. III., p.\ 139.%
}

In regard to evil spirits, as elsewhere, the number seven had a peculiar
significance, it being held that that number of spirits might enter
into a man together. Talbot has translated%
\footnote{\emph{Ibid}., Vol. V., p.\ 16.%
} a {}``wild chant''\ which he names {}``The Song of the Seven
Spirits.''

\begin{enumerate}
\item \begin{flushleft}There are seven! There are seven!\end{flushleft}
\item \begin{flushleft}In the depths of the ocean there are seven!\end{flushleft}
\item \begin{flushleft}In the heights of the heaven there are seven!\end{flushleft}
\item \begin{flushleft}In the ocean stream in a palace they were born.\end{flushleft}
\item \begin{flushleft}Male they are not: female they are not!\end{flushleft}
\item \begin{flushleft}Wives they have not! Children are not born to them!\end{flushleft}
\item \begin{flushleft}Rules they have not! Government they know not!\end{flushleft}
\item \begin{flushleft}Prayers they hear not!\end{flushleft}
\item \begin{flushleft}There are seven! There are seven! Twice over there
are seven!\end{flushleft}
\end{enumerate}
The tablets make frequent allusion to these seven spirits. One starts
thus:\ 

\begin{enumerate}
\item \begin{flushleft}The god (------)\ shall stand by his bedside;\end{flushleft}
\item \begin{flushleft}These seven evil spirits he shall root out and shall
expel them from his body,\end{flushleft}
\item \begin{flushleft}and these seven shall never return to the sick man
again.%
\footnote{Quoted in \emph{Records of the Past}, Vol. III., p.\ 143, from the
\emph{Translations of the Society of Biblical Archeology}, \textit{\emph{vol}}.
II., p.\ 58.%
}\end{flushleft}
\end{enumerate}
Altogether similar are the exorcisms intended to ward off disease.
Professor Sayce has published translations of some of these.%
\footnote{\emph{Records of the Past}, \textit{\emph{vol}}. L, p.\ 131.%
} Each of these ends with the same phrase, and they differ only in
regard to the particular maladies from which freedom is desired. One
reads:\ 

\begin{quote}
{}``From wasting, from want of health, from the evil spirit of the
ulcer, from the spreading quinsy of the gullet, from the violent ulcer,
from the noxious ulcer, may the king of heaven preserve, may the king
of earth preserve.''
\end{quote}
{}

Another is phrased thus:\ 

\begin{quote}
{}``From the cruel spirit of the head, from the strong spirit of
the head, from the head spirit that departs not, from the head spirit
that comes not forth, from the head spirit that will not go, from
the noxious head spirit, may the king of heaven preserve, may the
king of earth preserve.''
\end{quote}
{}

As to omens having to do with the affairs of everyday life the number
is legion. For example, Moppert has published, in the \textit{Journal}
\textit{Asiatique},%
\footnote{\emph{Ibid}., \textit{\emph{vol}}. V., p.\ 171.%
} the translation of a tablet which contains on its two sides several
scores of birth-portents, a few of which maybe quoted at random:\ 

{}``When a woman bears a child and it has the ears of a lion, a strong
king is in the country.'' {}``When a woman bears a child and it
has a bird's beak, that country is oppressed.'' {}``When a woman
bears a child and its right hand is wanting, that country goes to
destruction.'' {}``When a woman bears a child and its feet are wanting,
the roads of the country are cut; that house is destroyed.'' {}``When
a woman bears a child and at the time of its birth its beard is grown,
floods are in the country.'' {}``When a woman bears a child and
at the time of its birth its mouth is open and speaks, there is pestilence
in the country, the Air-god inundates the crops of the country, injury
in the country is caused.''

Some of these portents, it will be observed, are not in much danger
of realization, and it is curious to surmise by what stretch of the
imagination they can have been invented. There is, for example, on
the same tablet just quoted, one reference which assures us that {}``when
a sheep bears a lion the forces march multitudinously; the king has
not a rival.'' There are other omens, however, that are so easy of
realization as to lead one to suppose that any Babylonian who regarded
all the superstitious signs must have been in constant terror. Thus
a tablet translated by Professor Sayce%
\footnote{\emph{Ibid}., \textit{\emph{vol}}.\ V., p.\ 169.%
} gives a long list of omens furnished by dogs, in which we are assured
that:\ 

\begin{enumerate}
\item \begin{flushleft}If a yellow dog enters into the palace, exit from
that palace will be baleful.\end{flushleft}
\item \begin{flushleft}If a dog to the palace goes, and on a throne lies
down, that palace is burned.\end{flushleft}
\item \begin{flushleft}If a black dog into a temple enters, the foundation
of that temple is not stable.\end{flushleft}
\item \begin{flushleft}If female dogs one litter bear, destruction to the
city.\end{flushleft}
\end{enumerate}
{}

It is needless to continue these citations, since they but reiterate
endlessly the same story. It is interesting to recall, however, that
the observations of animate nature, which were doubtless superstitious
in their motive, had given the Babylonians some inklings of a knowledge
of classification. Thus, according to Menant,%
\footnote{Joachim Menant, \textit{La} \textit{Biblioth\`{e}que} \textit{du}
\textit{Palais} \textit{de} \textit{Ninive}, Paris, 1880.%
} some of the tablets from Nineveh, which are written, as usual, in
both the Sumerian and Assyrian languages, and which, therefore, like
practically all Assyrian books, draw upon the knowledge of old Babylonia,
give lists of animals, making an attempt at classification. The dog,
lion, and wolf are placed in one category; the ox, sheep, and goat
in another; the dog family itself is divided into various races, as
the domestic dog, the coursing dog, the small dog, the dog of Elan,
\textit{etc}. Similar attempts at classification of birds are found.
Thus, birds of rapid flight, sea-birds, and marsh-birds are differentiated.
Insects are classified according to habit; those that attack plants,
animals, clothing, or wood. Vegetables seem to be classified according
to their usefulness. One tablet enumerates the uses of wood according
to its adaptability for timber-work of palaces, or construction of
vessels, the making of implements of husbandry, or even furniture.
Minerals occupy a long series in these tablets. They are classed according
to their qualities, gold and silver occupying a division apart; precious
stones forming another series. Our Babylonians, then, must be credited
with the development of a rudimentary science of natural history.


\section*{\raggedright BABYLONIAN MEDICINE}

\addcontentsline{toc}{section}{BABYLONIAN MEDICINE}

We have just seen that medical practice in the Babylonian world was
strangely under the cloud of superstition. But it should be understood
that our estimate, through lack of correct data, probably does much
less than justice to the attainments of the physician of the time.
As already noted, the existing tablets chance not to throw much light
on the subject. It is known, however, that the practitioner of medicine
occupied a position of some authority and responsibility. The proof
of this is found in the clauses relating to the legal status of the
physician which are contained in the now famous code%
\footnote{\emph{Code of Khamurabi}. This famous inscription is on a block of
black diorite nearly eight feet in height. It was discovered at Susa
by the French expedition under M.\ de Morgan, in December, 1902.
We quote the translation given in \emph{The Historians'\ History
of the World}, edited by Henry Smith Williams, London and New York,
1904, Vol. I, p.\ 510.%
} of the Babylonian King Khamurabi, who reigned about 2300 years before
our era. These clauses, though throwing no light on the scientific
attainments of the physician of the period, are too curious to be
omitted. They are clauses 215 to 227 of the celebrated code, and are
as follows:\ 

215. If a doctor has treated a man for a severe wound with a lancet
of bronze and has cured the man, or has opened a tumor with a bronze
lancet and has cured the man's eye, he shall receive ten shekels of
silver.

216. If it was a freedman, he shall receive five shekels of silver.

217. If it was a man's slave, the owner of the slave shall give the
doctor two shekels of silver.

218. If a physician has treated a free-born man for a severe wound
with a lancet of bronze and has caused the man to die, or has opened
a tumor of the man with a lancet of bronze and has destroyed his eye,
his hands one shall cut off.

219. If the doctor has treated the slave of a freedman for a severe
wound with a bronze lancet and has caused him to die, he shall give
back slave for slave.

220. If he has opened his tumor with a bronze lancet and has ruined
his eye, he shall pay the half of his price in money.

221. If a doctor has cured the broken limb of a man, or has healed
his sick body, the patient shall pay the doctor five shekels of silver.

222. If it was a freedman, he shall give three shekels of silver.

223. If it was a man's slave, the owner of the slave shall give two
shekels of silver to the doctor.

224. If the doctor of oxen and asses has treated an ox or an ass for
a grave wound and has cured it, the owner of the ox or the ass shall
give to the doctor as his pay one-sixth of a shekel of silver.

225. If he has treated an ox or an ass for a severe wound and has
caused its death, he shall pay one-fourth of its price to the owner
of the ox or the ass.

226. If a barber-surgeon, without consent of the owner of a slave,
has branded the slave with an indelible mark, one shall cut off the
hands of that barber.

227. If any one deceive the surgeon-barber and make him brand a slave
with an indelible mark, one shall kill that man and bury him in his
house. The barber shall swear, {}``I did not mark him wittingly,''\ and
he shall be guiltless.


\section*{\raggedright ESTIMATES OF BABYLONIAN SCIENCE}

\addcontentsline{toc}{section}{ESTIMATES OF BABYLONIAN\\
SCIENCE}

Before turning from the Oriental world it is perhaps worth while to
attempt to estimate somewhat specifically the world-influence of the
name, Babylonian science. Perhaps we cannot better gain an idea as
to the estimate put upon that science by the classical world than
through a somewhat extended quotation from a classical author. Diodorus
\textit{\emph{Siculus}}, who, as already noted, lived at about the
time of Augustus, and who, therefore, scanned in perspective the entire
sweep of classical Greek history, has left us a striking summary which
is doubly valuable because of its comparisons of Babylonian with Greek
influence. Having viewed the science of Babylonia in the light of
the interpretations made possible by the recent study of original
documents, we are prepared to draw our own conclusions from the statements
of the Greek historian. Here is his estimate in the words of the quaint
translation made by Philemon Holland in the year 1700:%
\footnote{The \emph{Historical Library} of Diodorus \textit{\emph{Siculus}},
p.\ 519.%
}

\begin{quotation}
{}``They being the most ancient Babylonians, hold the same station
and dignity in the Common-wealth as the Egyptian Priests do in Egypt:
For being deputed to Divine Offices, they spend all their Time in
the study of Philosophy, and are especially famous for the Art of
Astrology. They are mightily given to Divination, and foretel future
Events, and imploy themselves either by Purifications, Sacrifices,
or other Inchantments to avert Evils, or procure good Fortune and
Success. They are skilful likewise in the Art of Divination, by the
flying of Birds, and interpreting of Dreams and Prodigies: And are
reputed as true Oracles (in declaring what will come to pass)\ by
their exact and diligent viewing the Intrals of the Sacrifices. But
they attain not to this Knowledge in the same manner as the Grecians
do; for the Chaldeans learn it by Tradition from their Ancestors,
the Son from the Father, who are all in the mean time free from all
other publick Offices and Attendances; and because their Parents are
their Tutors, they both learn every thing without Envy, and rely with
more confidence upon the truth of what is taught them; and being train'd
up in this Learning, from their very Childhood, they become most famous
Philosophers, (that Age being most capable of Learning, wherein they
spend much of their time). But the Grecians for the most part come
raw to this study, unfitted and unprepar'd, and are long before they
attain to the Knowledge of this Philosophy: And after they have spent
some small time in this Study, they are many times call'd off and
forc'd to leave it, in order to get a Livelihood and Subsistence.
And although some few do industriously apply themselves to Philosophy,
yet for the sake of Gain, these very Men are opinionative, and ever
and anon starting new and high Points, and never fix in the steps
of their Ancestors. But the Barbarians keeping constantly close to
the same thing, attain to a perfect and distinct Knowledge in every
particular.

{}``But the Grecians, cunningly catching at all Opportunities of
Gain, make new Sects and Parties, and by their contrary Opinions wrangling
and quarelling concerning the chiefest Points, lead their Scholars
into a Maze; and being uncertain and doubtful what to pitch upon for
certain truth, their Minds are fluctuating and in suspence all the
days of their Lives, and unable to give a certain assent unto any
thing. For if any Man will but examine the most eminent Sects of the
Philosophers, he shall find them much differing among themselves,
and even opposing one another in the most weighty parts of their Philosophy.
But to return to the Chaldeans, they hold that the World is eternal,
which had neither any certain Beginning, nor shall have any End; but
all agree, that all things are order'd, and this beautiful Fabrick
is supported by a Divine Providence, and that the Motions of the Heavens
are not perform'd by chance and of their own accord, but by a certain
and determinate Will and Appointment of the Gods.

{}``Therefore from a long observation of the Stars, and an exact
Knowledge of the motions and influences of every one of them, wherein
they excel all others, they fortel many things that are to come to
pass.

{}``They say that the Five Stars which some call Planets, but they
Interpreters, are most worthy of Consideration, both for their motions
and their remarkable influences, especially that which the Grecians
call Saturn. The brightest of them all, and which often portends many
and great Events, they call Sol, the other Four they name Mars, Venus,
Mercury, and Jupiter, with our own Country Astrologers. They give
the Name of Interpreters to these Stars, because these only by a peculiar
Motion do portend things to come, and instead of Jupiters, do declare
to Men before-hand the good-will of the Gods; whereas the other Stars
(not being of the number of the Planets)\ have a constant ordinary
motion. Future Events (they say)\ are pointed at sometimes by their
Rising, and sometimes by their Setting, and at other times by their
Colour, as may be experienc'd by those that will diligently observe
it; sometimes foreshewing Hurricanes, at other times Tempestuous Rains,
and then again exceeding Droughts. By these, they say, are often portended
the appearance of Comets, Eclipses of the Sun and Moon, Earthquakes
and all other the various Changes and remarkable effects in the Air,
boding good and bad, not only to Nations in general, but to Kings
and Private Persons in particular. Under the course of these Planets,
they say are Thirty Stars, which they call Counselling Gods, half
of whom observe what is done under the Earth, and the other half take
notice of the actions of Men upon the Earth, and what is transacted
in the Heavens. Once every Ten Days space (they say) one of the highest
Order of these Stars descends to them that are of the lowest, like
a Messenger sent from them above; and then again another ascends from
those below to them above, and that this is their constant natural
motion to continue for ever. The chief of these Gods, they say, are
Twelve in number, to each of which they attribute a Month, and one
Sign of the Twelve in the Zodiack.

{}``Through these Twelve Signs the Sun, Moon, and the other Five
Planets run their Course. The Sun in a Years time, and the Moon in
the space of a Month. To every one of the Planets they assign their
own proper Courses, which are perform'd variously in lesser or shorter
time according as their several motions are quicker or slower. These
Stars, they say, have a great influence both as to good and bad in
Mens Nativities; and from the consideration of their several Natures,
may be foreknown what will befal Men afterwards. As they foretold
things to come to other Kings formerly, so they did to Alexander who
conquer'd Darius, and to his Successors Antigonus and Seleucus Nicator;
and accordingly things fell out as they declar'd; which we shall relate
particularly hereafter in a more convenient time. They tell likewise
private Men their Fortunes so certainly, that those who have found
the thing true by Experience, have esteem'd it a Miracle, and above
the reach of man to perform. Out of the Circle of the Zodiack they
describe Four and Twenty Stars, Twelve towards the North Pole, and
as many to the South.

{}``Those which we see, they assign to the living; and the other
that do not appear, they conceive are Constellations for the Dead;
and they term them Judges of all things. The Moon, they say, is in
the lowest Orb; and being therefore next to the Earth (because she
is so small), she finishes her Course in a little time, not through
the swiftness of her Motion, but the shortness of her Sphear. In that
which they affirm (that she has but a borrow'd light, and that when
she is eclips'd, it's caus'd by the interposition of the shadow of
the Earth)\ they agree with the Grecians.

{}``Their Rules and Notions concerning the Eclipses of the Sun are
but weak and mean, which they dare not positively foretel, nor fix
a certain time for them. They have likewise Opinions concerning the
Earth peculiar to themselves, affirming it to resemble a Boat, and
to be hollow, to prove which, and other things relating to the frame
of the World, they abound in Arguments; but to give a particular Account
of 'em, we conceive would be a thing foreign to our History. But this
any Man may justly and truly say, That the Chaldeans far exceed all
other Men in the Knowledge of Astrology, and have study'd it most
of any other Art or Science: But the number of years during which
the Chaldeans say, those of their Profession have given themselves
to the study of this natural Philosophy, is incredible; for when Alexander
was in Asia, they reckon'd up Four Hundred and Seventy Thousand Years
since they first began to observe the Motions of the Stars.''
\end{quotation}
{}

Let us now supplement this estimate of Babylonian influence with another
estimate written in our own day, and quoted by one of the most recent
historians of Babylonia and Assyria.%
\footnote{George S.\ Goodspeed, Ph.D., \emph{History of the Babylonians and
Assyrians}, New York, 1902.%
} The estimate in question is that of Canon Rawlinson in his \emph{Great
Oriental Monarchies}.%
\footnote{George Rawlinson, \emph{Great Oriental Monarchies}, (second edition,
London, 1871), Vol.\ III., \textit{\emph{pp}}.\ 75 \textit{ff}.%
} Of Babylonia he says:\ 

\begin{quote}
{}``Hers was apparently the genius which excogitated an alphabet;
worked out the simpler problems of arithmetic; invented implements
for measuring the lapse of time; conceived the idea of raising enormous
structures with the poorest of all materials, clay; discovered the
art of polishing, boring, and engraving gems; reproduced with truthfulness
the outlines of human and animal forms; attained to high perfection
in textile fabrics; studied with success the motions of the heavenly
bodies; conceived of grammar as a science; elaborated a system of
law; saw the value of an exact chronology---in almost every branch
of science made a beginning, thus rendering it comparatively easy
for other nations to proceed with the superstructure.... It was from
the East, not from Egypt, that Greece derived her architecture, her
sculpture, her science, her philosophy, her mathematical knowledge---in
a word, her intellectual life. And Babylon was the source to which
the entire stream of Eastern civilization may be traced. It is scarcely
too much to say that, but for Babylon, real civilization might not
yet have dawned upon the earth.''
\end{quote}
{}

Considering that a period of almost two thousand years separates the
times of writing of these two estimates, the estimates themselves
are singularly in unison. They show that the greatest of Oriental
nations has not suffered in reputation at the hands of posterity.
It is indeed almost impossible to contemplate the monuments of Babylonian
and Assyrian civilization that are now preserved in the European and
American museums without becoming enthusiastic. That certainly was
a wonderful civilization which has left us the tablets on which are
inscribed the laws of a Khamurabi on the one hand, and the art treasures
of the palace of an Asshurbanipal on the other. Yet a candid consideration
of the scientific attainments of the Babylonians and Assyrians can
scarcely arouse us to a like enthusiasm. In considering the subject
we have seen that, so far as pure science is concerned, the efforts
of the Babylonians and Assyrians chiefly centred about the subjects
of astrology and magic. With the records of their ghost-haunted science
fresh in mind, one might be forgiven for a momentary desire to take
issue with Canon Rawlinson's words. We are assured that the scientific
attainments of Europe are almost solely to be credited to Babylonia
and not to Egypt, but we should not forget that Plato, the greatest
of the Greek thinkers, went to Egypt and not to Babylonia to pursue
his studies when he wished to penetrate the secrets of Oriental science
and philosophy. Clearly, then, classical Greece did not consider Babylonia
as having a monopoly of scientific knowledge, and we of to-day, when
we attempt to weigh the new evidence that has come to us in recent
generations with the Babylonian records themselves, find that some,
at least, of the heritages for which Babylonia has been praised are
of more than doubtful value. Babylonia, for example, gave us our seven-day
week and our system of computing by twelves. But surely the world
could have got on as well without that magic number seven; and after
some hundreds of generations we are coming to feel that the decimal
system of the Egyptians has advantages over the duodecimal system
of the Babylonians. Again, the Babylonians did not invent the alphabet;
they did not even accept it when all the rest of the world had recognized
its value. In grammar and arithmetic, as with astronomy, they seemed
not to have advanced greatly, if at all, upon the Egyptians. One field
in which they stand out in startling pre-eminence is the field of
astrology; but this, in the estimate of modern thought, is the very
negation of science. Babylonia impressed her superstitions on the
Western world, and when we consider the baleful influence of these
superstitions, we may almost question whether we might not reverse
Canon Rawlinson's estimate and say that perhaps but for Babylonia
real civilization, based on the application of true science, might
have dawned upon the earth a score of centuries before it did. Yet,
after all, perhaps this estimate is unjust. Society, like an individual
organism, must creep before it can walk, and perhaps the Babylonian
experiments in astrology and magic, which European civilization was
destined to copy for some three or four thousand years, must have
been made a part of the necessary evolution of our race in one place
or in another. That thought, however, need not blind us to the essential
fact, which the historian of science must needs admit, that for the
Babylonian, despite his boasted culture, science spelled superstition.


\chapter*{\raggedright IV. THE DEVELOPMENT OF THE ALPHABET}

\addcontentsline{toc}{chapter}{IV. THE DEVELOPMENT OF THE\\
ALPHABET}

\markboth{A HISTORY OF SCIENCE, BOOK I}{IV. THE ALPHABET}

Before we turn specifically to the new world of the west, it remains
to take note of what may perhaps be regarded as the very greatest
achievement of ancient science. This was the analysis of speech sounds,
and the resulting development of a system of alphabetical writing.
To comprehend the series of scientific inductions which led to this
result, we must go back in imagination and trace briefly the development
of the methods of recording thought by means of graphic symbols. In
other words, we must trace the evolution of the art of writing. In
doing so we cannot hold to national lines as we have done in the preceding
two chapters, though the efforts of the two great scientific nations
just considered will enter prominently into the story.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth,
  height=0.90\paperwidth,
  keepaspectratio]{1hsci10-Wil1Sc86}\end{center}

\noindent \begin{center}\noun{\small The Moabite Stone}\end{center}{\small \par}

\noindent \emph{\footnotesize (With one possible exception the oldest
known example of the Ph\oe{}nician writing. It shows an inscription
of Mesha, king of Moab, and dates from early in the ninth century,
B.C.) }
\end{figure}
The familiar Greek legend assures us that a Ph\oe{}nician named Kadmus
was the first to bring a knowledge of letters into Europe. An elaboration
of the story, current throughout classical times, offered the further
explanation that the Ph\oe{}nicians had in turn acquired the art
of writing from the Egyptians or Babylonians. Knowledge as to the
true origin and development of the art of writing did not extend in
antiquity beyond such vagaries as these. Nineteenth-century studies
gave the first real clews to an understanding of the subject. These
studies tended to authenticate the essential fact on which the legend
of Kadmus was founded; to the extent, at least, of making it probable
that the later Grecian alphabet was introduced from Ph\oe{}nicia---though
not, of course, by any individual named Kadmus, the latter being,
indeed, a name of purely Greek origin. Further studies of the past
generation tended to corroborate the ancient belief as to the original
source of the Ph\oe{}nician alphabet, but divided scholars between
two opinions: the one contending that the Egyptian hieroglyphics were
the source upon which the Ph\oe{}nicians drew; and the other contending
with equal fervor that the Babylonian wedge character must be conceded
that honor.

But, as has often happened in other fields after years of acrimonious
controversy, a new discovery or two may suffice to show that neither
contestant was right. After the Egyptologists of the school of De
Rouge%
\footnote{Vicomte E.\ de Rouge, \emph{Memoire sur l'Origine} \textit{\'{E}gyptienne}
\emph{de l'Alphabet Phinicien}, Paris, 1874.%
} thought they had demonstrated that the familiar symbols of the Ph\oe{}nician
alphabet had been copied from that modified form of Egyptian hieroglyphics
known as the hieratic writing, the Assyriologists came forward to
prove that certain characters of the Babylonian syllabary also show
a likeness to the alphabetical characters that seemingly could not
be due to chance. And then, when a settlement of the dispute seemed
almost hopeless, it was shown through the Egyptian excavations that
characters even more closely resembling those in dispute had been
in use all about the shores of the Mediterranean, quite independently
of either Egyptian or Assyrian writings, from periods so ancient as
to be virtually prehistoric.

Coupled with this disconcerting discovery are the revelations brought
to light by the excavations at the sites of Knossos and other long-buried
cities of the island of Crete.%
\footnote{See the various publications of Mr.\ Arthur Evans.%
} These excavations, which are still in progress, show that the art
of writing was known and practised independently in Crete before that
cataclysmic overthrow of the early Greek civilization which arch\ae{}ologists
are accustomed to ascribe to the hypothetical invasion of the Dorians.
The significance of this is that the art of writing was known in Europe
long before the advent of the mythical Kadmus. But since the early
Cretan scripts are not to be identified with the scripts used in Greece
in historical times, whereas the latter are undoubtedly of lineal
descent from the Ph\oe{}nician alphabet, the validity of the Kadmus
legend, in a modified form, must still be admitted.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc88}\end{center}

\noindent \begin{center}\noun{\small Mexican Picture-Writing}\end{center}{\small \par}

\noindent \emph{\footnotesize (Probably of the fourteenth or fifteenth
century, A.D. The original is now M.S. 3773 of the Vatican Library,
Rome. Reproduced from Williams'} {\footnotesize History of the Art
of Writing}\emph{\footnotesize .) }
\end{figure}
As has just been suggested, the new knowledge, particularly that which
related to the great antiquity of characters similar to the Ph\oe{}nician
alphabetical signs, is somewhat disconcerting. Its general trend,
however, is quite in the same direction with most of the new arch\ae{}ological
knowledge of recent decades----that is to say, it tends to emphasize
the idea that human civilization in most of its important elaborations
is vastly older than has hitherto been supposed. It may be added,
however, that no definite clews are as yet available that enable us
to fix even an approximate date for the origin of the Ph\oe{}nician
alphabet. The signs, to which reference has been made, may well have
been in existence for thousands of years, utilized merely as property
marks, symbols for counting and the like, before the idea of setting
them aside as phonetic symbols was ever conceived. Nothing is more
certain, in the judgment of the present-day investigator, than that
man learned to write by slow and painful stages. It is probable that
the conception of such an analysis of speech sounds as would make
the idea of an alphabet possible came at a very late stage of social
evolution, and as the culminating achievement of a long series of
improvements in the art of writing. The precise steps that marked
this path of intellectual development can for the most part be known
only by inference; yet it is probable that the main chapters of the
story may be reproduced with essential accuracy.


\section*{\raggedright FIRST STEPS}

\addcontentsline{toc}{section}{FIRST STEPS}

For the very first chapters of the story we must go back in imagination
to the prehistoric period. Even barbaric man feels the need of self-expression,
and strives to make his ideas manifest to other men by pictorial signs.
The cave-dwellers scratched pictures of men and animals on the surface
of a reindeer horn or mammoth tusk as mementos of his prowess. The
American Indian does essentially the same thing to-day, making pictures
that crudely record his successes in war and the chase. The Northern
Indian had got no farther than this when the white man discovered
America; but the Aztecs of the Southwest and the Maya people of Yucatan
had carried their picture-making to a much higher state of elaboration.%
\footnote{Aztec and Maya writing. These pictographs are still in the main undecipherable,
and opinions differ as to the exact stage of development which they
represent.%
} They had developed systems of pictographs or hieroglyphics that would
doubtless in the course of generations have been elaborated into alphabetical
systems, had not the Europeans cut off the civilization of which they
were the highest exponents.

What the Aztec and Maya were striving towards in the sixteenth century
A.D., various Oriental nations had attained at least five or six thousand
years earlier. In Egypt at the time of the pyramid-builders, and in
Babylonia at the same epoch, the people had developed systems of writing
that enabled them not merely to present a limited range of ideas pictorially,
but to express in full elaboration and with finer shades of meaning
all the ideas that pertain to highly cultured existence. The man of
that time made records of military achievements, recorded the transactions
of every-day business life, and gave expression to his moral and spiritual
aspirations in a way strangely comparable to the manner of our own
time. He had perfected highly elaborate systems of writing.


\section*{\raggedright EGYPTIAN WRITING}

\addcontentsline{toc}{section}{EGYPTIAN WRITING}

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc90}\end{center}

\noindent \begin{center}\noun{\small Reproduction of a Fragment
of the Egyption Book of the Dead}\end{center}{\small \par}

\noindent \emph{\footnotesize (Reproduced from Williams'} {\footnotesize History
of the Art of Writing}\emph{\footnotesize .) }
\end{figure}
Of the two ancient systems of writing just referred to as being in
vogue at the so-called dawnings of history, the more picturesque and
suggestive was the hieroglyphic system of the Egyptians. This is a
curiously conglomerate system of writing, made up in part of symbols
reminiscent of the crudest stages of picture-writing, in part of symbols
having the phonetic value of syllables, and in part of true alphabetical
letters. In a word, the Egyptian writing represents in itself the
elements of the various stages through which the art of writing has
developed.%
\footnote{E.\ A.\ Wallace Budge's \emph{First Steps in Egyptian}, London,
1895, is an excellent elementary work on the Egyptian writing. Professor
Erman's \emph{Egyptian Grammar}, London, 1894, is the work of perhaps
the foremost living Egyptologist.%
} We must conceive that new features were from time to time added to
it, while the old features, curiously enough, were not given up.

Here, for example, in the midst of unintelligible lines and pot-hooks,
are various pictures that are instantly recognizable as representations
of hawks, lions, ibises, and the like. It can hardly be questioned
that when these pictures were first used calligraphically they were
meant to represent the idea of a bird or animal. In other words, the
first stage of picture-writing did not go beyond the mere representation
of an eagle by the picture of an eagle. But this, obviously, would
confine the presentation of ideas within very narrow limits. In due
course some inventive genius conceived the thought of symbolizing
a picture. To him the outline of an eagle might represent not merely
an actual bird, but the thought of strength, of courage, or of swift
progress. Such a use of symbols obviously extends the range of utility
of a nascent art of writing. Then in due course some wonderful psychologist---or
perhaps the joint efforts of many generations of psychologists---made
the astounding discovery that the human voice, which seems to flow
on in an unbroken stream of endlessly varied modulations and intonations,
may really be analyzed into a comparatively limited number of component
sounds---into a few hundreds of syllables. That wonderful idea conceived,
it was only a matter of time until it would occur to some other enterprising
genius that by selecting an arbitrary symbol to represent each one
of these elementary sounds it would be possible to make a written
record of the words of human speech which could be reproduced---rephonated---by
some one who had never heard the words and did not know in advance
what this written record contained. This, of course, is what every
child learns to do now in the primer class, but we may feel assured
that such an idea never occurred to any human being until the peculiar
forms of pictographic writing just referred to had been practised
for many centuries. Yet, as we have said, some genius of prehistoric
Egypt conceived the idea and put it into practical execution, and
the hieroglyphic writing of which the Egyptians were in full possession
at the very beginning of what we term the historical period made use
of this phonetic system along with the ideographic system already
described.

So fond were the Egyptians of their pictorial symbols used ideographically
that they clung to them persistently throughout the entire period
of Egyptian history. They used symbols as phonetic equivalents very
frequently, but they never learned to depend upon them exclusively.
The scribe always interspersed his phonetic signs with some other
signs intended as graphic aids. After spelling a word out in full,
he added a picture, sometimes even two or three pictures, representative
of the individual thing, or at least of the type of thing to which
the word belongs. Two or three illustrations will make this clear.

Thus \emph{qeften}, monkey, is spelled out in full, but the picture
of a monkey is added as a determinative; second, \emph{qenu}, cavalry,
after being spelled, is made unequivocal by the introduction of a
picture of a horse; third, \emph{temati}, wings, though spelled elaborately,
has pictures of wings added; and fourth, \emph{tatu}, quadrupeds,
after being spelled, has a picture of a quadruped, and then the picture
of a hide, which is the usual determinative of a quadruped, followed
by three dashes to indicate the plural number.

It must not be supposed, however, that it was a mere whim which led
the Egyptians to the use of this system of determinatives. There was
sound reason back of it. It amounted to no more than the expedient
we adopt when we spell {}``to,''\ {}``two,''\ or {}``too,''\ in
indication of a single sound with three different meanings. The Egyptian
language abounds in words having more than one meaning, and in writing
these it is obvious that some means of distinction is desirable. The
same thing occurs even more frequently in the Chinese language, which
is monosyllabic. The Chinese adopt a more clumsy expedient, supplying
a different symbol for each of the meanings of a syllable; so that
while the actual word-sounds of their speech are only a few hundreds
in number, the characters of their written language mount high into
the thousands.


\section*{\raggedright BABYLONIAN WRITING}

\addcontentsline{toc}{section}{BABYLONIAN WRITING}

While the civilization of the Nile Valley was developing this extraordinary
system of hieroglyphics, the inhabitants of Babylonia were practising
the art of writing along somewhat different lines. It is certain that
they began with picture-making, and that in due course they advanced
to the development of the syllabary; but, unlike their Egyptian cousins,
the men of Babylonia saw fit to discard the old system when they had
perfected a better one.%
\footnote{Extant examples of Babylonian and Assyrian writing give opportunity
to compare earlier and later systems, so the fact of evolution from
the pictorial to the phonetic system rests on something more than
mere theory.%
} So at a very early day their writing---as revealed to us now through
the recent excavations---had ceased to have that pictorial aspect
which distinguishes the Egyptian script. What had originally been
pictures of objects---fish, houses, and the like---had come to be
represented by mere aggregations of wedge-shaped marks. As the writing
of the Babvlonians was chiefly inscribed on soft clay, the adaptation
of this wedge-shaped mark in lieu of an ordinary line was probably
a mere matter of convenience, since the sharp-cornered implement used
in making the inscription naturally made a wedge-shaped impression
in the clay. That, however, is a detail. The essential thing is that
the Babylonian had so fully analyzed the speech-sounds that he felt
entire confidence in them, and having selected a sufficient number
of conventional characters---each made up of wedge-shaped lines---to
represent all the phonetic sounds of his language, spelled the words
out in syllables and to some extent dispensed with the determinative
signs which, as we have seen, played so prominent a part in the Egyptian
writing. His cousins the Assyrians used habitually a system of writing
the foundation of which was an elaborate phonetic syllabary; a system,
therefore, far removed from the old crude pictograph, and in some
respects much more developed than the complicated Egyptian method;
yet, after all, a system that stopped short of perfection by the wide
gap that separates the syllabary from the true alphabet.

A brief analysis of speech sounds will aid us in understanding the
real nature of the syllabary. Let us take for consideration the consonantal
sound represented by the letter \emph{b}. A moment's consideration
will make it clear that this sound enters into a large number of syllables.
There are, for example, at least twenty vowel sounds in the English
language, not to speak of certain digraphs; that is to say, each of
the important vowels has from two to six sounds. Each of these vowel
sounds may enter into combination with the \emph{b} sound alone to
form three syllables; as \textit{ba}, \emph{ab}, \textit{bal}, \emph{be},
\emph{eb}, \emph{bel}, \textit{etc}. Thus there are at least sixty
\emph{b}-sound syllables. But this is not the end, for other consonantal
sounds may be associated in the syllables in such combinations as
\emph{bad}, \emph{bed}, \emph{bar}, \emph{bark}, \emph{cab}, \textit{etc}.
As each of the other twenty odd consonantal sounds may enter into
similar combinations, it is obvious that there are several hundreds
of fundamental syllables to be taken into account in any syllabic
system of writing. For each of these syllables a symbol must be set
aside and held in reserve as the representative of that particular
sound. A perfect syllabary, then, would require some hundred or more
of symbols to represent \emph{b} sounds alone; and since the sounds
for \emph{c}, \emph{d}, \emph{f}, and the rest are equally varied,
the entire syllabary would run into thousands of characters, almost
rivalling in complexity the Chinese system. But in practice the most
perfect syllabary, such as that of the Babylonians, fell short of
this degree of precision through ignoring the minor shades of sound;
just as our own alphabet is content to represent some thirty vowel
sounds by five letters, ignoring the fact that \emph{a}, for example,
has really half a dozen distinct phonetic values. By such slurring
of sounds the syllabary is reduced far below its ideal limits; yet
even so it retains three or four hundred characters.

In point of fact, such a work as Professor Delitzsch's \emph{Assyrian
Grammar}%
\footnote{Friedrich Delitzsch, \emph{Assyrischc Lesestucke} \textit{mit} \emph{grammatischen
Tabellen} \textit{und} \emph{vollstdndigem} \textit{Glossar} \emph{einfiihrung
in die assyrische} \textit{und} \emph{babylonische} \textit{Keilschrift}-\emph{litteratur}
\textit{bis} \textit{hinauf} \textit{zu} \emph{Hammurabi}, Leipzig,
1900.%
} presents signs for three hundred and thirty-four syllables, together
with sundry alternative signs and determinatives to tax the memory
of the would-be reader of Assyrian. Let us take for example a few
of the \emph{b} sounds. It has been explained that the basis of the
Assyrian written character is a simple wedge-shaped or arrow-head
mark. Variously repeated and grouped, these marks make up the syllabic
characters.

To learn some four hundred such signs as these was the task set, as
an equivalent of learning the \emph{abc}'s, to any primer class in
old Assyria in the long generations when that land was the culture
Centre of the world. Nor was the task confined to the natives of Babylonia
and Assyria alone. About the fifteenth century B.C., and probably
for a long time before and after that period, the exceedingly complex
syllabary of the Babylonians was the official means of communication
throughout western Asia and between Asia and Egypt, as we know from
the chance discovery of a collection of letters belonging to the Egyptian
king Khun-aten, preserved at Tel-el-Amarna. In the time of Ramses
the Great the Babylonian writing was in all probability considered
by a majority of the most highly civilized people in the world to
be the most perfect script practicable. Doubtless the average scribe
of the time did not in the least realize the waste of energy involved
in his labors, or ever suspect that there could be any better way
of writing.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1Sc96}\end{center}

\noindent \begin{center}\noun{\small Old Babylonian Inscription}\end{center}{\small \par}

\noindent \emph{\footnotesize (Date, about 4500 B.C. British Museum,
London. Reproduced from Williams'} {\footnotesize History of the Art
of Writing}\emph{\footnotesize .) }
\end{figure}
Yet the analysis of any one of these hundreds of syllables into its
component phonetic elements---had any one been genius enough to make
such analysis---would have given the key to simpler and better things.
But such an analysis was very hard to make, as the sequel shows. Nor
is the utility of such an analysis self-evident, as the experience
of the Egyptians proved. The vowel sound is so intimately linked with
the consonant---the con-sonant, implying this intimate relation in
its very name---that it seemed extremely difficult to give it individual
recognition. To set off the mere labial beginning of the sound by
itself, and to recognize it as an all-essential element of phonation,
was the feat at which human intelligence so long balked. The germ
of great things lay in that analysis. It was a process of simplification,
and all art development is from the complex to the simple. Unfortunately,
however, it did not seem a simplification, but rather quite the reverse.
We may well suppose that the idea of wresting from the syllabary its
secret of consonants and vowels, and giving to each consonantal sound
a distinct sign, seemed a most cumbersome and embarrassing complication
to the ancient scholars---that is to say, after the time arrived when
any one gave such an idea expression. We can imagine them saying:
{}``You will oblige us to use four signs instead of one to write
such an elementary syllable as `bard,' for example. Out upon such
endless perplexity!''\ Nor is such a suggestion purely gratuitous,
for it is an historical fact that the old syllabary continued to be
used in Babylon hundreds of years after the alphabetical system had
been introduced.%
\footnote{It does not appear that the Babylonians thcmselves ever gave up the
old system of writing, so long as they retained political autonomy.%
} Custom is everything in establishing our prejudices. The Japanese
to-day rebel against the introduction of an alphabet, thinking it
ambiguous.

Yet, in the end, conservatism always yields, and so it was with opposition
to the alphabet. Once the idea of the consonant had been firmly grasped,
the old syllabary was doomed, though generations of time might be
required to complete the obsequies---generations of time and the influence
of a new nation. We have now to inquire how and by whom this advance
was made.


\section*{\raggedright THE ALPHABET ACHIEVED}

\addcontentsline{toc}{section}{THE ALPHABET ACHIEVED}

We cannot believe that any nation could have vaulted to the final
stage of the simple alphabetical writing without tracing the devious
and difficult way of the pictograph and the syllabary. It is possible,
however, for a cultivated nation to build upon the shoulders of its
neighbors, and, profiting by the experience of others, to make sudden
leaps upward and onward. And this is seemingly what happened in the
final development of the art of writing. For while the Babylonians
and Assyrians rested content with their elaborate syllabary, a nation
on either side of them, geographically speaking, solved the problem,
which they perhaps did not even recognize as a problem; wrested from
their syllabary its secret of consonants and vowels, and by adopting
an arbitrary sign for each consonantal sound, produced that most wonderful
of human inventions, the alphabet.

The two nations credited with this wonderful achievement are the Ph\oe{}nicians
and the Persians. But it is not usually conceded that the two are
entitled to anything like equal credit. The Persians, probably in
the time of Cyrus the Great, used certain characters of the Babylonian
script for the construction of an alphabet; but at this time the Ph\oe{}nician
alphabet had undoubtedly been in use for some centuries, and it is
more than probable that the Persian borrowed his idea of an alphabet
from a Ph\oe{}nician source. And that, of course, makes all the difference.
Granted the idea of an alphabet, it requires no great reach of constructive
genius to supply a set of alphabetical characters; though even here,
it may be added parenthetically, a study of the development of alphabets
will show that mankind has all along had a characteristic propensity
to copy rather than to invent.

Regarding the Persian alphabet-maker, then, as a copyist rather than
a true inventor, it remains to turn attention to the Ph\oe{}nician
source whence, as is commonly believed, the original alphabet which
became {}``the mother of all existing alphabets''\ came into being.
It must be admitted at the outset that evidence for the Ph\oe{}nician
origin of this alphabet is traditional rather than demonstrative.
The Ph\oe{}nicians were the great traders of antiquity; undoubtedly
they were largely responsible for the transmission of the alphabet
from one part of the world to another, once it had been invented.
Too much credit cannot be given them for this; and as the world always
honors him who makes an idea fertile rather than the originator of
the idea, there can be little injustice in continuing to speak of
the Ph\oe{}nicians as the inventors of the alphabet. But the actual
facts of the case will probably never be known. For aught we know,
it may have been some dreamy-eyed Israelite, some Babylonian philosopher,
some Egyptian mystic, perhaps even some obscure Cretan, who gave to
the hard-headed Ph\oe{}nician trader this conception of a dismembered
syllable with its all-essential, elemental, wonder-working consonant.
But it is futile now to attempt even to surmise on such unfathomable
details as these. Suffice it that the analysis was made; that one
sign and no more was adopted for each consonantal sound of the Semitic
tongue, and that the entire cumbersome mechanism of the Egyptian and
Babylonian writing systems was rendered obsolescent. These systems
did not yield at once, to be sure; all human experience would have
been set at naught had they done so. They held their own, and much
more than held their own, for many centuries. After the Ph\oe{}nicians
as a nation had ceased to have importance; after their original script
had been endlessly modified by many alien nations; after the original
alphabet had made the conquest of all civilized Europe and of far
outlying portions of the Orient---the Egyptian and Babylonian scribes
continued to indite their missives in the same old pictographs and
syllables.

The inventive thinker must have been struck with amazement when, after
making the fullest analysis of speech-sounds of which he was capable,
he found himself supplied with only a score or so of symbols. Yet
as regards the consonantal sounds he had exhausted the resources of
the Semitic tongue. As to vowels, he scarcely considered them at all.
It seemed to him sufficient to use one symbol for each consonantal
sound. This reduced the hitherto complex mechanism of writing to so
simple a system that the inventor must have regarded it with sheer
delight. On the other hand, the conservative scholar doubtless thought
it distinctly ambiguous. In truth, it must be admitted that the system
was imperfect. It was a vast improvement on the old syllabary, but
it had its drawbacks. Perhaps it had been made a bit too simple; certainly
it should have had symbols for the vowel sounds as well as for the
consonants. Nevertheless, the vowel-lacking alphabet seems to have
taken the popular fancy, and to this day Semitic people have never
supplied its deficiencies save with certain dots and points.

Peoples using the Aryan speech soon saw the defect, and the Greeks
supplied symbols for several new sounds at a very early day.%
\footnote{See Isaac Taylor's \emph{History of the Alphabet; an Account of the
Origin and Development of Letters}, new \textit{\emph{edition}}, 2
\textit{\emph{vols}}., London, 1899.%
} But there the matter rested, and the alphabet has remained imperfect.
For the purposes of the English language there should certainly have
been added a dozen or more new characters. It is clear, for example,
that, in the interest of explicitness, we should have a separate symbol
for the vowel sound in each of the following syllables: \emph{bar},
\emph{bay}, \emph{bann}, \emph{ball}, to cite a single illustration.

There is, to be sure, a seemingly valid reason for not extending our
alphabet, in the fact that in multiplying syllables it would be difficult
to select characters at once easy to make and unambiguous. Moreover,
the conservatives might point out, with telling effect, that the present
alphabet has proved admirably effective for about three thousand years.
Yet the fact that our dictionaries supply diacritical marks for some
thirty vowels sounds to indicate the pronunciation of the words of
our every-day speech, shows how we let memory and guessing do the
work that might reasonably be demanded of a really complete alphabet.
But, whatever its defects, the existing alphabet is a marvellous piece
of mechanism, the result of thousands of years of intellectual effort.
It is, perhaps without exception, the most stupendous invention of
the human intellect within historical times---an achievement taking
rank with such great prehistoric discoveries as the use of articulate
speech, the making of a fire, and the invention of stone implements,
of the wheel and axle, and of picture-writing. It made possible for
the first time that education of the masses upon which all later progress
of civilization was so largely to depend.


\chapter*{\raggedright V.\ THE BEGINNINGS OF GREEK SCIENCE}

\addcontentsline{toc}{chapter}{V. THE BEGINNINGS OF GREEK\\
SCIENCE}

\markboth{A HISTORY OF SCIENCE, BOOK I}{V. GREEK SCIENCE}

Herodotus, the Father of History, tells us that once upon a time---which
time, as the modern \textit{\emph{computator}} shows us, was about
the year 590 B.C.---a war had risen between the Lydians and the \textit{\emph{Medes}}
and continued five years. {}``In these years the \textit{\emph{Medes}}
often discomfited the Lydians and the Lydians often discomfited the
\textit{\emph{Medes}} (and among other things they fought a battle
by night); and yet they still carried on the war with equally balanced
fortitude. In the sixth year a battle took place in which it happened,
when the fight had begun, that suddenly the day became night. And
this change of the day Thales, the Milesian, had foretold to the Ionians,
laying down as a limit this very year in which the change took place.
The Lydians, however, and the \textit{\emph{Medes}}, when they saw
that it had become night instead of day, ceased from their fighting
and were much more eager, both of them, that peace should be made
between them.''

This memorable incident occurred while Alyattus, father of Croesus,
was king of the Lydians. The modern astronomer, reckoning backward,
estimates this eclipse as occurring probably May 25th, 585 B.C. The
date is important as fixing a mile-stone in the chronology of ancient
history, but it is doubly memorable because it is the first recorded
instance of a predicted eclipse. Herodotus, who tells the story, was
not born until about one hundred years after the incident occurred,
but time had not dimmed the fame of the man who had performed the
necromantic feat of prophecy. Thales, the Milesian, thanks in part
at least to this accomplishment, had been known in life as first on
the list of the Seven Wise Men of Greece, and had passed into history
as the father of Greek philosophy. We may add that he had even found
wider popular fame through being named by Hippolytus, and then by
Father \AE{}sop, as the philosopher who, intent on studying the heavens,
fell into a well; {}``whereupon,''\ says Hippolytus, {}``a maid-servant
named Thratta laughed at him and said, `In his search for things in
the sky he does not see what is at his feet.'''

Such citations as these serve to bring vividly to mind the fact that
we are entering a new epoch of thought. Hitherto our studies have
been impersonal. Among Egyptians and Babylonians alike we have had
to deal with classes of scientific records, but we have scarcely come
across a single name. Now, however, we shall begin to find records
of the work of individual investigators. In general, from now on,
we shall be able to trace each great idea, if not to its originator,
at least to some one man of genius who was prominent in bringing it
before the world. The first of these vitalizers of thought, who stands
out at the beginnings of Greek history, is this same Thales, of Miletus.
His is not a very sharply defined personality as we look back upon
it, and we can by no means be certain that all the discoveries which
are ascribed to him are specifically his. Of his individuality as
a man we know very little. It is not even quite certain as to where
he was born; Miletus is usually accepted as his birthplace, but one
tradition makes him by birth a Phenician. It is not at all in question,
however, that by blood he was at least in part an Ionian Greek. It
will be recalled that in the seventh century B.C., when Thales was
born---and for a long time thereafter---the eastern shores of the
\AE{}gean Sea were quite as prominently the centre of Greek influence
as was the peninsula of Greece itself. Not merely Thales, but his
followers and disciples, Anaximander and Anaximenes, were born there.
So also was Herodotas, the Father of History, not to extend the list.
There is nothing anomalous, then, in the fact that Thales, the father
of Greek thought, was born and passed his life on soil that was not
geographically a part of Greece; but the fact has an important significance
of another kind. Thanks to his environment, Thales was necessarily
brought more or less in contact with Oriental ideas. There was close
commercial contact between the land of his nativity and the great
Babylonian capital off to the east, as also with Egypt. Doubtless
this association was of influence in shaping the development of Thales's
mind. Indeed, it was an accepted tradition throughout classical times
that the Milesian philosopher had travelled in Egypt, and had there
gained at least the rudiments of his knowledge of geometry. In the
fullest sense, then, Thales may be regarded as representing a link
in the chain of thought connecting the learning of the old Orient
with the nascent scholarship of the new Occident. Occupying this position,
it is fitting that the personality of Thales should partake somewhat
of mystery; that the scene may not be shifted too suddenly from the
vague, impersonal East to the individualism of Europe.

All of this, however, must not be taken as casting any doubt upon
the existence of Thales as a real person. Even the dates of his life---640
to 546 B.C.---may be accepted as at least approximately trustworthy;
and the specific discoveries ascribed to him illustrate equally well
the stage of development of Greek thought, whether Thales himself
or one of his immediate disciples were the discoverer. We have already
mentioned the feat which was said to have given Thales his great reputation.
That Thales was universally credited with having predicted the famous
eclipse is beyond question. That he actually did predict it in any
precise sense of the word is open to doubt. At all events, his prediction
was not based upon any such precise knowledge as that of the modern
astronomer. There is, indeed, only one way in which he could have
foretold the eclipse, and that is through knowledge of the regular
succession of preceding eclipses. But that knowledge implies access
on the part of some one to long series of records of practical observations
of the heavens. Such records, as we have seen, existed in Egypt and
even more notably in Babylonia. That these records were the source
of the information which established the reputation of Thales is an
unavoidable inference. In other words, the magical prevision of the
father of Greek thought was but a reflex of Oriental wisdom. Nevertheless,
it sufficed to establish Thales as the father of Greek astronomy.
In point of fact, his actual astronomical attainments would appear
to have been meagre enough. There is nothing to show that he gained
an inkling of the true character of the solar system. He did not even
recognize the sphericity of the earth, but held, still following the
Oriental authorities, that the world is a flat disk. Even his famous
cosmogonic guess, according to which water is the essence of all things
and the primordial element out of which the earth was developed, is
but an elaboration of the Babylonian conception.

When we turn to the other field of thought with which the name of
Thales is associated---namely, geometry---we again find evidence of
the Oriental influence. The science of geometry, Herodotus assures
us, was invented in Egypt. It was there an eminently practical science,
being applied, as the name literally suggests, to the measurement
of the earth's surface. Herodotus tells us that the Egyptians were
obliged to cultivate the science because the periodical inundations
washed away the boundary-lines between their farms. The primitive
geometer, then, was a surveyor. The Egyptian records, as now revealed
to us, show that the science had not been carried far in the land
of its birth. The Egyptian geometer was able to measure irregular
pieces of land only approximately. He never fully grasped the idea
of the perpendicular as the true index of measurement for the triangle,
but based his calculations upon measurements of the actual side of
that figure. Nevertheless, he had learned to square the circle with
a close approximation to the truth, and, in general, his measurement
sufficed for all his practical needs. Just how much of the geometrical
knowledge which added to the fame of Thales was borrowed directly
from the Egyptians, and how much he actually created we cannot be
sure. Nor is the question raised in disparagement of his genius. Receptivity
is the first prerequisite to progressive thinking, and that Thales
reached out after and imbibed portions of Oriental wisdom argues in
itself for the creative character of his genius. Whether borrower
of originator, however, Thales is credited with the expression of
the following geometrical truths:\ 

\begin{enumerate}
\item \begin{flushleft}That the circle is bisected by its diameter.\end{flushleft}
\item \begin{flushleft}That the angles at the base of an isosceles triangle
are equal.\end{flushleft}
\item \begin{flushleft}That when two straight lines cut each other the vertical
opposite angles are equal.\end{flushleft}
\item \begin{flushleft}That the angle in a semicircle is a right angle.\end{flushleft}
\item \begin{flushleft}That one side and one acute angle of a right-angle
triangle determine the other sides of the triangle.\end{flushleft}
\end{enumerate}
It was by the application of the last of these principles that Thales
is said to have performed the really notable feat of measuring the
distance of a ship from the shore, his method being precisely the
same in principle as that by which the guns are sighted on a modern
man-of-war. Another practical demonstration which Thales was credited
with making, and to which also his geometrical studies led him, was
the measurement of any tall object, such as a pyramid or building
or tree, by means of its shadow. The method, though simple enough,
was ingenious. It consisted merely in observing the moment of the
day when a perpendicular stick casts a shadow equal to its own length.
Obviously the tree or monument would also cast a shadow equal to its
own height at the same moment. It remains then but to measure the
length of this shadow to determine the height of the object. Such
feats as this evidence the practicality of the genius of Thales. They
suggest that Greek science, guided by imagination, was starting on
the high-road of observation. We are told that Thales conceived for
the first time the geometry of lines, and that this, indeed, constituted
his real advance upon the Egyptians. We are told also that he conceived
the eclipse of the sun as a purely natural phenomenon, and that herein
lay his advance upon the Chaldean point of view. But if this be true
Thales was greatly in advance of his time, for it will be recalled
that fully two hundred years later the Greeks under Nicias before
Syracuse were so disconcerted by the appearance of an eclipse, which
was interpreted as a direct omen and warning, that Nicias threw away
the last opportunity to rescue his army. Thucydides, it is true, in
recording this fact speaks disparagingly of the superstitious bent
of the mind of Nicias, but Thucydides also was a man far in advance
of his time.

All that we know of the psychology of Thales is summed up in the famous
maxim, {}``Know thyself,''\ a maxim which, taken in connection
with the proven receptivity of the philosopher's mind, suggests to
us a marvellously rounded personality.

The disciples or successors of Thales, Anaximander and Anaximenes,
were credited with advancing knowledge through the invention or introduction
of the sundial. We may be sure, however, that the gnomon, which is
the rudimentary sundial, had been known and used from remote periods
in the Orient, and the most that is probable is that Anaximander may
have elaborated some special design, possibly the bowl-shaped sundial,
through which the shadow of the gnomon would indicate the time. The
same philosopher is said to have made the first sketch of a geographical
map, but this again is a statement which modern researches have shown
to be fallacious, since a Babylonian attempt at depicting the geography
of the world is still preserved to us on a clay tablet. Anaximander
may, however, have been the first Greek to make an attempt of this
kind. Here again the influence of Babylonian science upon the germinating
Western thought is suggested.

It is said that Anaximander departed from Thales's conception of the
earth, and, it may be added, from the Babylonian conception also,
in that he conceived it as a cylinder, or rather as a truncated cone,
the upper end of which is the habitable portion. This conception is
perhaps the first of these guesses through which the Greek mind attempted
to explain the apparent fixity of the earth. To ask what supports
the earth in space is most natural, but the answer given by Anaximander,
like that more familiar Greek solution which transformed the cone,
or cylinder, into the giant Atlas, is but another illustration of
that substitution of unwarranted inference for scientific induction
which we have already so often pointed out as characteristic of the
primitive stages of thought.

Anaximander held at least one theory which, as vouched for by various
copyists and commentators, entitles him to be considered perhaps the
first teacher of the idea of organic evolution. According to this
idea, man developed from a fishlike ancestor, {}``growing up as sharks
do until able to help himself and then coming forth on dry land.''%
\footnote{Anaximander, as recorded by Plutarch, \textit{\emph{vol}}.\ VIII.
See Arthur Fairbanks' \emph{First Philosophers of Greece: an Edition
and Translation of the Remaining Fragments of the Pre-Socratic Philosophers,
together with a Translation of the more Important Accounts of their
Opinions Contained in the Early Epitomcs of their Works}, London,
1898. This highly scholarly and extremely useful book contains the
Greek text as well as translations.%
} The thought here expressed finds its germ, perhaps, in the Babylonian
conception that everything came forth from a chaos of waters. Yet
the fact that the thought of Anaximander has come down to posterity
through such various channels suggests that the Greek thinker had
got far enough away from the Oriental conception to make his view
seem to his contemporaries a novel and individual one. Indeed, nothing
we know of the Oriental line of thought conveys any suggestion of
the idea of transformation of species, whereas that idea is distinctly
formulated in the traditional views of Anaximander.


\chapter*{\raggedright VI. THE EARLY GREEK PHILOSOPHERS IN ITALY}

\addcontentsline{toc}{chapter}{VI. THE EARLY GREEK PHILOSOPHERS\\
IN ITALY}

\markboth{A HISTORY OF SCIENCE, BOOK I}{VI. GREEK PHILOSOPHERS IN
ITALY}

Diogenes Laertius tells a story about a youth who, clad in a purple
toga, entered the arena at the Olympian games and asked to compete
with the other youths in boxing. He was derisively denied admission,
presumably because he was beyond the legitimate age for juvenile contestants.
Nothing daunted, the youth entered the lists of men, and turned the
laugh on his critics by coming off victor. The youth who performed
this feat was named Pythagoras. He was the same man, if we may credit
the story, who afterwards migrated to Italy and became the founder
of the famous Crotonian School of Philosophy; the man who developed
the religion of the Orphic mysteries; who conceived the idea of the
music of the spheres; who promulgated the doctrine of metempsychosis;
who first, perhaps, of all men clearly conceived the notion that this
world on which we live is a ball which moves in space and which may
be habitable on every side.

A strange development that for a stripling pugilist. But we must not
forget that in the Greek world athletics held a peculiar place. The
chief winner of Olympian games gave his name to an epoch (the ensuing
Olympiad of four years), and was honored almost before all others
in the land. A sound mind in a sound body was the motto of the day.
To excel in feats of strength and dexterity was an accomplishment
that even a philosopher need not scorn. It will be recalled that \AE{}\AE{}schylus
distinguished himself at the battle of Marathon; that Thucydides,
the greatest of Greek historians, was a general in the Peloponnesian
War; that Xenophon, the pupil and biographer of Socrates, was chiefly
famed for having led the Ten Thousand in the memorable campaign of
Cyrus the Younger; that Plato himself was credited with having shown
great aptitude in early life as a wrestler. If, then, Pythagoras the
philosopher was really the Pythagoras who won the boxing contest,
we may suppose that in looking back upon this athletic feat from the
heights of his priesthood---for he came to be almost deified---he
regarded it not as an indiscretion of his youth, but as one of the
greatest achievements of his life. Not unlikely he recalled with pride
that he was credited with being no less an innovator in athletics
than in philosophy. At all events, tradition credits him with the
invention of {}``scientific'' boxing. Was it he, perhaps, who taught
the Greeks to strike a rising and swinging blow from the hip, as depicted
in the famous \textit{metopes} of the Parthenon? If so, the innovation
of Pythagoras was as little heeded in this regard in a subsequent
age as was his theory of the motion of the earth; for to strike a
swinging blow from the hip, rather than from the shoulder, is a trick
which the pugilist learned anew in our own day.

But enough of pugilism and of what, at best, is a doubtful tradition.
Our concern is with another {}``science''\ than that of the arena.
We must follow the purple-robed victor to Italy---if, indeed, we be
not over-credulous in accepting the tradition---and learn of triumphs
of a different kind that have placed the name of Pythagoras high on
the list of the fathers of Grecian thought. To Italy? Yes, to the
western limits of the Greek world. Here it was, beyond the confines
of actual Greek territory, that Hellenic thought found its second
home, its first home being, as we have seen, in Asia Minor. Pythagoras,
indeed, to whom we have just been introduced, was born on the island
of Samos, which lies near the coast of Asia Minor, but he probably
migrated at an early day to Crotona, in Italy. There he lived, taught,
and developed his philosophy until rather late in life, when, having
incurred the displeasure of his fellow-citizens, he suffered the not
unusual penalty of banishment.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S114}\end{center}

\noindent \begin{center}\noun{\small Pythagoras}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (From an old print.) }\end{center}
\end{figure}
Of the three other great Italic leaders of thought of the early period,
Xenophanes came rather late in life to Elea and founded the famous
Eleatic School, of which Parmenides became the most distinguished
ornament. These two were Ionians, and they lived in the sixth century
before our era. Empedocles, the Sicilian, was of Doric origin. He
lived about the middle of the fifth century B.C., at a time, therefore,
when Athens had attained a position of chief glory among the Greek
states; but there is no evidence that Empedocles ever visited that
city, though it was rumored that he returned to the Peloponnesus to
die. The other great Italic philosophers just named, living, as we
have seen, in the previous century, can scarcely have thought of Athens
as a centre of Greek thought. Indeed, the very fact that these men
lived in Italy made that peninsula, rather than the mother-land of
Greece, the centre of Hellenic influence. But all these men, it must
constantly be borne in mind, were Greeks by birth and language, fully
recognized as such in their own time and by posterity. Yet the fact
that they lived in a land which was at no time a part of the geographical
territory of Greece must not be forgotten. They, or their ancestors
of recent generations, had been pioneers among those venturesome colonists
who reached out into distant portions of the world, and made homes
for themselves in much the same spirit in which colonists from Europe
began to populate America some two thousand years later. In general,
colonists from the different parts of Greece localized themselves
somewhat definitely in their new homes; yet there must naturally have
been a good deal of commingling among the various families of pioneers,
and, to a certain extent, a mingling also with the earlier inhabitants
of the country. This racial mingling, combined with the well-known
vitalizing influence of the pioneer life, led, we may suppose, to
a more rapid and more varied development than occurred among the home-staying
Greeks. In proof of this, witness the remarkable schools of philosophy
which, as we have seen, were thus developed at the confines of the
Greek world, and which were presently to invade and, as it were, take
by storm the mother-country itself.

As to the personality of these pioneer philosophers of the West, our
knowledge is for the most part more or less traditional. What has
been said of Thales may be repeated, in the main, regarding Pythagoras,
Parmenides, and Empedocles. That they were real persons is not at
all in question, but much that is merely traditional has come to be
associated with their names. Pythagoras was the senior, and doubtless
his ideas may have influenced the others more or less, though each
is usually spoken of as the founder of an independent school. Much
confusion has all along existed, however, as to the precise ideas
which were to be ascribed to each of the leaders. Numberless commentators,
indeed, have endeavored to pick out from among the traditions of antiquity,
aided by such fragments of the writing of the philosophers as have
come down to us, the particular ideas that characterized each thinker,
and to weave these ideas into systems. But such efforts, notwithstanding
the mental energy that has been expended upon them, were, of necessity,
futile, since, in the first place, the ancient philosophers themselves
did not specialize and systematize their ideas according to modern
notions, and, in the second place, the records of their individual
teachings have been too scantily preserved to serve for the purpose
of classification. It is freely admitted that fable has woven an impenetrable
mesh of contradictions about the personalities of these ancient thinkers,
and it would be folly to hope that this same artificer had been less
busy with their beliefs and theories. When one reads that Pythagoras
advocated an exclusively vegetable diet, yet that he was the first
to train athletes on meat diet; that he sacrificed only inanimate
things, yet that he offered up a hundred oxen in honor of his great
discovery regarding the sides of a triangle, and such like inconsistencies
in the same biography, one gains a realizing sense of the extent to
which diverse traditions enter into the story as it has come down
to us. And yet we must reflect that most men change their opinions
in the course of a long lifetime, and that the antagonistic reports
may both be true.

True or false, these fables have an abiding interest, since they prove
the unique and extraordinary character of the personality about which
they are woven. The alleged witticisms of a Whistler, in our own day,
were doubtless, for the most part, quite unknown to Whistler himself,
yet they never would have been ascribed to him were they not akin
to witticisms that he did originate---were they not, in short, typical
expressions of his personality. And so of the heroes of the past.
{}``It is no ordinary man,''\ said George Henry Lewes, speaking
of Pythagoras, {}``whom fable exalts into the poetic region. Whenever
you find romantic or miraculous deeds attributed, be certain that
the hero was great enough to maintain the weight of the crown of this
fabulous glory.''%
\footnote{George Henry Lewes, \emph{A Biographical History of Philosophy from
its Origin in Greece down to the Present Day}, enlarged edition, New
York, 1888, p.\ 17.%
} We may not doubt, then, that Pythagoras, Parmenides, and Empedocles,
with whose names fable was so busy throughout antiquity, were men
of extraordinary personality. We are here chiefly concerned, however,
neither with the personality of the man nor yet with the precise doctrines
which each one of them taught. A knowledge of the latter would be
interesting were it attainable, but in the confused state of the reports
that have come down to us we cannot hope to be able to ascribe each
idea with precision to its proper source. At best we can merely outline,
even here not too precisely, the scientific doctrines which the Italic
philosophers as a whole seem to have advocated.

First and foremost, there is the doctrine that the earth is a sphere.
Pythagoras is said to have been the first advocate of this theory;
but, unfortunately, it is reported also that Parmenides was its author.
This rivalship for the discovery of an important truth we shall see
repeated over and over in more recent times. Could we know the whole
truth, it would perhaps appear that the idea of the sphericity of
the earth was originated long before the time of the Greek philosophers.
But it must be admitted that there is no record of any sort to give
tangible support to such an assumption. So far as we can ascertain,
no Egyptian or Babylonian astronomer ever grasped the wonderful conception
that the earth is round. That the Italic Greeks should have conceived
that idea was perhaps not so much because they were astronomers as
because they were practical geographers and geometers. Pythagoras,
as we have noted, was born at Samos, and, therefore, made a relatively
long sea voyage in passing to Italy. Now, as every one knows, the
most simple and tangible demonstration of the convexity of the earth's
surface is furnished by observation of an approaching ship at sea.
On a clear day a keen eye may discern the mast and sails rising gradually
above the horizon, to be followed in due course by the hull. Similarly,
on approaching the shore, high objects become visible before those
that lie nearer the water. It is at least a plausible supposition
that Pythagoras may have made such observations as these during the
voyage in question, and that therein may lie the germ of that wonderful
conception of the world as a sphere.

To what extent further proof, based on the fact that the earth's shadow
when the moon is eclipsed is always convex, may have been known to
Pythagoras we cannot say. There is no proof that any of the Italic
philosophers made extensive records of astronomical observations as
did the Egyptians and Babylonians; but we must constantly recall that
the writings of classical antiquity have been almost altogether destroyed.
The absence of astronomical records is, therefore, no proof that such
records never existed. Pythagoras, it should be said, is reported
to have travelled in Egypt, and he must there have gained an inkling
of astronomical methods. Indeed, he speaks of himself specifically,
in a letter quoted by Diogenes, as one who is accustomed to study
astronomy. Yet a later sentence of the letter, which asserts that
the philosopher is not always occupied about speculations of his own
fancy, suggesting, as it does, the dreamer rather than the observer,
gives us probably a truer glimpse into the philosopher's mind. There
is, indeed, reason to suppose that the doctrine of the sphericity
of the earth appealed to Pythagoras chiefly because it accorded with
his conception that the sphere is the most perfect solid, just as
the circle is the most perfect plane surface. Be that as it may, the
fact remains that we have here, as far as we can trace its origin,
the first expression of the scientific theory that the earth is round.
Had the Italic philosophers accomplished nothing more than this, their
accomplishment would none the less mark an epoch in the progress of
thought.

That Pythagoras was an observer of the heavens is further evidenced
by the statement made by Diogenes, on the authority of Parmenides,
that Pythagoras was the first person who discovered or asserted the
identity of Hesperus and Lucifer---that is to say, of the morning
and the evening star. This was really a remarkable discovery, and
one that was no doubt instrumental later on in determining that theory
of the mechanics of the heavens which we shall see elaborated presently.
To have made such a discovery argues again for the practicality of
the mind of Pythagoras. His, indeed, would seem to have been a mind
in which practical common-sense was strangely blended with the capacity
for wide and imaginative generalization. As further evidence of his
practicality, it is asserted that he was the first person who introduced
measures and weights among the Greeks, this assertion being made on
the authority of Aristoxenus. It will be observed that he is said
to have introduced, not to have invented, weights and measures, a
statement which suggests a knowledge on the part of the Greeks that
weights and measures were previously employed in Egypt and Babylonia.

The mind that could conceive the world as a sphere and that interested
itself in weights and measures was, obviously, a mind of the visualizing
type. It is characteristic of this type of mind to be interested in
the tangibilities of geometry, hence it is not surprising to be told
that Pythagoras {}``carried that science to perfection.'' The most
famous discovery of Pythagoras in this field was that the square of
the hypotenuse of a right-angled triangle is equal to the squares
of the other sides of the triangle. We have already noted the fable
that his enthusiasm over this discovery led him to sacrifice a hecatomb.
Doubtless the story is apocryphal, but doubtless, also, it expresses
the truth as to the fervid joy with which the philosopher must have
contemplated the results of his creative imagination.

No line alleged to have been written by Pythagoras has come down to
us. We are told that he refrained from publishing his doctrines, except
by word of mouth. {}``The Lucanians and the Peucetians, and the Messapians
and the Romans,''\ we are assured, {}``flocked around him, coming
with eagerness to hear his discourses; no fewer than six hundred came
to him every night; and if any one of them had ever been permitted
to see the master, they wrote of it to their friends as if they had
gained some great advantage.'' Nevertheless, we are assured that
until the time of Philolaus no doctrines of Pythagoras were ever published,
to which statement it is added that {}``when the three celebrated
books were published, Plato wrote to have them purchased for him for
a hundred minas.''%
\footnote{Diogenes Laertius, \emph{The Lives and Opinions of Eminent Philosophers},
C.\ D.\ Yonge's translation, London, 1853, VIII., p.\ 153.%
} But if such books existed, they are lost to the modern world, and
we are obliged to accept the assertions of relatively late writers
as to the theories of the great Crotonian.

Perhaps we cannot do better than quote at length from an important
summary of the remaining doctrines of Pythagoras, which Diogenes himself
quoted from the work of a predecessor.%
\footnote{Alexander, \emph{Successions of Philosophers}.%
} Despite its somewhat inchoate character, this summary is a most remarkable
one, as a brief analysis of its contents will show. It should be explained
that Alexander (whose work is now lost)\ is said to have found these
dogmas set down in the commentaries of Pythagoras. If this assertion
be accepted, we are brought one step nearer the philosopher himself.
The summary is as follows:\ 

\begin{quotation}
{}``That the monad was the beginning of everything. From the monad
proceeds an indefinite duad, which is subordinate to the monad as
to its cause. That from the monad and the indefinite duad proceed
numbers. And from numbers signs. And from these last, lines of which
plane figures consist. And from plane figures are derived solid bodies.
And from solid bodies sensible bodies, of which last there are four
elements---fire, water, earth, and air. And that the world, which
is indued with life and intellect, and which is of a spherical figure,
having the earth, which is also spherical, and inhabited all over
in its centre,%
\footnote{{}``All over its centre.'' Presumably this is intended to refer
to the entire equatorial region.%
} results from a combination of these elements, and derives its motion
from them; and also that there are antipodes, and that what is below,
as respects us, is above in respect of them.

{}``He also taught that light and darkness, and cold and heat, and
dryness and moisture, were equally divided in the world; and that
while heat was predominant it was summer; while cold had the mastery,
it was winter; when dryness prevailed, it was spring; and when moisture
preponderated, winter. And while all these qualities were on a level,
then was the loveliest season of the year; of which the flourishing
spring was the wholesome period, and the season of autumn the most
pernicious one. Of the day, he said that the flourishing period was
the morning, and the fading one the evening; on which account that
also was the least healthy time.

{}``Another of his theories was that the air around the earth was
immovable and pregnant with disease, and that everything in it was
mortal; but that the upper air was in perpetual motion, and pure and
salubrious, and that everything in that was immortal, and on that
account divine. And that the sun and the moon and the stars were all
gods; for in them the warm principle predominates which is the cause
of life. And that the moon derives its light from the sun. And that
there is a relationship between men and the gods, because men partake
of the divine principle; on which account, also, God exercises his
providence for our advantage. Also, that Fate is the cause of the
arrangement of the world both generally and particularly. Moreover,
that a ray from the sun penetrated both the cold \textit{\emph{\ae{}ther}}
and the \textit{\emph{dense}} \textit{\emph{\ae{}ther}}; and they
call the air the cold \textit{\emph{\ae{}ther}}, and the sea and
moisture they call the \textit{\emph{dense}} \textit{\emph{\ae{}ther}}.
And this ray descends into the depths, and in this way vivifies everything.
And everything which partakes of the principle of heat lives, on which
account, also, plants are animated beings; but that all living things
have not necessarily souls. And that the soul is a something torn
off from the \textit{\emph{\ae{}ther}}, both warm and cold, from
its partaking of the cold \textit{\emph{\ae{}ther}}. And that the
soul is something different from life. Also, that it is immortal,
because that from which it has been detached is immortal.

{}``Also, that animals are born from one another by seeds, and that
it is impossible for there to be any spontaneous production by the
earth. And that seed is a drop from the brain which contains in itself
a warm vapor; and that when this is applied to the womb it transmits
virtue and moisture and blood from the brain, from which flesh and
sinews and bones and hair and the whole body are produced. And from
the vapor is produced the soul, and also sensation. And that the infant
first becomes a solid body at the end of forty days; but, according
to the principles of harmony, it is not perfect till seven, or perhaps
nine, or at most ten months, and then it is brought forth. And that
it contains in itself all the principles of life, which are all connected
together, and by their union and combination form a harmonious whole,
each of them developing itself at the appointed time.

{}``The senses in general, and especially the sight, are a vapor
of excessive warmth, and on this account a man is said to see through
air and through water. For the hot principle is opposed by the cold
one; since, if the vapor in the eyes were cold, it would have the
same temperature as the air, and so would be dissipated. As it is,
in some passages he calls the eyes the gates of the sun; and he speaks
in a similar manner of hearing and of the other senses.

{}``He also says that the soul of man is divided into three parts:
into intuition and reason and mind, and that the first and last divisions
are found also in other animals, but that the middle one, reason,
is only found in man. And that the chief abode of the soul is in those
parts of the body which are between the heart and the brain. And that
that portion of it which is in the heart is the mind; but that deliberation
and reason reside in the brain.

{}``Moreover, that the senses are drops from them; and that the reasoning
sense is immortal, but the others are mortal. And that the soul is
nourished by the blood; and that reasons are the winds of the soul.
That it is invisible, and so are its reasons, since the \textit{\emph{\ae{}ther}}
itself is invisible. That the links of the soul are the veins and
the arteries and the nerves. But that when it is vigorous, and is
by itself in a quiescent state, then its links are words and actions.
That when it is cast forth upon the earth it wanders about, resembling
the body. Moreover, that Mercury is the steward of the souls, and
that on this account he has the name of Conductor, and Commercial,
and Infernal, since it is he who conducts the souls from their bodies,
and from earth and sea; and that he conducts the pure souls to the
highest region, and that he does not allow the impure ones to approach
them, nor to come near one another, but commits them to be bound in
indissoluble fetters by the Furies. The Pythagoreans also assert that
the whole air is full of souls, and that these are those which are
accounted d\ae{}mons and heroes. Also, that it is by them that dreams
are sent among men, and also the tokens of disease and health; these
last, too, being sent not only to men, but to sheep also, and other
cattle. Also that it is they who are concerned with purifications
and \textit{\emph{expiations}} and all kinds of divination and oracular
predictions, and things of that kind.''%
\footnote{Laertius, \emph{op.\ cit}., \textit{\emph{pp}}.\ 348-351.%
}
\end{quotation}
{}

A brief consideration of this summary of the doctrines of Pythagoras
will show that it at least outlines a most extraordinary variety of
scientific ideas.\ (1)\ There is suggested a theory of monads and
the conception of the development from simple to more complex bodies,
passing through the stages of lines, plain figures, and solids to
sensible bodies.\ (2)\ The doctrine of the four elements---fire,
water, earth, and air---as the basis of all organisms is put forward.\ (3)\ The
idea, not merely of the sphericity of the earth, but an explicit conception
of the antipodes, is expressed.\ (4)\ A conception of the sanitary
influence of the air is clearly expressed.\ (5)\ An idea of the
problems of generation and heredity is shown, together with a distinct
disavowal of the doctrine of spontaneous generation---\ a doctrine
which, it may be added, remained in vogue, nevertheless, for some
twenty-four hundred years after the time of Pythagoras. (6)\ A remarkable
analysis of mind is made, and a distinction between animal minds and
the human mind is based on this analysis. The physiological doctrine
that the heart is the organ of one department of mind is offset by
the clear statement that the remaining factors of mind reside in the
brain. This early recognition of brain as the organ of mind must not
be forgotten in our later studies. It should be recalled, however,
that a Crotonian physician, Alemaean, a younger contemporary of Pythagoras,
is also credited with the same theory.\ (7)\ A knowledge of anatomy
is at least vaguely foreshadowed in the assertion that veins, arteries,
and nerves are the links of the soul. In this connection it should
be recalled that Pythagoras was a practical physician.

As against these scientific doctrines, however, some of them being
at least remarkable guesses at the truth, attention must be called
to the concluding paragraph of our quotation, in which the old familiar
d\ae{}monology is outlined, quite after the Oriental fashion. We
shall have occasion to say more as to this phase of the subject later
on. Meantime, before leaving Pythagoras, let us note that his practical
studies of humanity led him to assert the doctrine that {}``the property
of friends is common, and that friendship is equality.'' His disciples,
we are told, used to put all their possessions together in one store
and use them in common. Here, then, seemingly, is the doctrine of
communism put to the test of experiment at this early day. If it seem
that reference to this carries us beyond the bounds of science, it
may be replied that questions such as this will not lie beyond the
bounds of the science of the near future.


\section*{\raggedright XENOPHANES AND PARMENIDES}

\addcontentsline{toc}{section}{XENOPHANES AND PARMENIDES}

There is a whimsical tale about Pythagoras, according to which the
philosopher was wont to declare that in an earlier state he had visited
Hades, and had there seen Homer and Hesiod tortured because of the
absurd things they had said about the gods. Apocryphal or otherwise,
the tale suggests that Pythagoras was an agnostic as regards the current
Greek religion of his time. The same thing is perhaps true of most
of the great thinkers of this earliest period. But one among them
was remembered in later times as having had a peculiar aversion to
the anthropomorphic conceptions of his fellows. This was Xenophanes,
who was born at Colophon probably about the year 580 B.C., and who,
after a life of wandering, settled finally in Italy and became the
founder of the so-called Eleatic School.

A few fragments of the philosophical poem in which Xenophanes expressed
his views have come down to us, and these fragments include a tolerably
definite avowal of his faith. {}``God is one supreme among gods and
men, and not like mortals in body or in mind,''\ says Xenophanes.
Again he asserts that {}``mortals suppose that the gods are born
(as they themselves are), that they wear man's clothing and have human
voice and body; but,''\ he continues, {}``if cattle or lions had
hands so as to paint with their hands and produce works of art as
men do, they would paint their gods and give them bodies in form like
their own---horses like horses, cattle like cattle.'' Elsewhere he
says, with great acumen: {}``There has not been a man, nor will there
be, who knows distinctly what I say about the gods or in regard to
all things. For even if one chance for the most part to say what is
true, still he would not know; but every one thinks that he knows.''%
\footnote{Arthur Fairbanks, \emph{The First Philosophers of Greece,} London,
1898, \textit{\emph{pp}}.\ 67-717.%
}

In the same spirit Xenophanes speaks of the battles of Titans, of
giants, and of centaurs as {}``fictions of former ages.'' All this
tells of the questioning spirit which distinguishes the scientific
investigator. Precisely whither this spirit led him we do not know,
but the writers of a later time have preserved a tradition regarding
a belief of Xenophanes that perhaps entitles him to be considered
the father of geology. Thus Hippolytus records that Xenophanes studied
the fossils to be found in quarries, and drew from their observation
remarkable conclusions. His words are as follows: {}``Xenophanes
believes that once the earth was mingled with the sea, but in the
course of time it became freed from moisture; and his proofs are such
as these: that shells are found in the midst of the land and among
the mountains, that in the quarries of Syracuse the imprints of a
fish and of seals had been found, and in \textit{\emph{Paros}} the
imprint of an anchovy at some depth in the stone, and in Melite shallow
impressions of all sorts of sea products. He says that these imprints
were made when everything long ago was covered with mud, and then
the imprint dried in the mud. Further, he says that all men will be
destroyed when the earth sinks into the sea and becomes mud, and that
the race will begin anew from the beginning; and this transformation
takes place for all worlds.''%
\footnote{\emph{Ibid}., p.\ 838.%
} Here, then, we see this earliest of paleontologists studying the
fossil-bearing strata of the earth, and drawing from his observations
a marvellously scientific induction. Almost two thousand years later
another famous citizen of \textit{\emph{Italy}}\emph{,} \textit{\emph{Leonardo}}
\emph{}\textit{\emph{da}} Vinci, was independently to think out similar
conclusions from like observations. But not until the nineteenth century
of our era, some twenty-four hundred years after the time of Xenophanes,
was the old Greek's doctrine to be accepted by the scientific world.
The ideas of Xenophanes were known to his contemporaries and, as we
see, quoted for a few centuries by his successors, then they were
ignored or quite forgotten; and if any philosopher of an ensuing age
before the time of Leonardo championed a like rational explanation
of the fossils, we have no record of the fact. The geological doctrine
of Xenophanes, then, must be listed among those remarkable Greek anticipations
of nineteenth-century science which suffered almost total eclipse
in the intervening centuries.

Among the pupils of Xenophanes was Parmenides, the thinker who was
destined to carry on the work of his master along the same scientific
lines, though at the same time mingling his scientific conceptions
with the mysticism of the poet. We have already had occasion to mention
that Parmenides championed the idea that the earth is round; noting
also that doubts exist as to whether he or Pythagoras originated this
doctrine. No explicit answer to this question can possibly be hoped
for. It seems clear, however, that for a long time the Italic School,
to which both these philosophers belonged, had a monopoly of the belief
in question. Parmenides, like Pythagoras, is credited with having
believed in the motion of the earth, though the evidence furnished
by the writings of the philosopher himself is not as demonstrative
as one could wish. Unfortunately, the copyists of a later age were
more concerned with metaphysical speculations than with more tangible
things. But as far as the fragmentary references to the ideas of Parmenides
may be accepted, they do not support the idea of the earth's motion.
Indeed, Parmenides is made to say explicitly, in preserved fragments,
that {}``the world is immovable, limited, and spheroidal in form.''%
\footnote{\emph{Ibid}., p.\ 109.%
}

Nevertheless, some modern interpreters have found an opposite meaning
in Parmenides. Thus Ritter interprets him as supposing {}``that the
earth is in the centre spherical, and maintained in rotary motion
by its equiponderance; around it lie certain rings, the highest composed
of the rare element fire, the next lower a compound of light and darkness,
and lowest of all one wholly of night, which probably indicated to
his mind the surface of the earth, the centre of which again he probably
considered to be fire.''%
\footnote{Heinrich Ritter, \emph{The History of Ancient Philosophy}, translated
from the German by A.\ J.\ W.\ Morrison, 4 \textit{\emph{vols}}.,
London, 1838, \textit{\emph{vol}}.\ I., p.\ 463.%
} But this, like too many interpretations of ancient thought, appears
to read into the fragments ideas which the words themselves do not
warrant. There seems no reason to doubt, however, that Parmenides
actually held the doctrine of the earth's sphericity. Another glimpse
of his astronomical doctrines is furnished us by a fragment which
tells us that he conceived the morning and the evening stars to be
the same, a doctrine which, as we have seen, was ascribed also to
Pythagoras. Indeed, we may repeat that it is quite impossible to distinguish
between the astronomical doctrines of these two philosophers.

The poem of Parmenides in which the cosmogonic speculations occur
treats also of the origin of man. The author seems to have had a clear
conception that intelligence depends on bodily organism, and that
the more elaborately developed the organism the higher the intelligence.
But in the interpretation of this thought we are hampered by the characteristic
vagueness of expression, which may best be evidenced by putting before
the reader two English translations of the same stanza. Here is Ritter's
rendering, as made into English by his translator, Morrison:\ 

\begin{verse}
{}``For exactly as each has the state of his limbs many-jointed,\\
So invariably stands it with men in their mind and their reason;\\
For the system of limbs is that which thinketh in mankind\\
Alike in all and in each: for thought is the fulness.''%
\footnote{\emph{Ibid}., p.\ 465.%
}
\end{verse}
{}

The same stanza is given thus by George Henry Lewes:\ 

\begin{verse}
{}``Such as to each man is the nature of his many-jointed limbs,\\
Such also is the intelligence of each man; for it is \\
The nature of limbs (organization)\ which thinketh in men, \\
Both in one and in all; for the highest degree of organization gives
the highest degree of thought.''%
\footnote{George Henry Lewes, \emph{op.\ cit}., p.\ 81.%
}
\end{verse}
{}

Here it will be observed that there is virtual agreement between the
translators except as to the last clause, but that clause is most
essential. The Greek phrase is \emph{$\tau $o $\gamma $$\alpha $$\rho $
$\pi $$\lambda $$\varepsilon $o$\nu $ $\varepsilon $$\sigma $$\tau $$\iota $
$\nu $oc$\mu $$\alpha $}. Ritter, it will be observed, renders
this, {}``for thought is the fulness.'' Lewes paraphrases it, {}``for
the highest degree of organization gives the highest degree of thought.''
The difference is intentional, since Lewes himself criticises the
translation of Ritter. Ritter's translation is certainly the more
literal, but the fact that such diversity is possible suggests one
of the chief elements of uncertainty that hamper our interpretation
of the thought of antiquity. Unfortunately, the mind of the commentator
has usually been directed towards such subtleties, rather than towards
the expression of precise knowledge. Hence it is that the philosophers
of Greece are usually thought of as mere dreamers, and that their
true status as scientific discoverers is so often overlooked. With
these intangibilities we have no present concern beyond this bare
mention; for us it suffices to gain as clear an idea as we may of
the really scientific conceptions of these thinkers, leaving the subtleties
of their deductive reasoning for the most part untouched.


\section*{\raggedright EMPEDOCLES}

\addcontentsline{toc}{section}{EMPEDOCLES}

The latest of the important pre-Socratic philosophers of the Italic
school was Empedocles, who was born about 494 B.C.\ and lived to
the age of sixty. These dates make Empedocles strictly contemporary
with Anaxagoras, a fact which we shall do well to bear in mind when
we come to consider the latter's philosophy in the succeeding chapter.
Like Pythagoras, Empedocles is an imposing figure. Indeed, there is
much of similarity between the personalities, as between the doctrines,
of the two men. Empedocles, like Pythagoras, was a physician; like
him also he was the founder of a cult. As statesman, prophet, physicist,
physician, reformer, and poet he showed a versatility that, coupled
with profundity, marks the highest genius. In point of versatility
we shall perhaps hardly find his equal at a later day---unless, indeed,
an exception be made of Eratosthenes. The myths that have grown about
the name of Empedocles show that he was a remarkable personality.
He is said to have been an awe-inspiring figure, clothing himself
in Oriental splendor and moving among mankind as a superior being.
Tradition has it that he threw himself into the crater of a volcano
that his otherwise unexplained disappearance might lead his disciples
to believe that he had been miraculously translated; but tradition
goes on to say that one of the brazen slippers of the philosopher
was thrown up by the volcano, thus revealing his subterfuge. Another
tradition of far more credible aspect asserts that Empedocles retreated
from Italy, returning to the home of his fathers in Peloponnesus to
die there obscurely. It seems odd that the facts regarding the death
of so great a man, at so comparatively late a period, should be obscure;
but this, perhaps, is in keeping with the personality of the man himself.
His disciples would hesitate to ascribe a merely natural death to
so inspired a prophet.

Empedocles appears to have been at once an observer and a dreamer.
He is credited with noting that the pressure of air will sustain the
weight of water in an inverted tube; with divining, without the possibility
of proof, that light has actual motion in space; and with asserting
that centrifugal motion must keep the heavens from falling. He is
credited with a great sanitary feat in the draining of a marsh, and
his knowledge of medicine was held to be supernatural. Fortunately,
some fragments of the writings of Empedocles have come down to us,
enabling us to judge at first hand as to part of his doctrines; while
still more is known through the references made to him by Plato, Aristotle,
and other commentators. Empedocles was a poet whose verses stood the
test of criticism. In this regard he is in a like position with Parmenides;
but in neither case are the preserved fragments sufficient to enable
us fully to estimate their author's scientific attainments. Philosophical
writings are obscure enough at the best, and they perforce become
doubly so when expressed in verse. Yet there are certain passages
of Empedocles that are unequivocal and full of interest. Perhaps the
most important conception which the works of Empedocles reveal to
us is the denial of anthropomorphism as applied to deity. We have
seen how early the anthropomorphic conception was developed and how
closely it was all along clung to; to shake the mind free from it
then was a remarkable feat, in accomplishing which Empedocles took
a long step in the direction of rationalism. His conception is paralleled
by that of another physician, Alcm\ae{}on, of Proton, who contended
that man's ideas of the gods amounted to mere suppositions at the
very most. A rationalistic or sceptical tendency has been the accompaniment
of medical training in all ages.

The words in which Empedocles expresses his conception of deity have
been preserved and are well worth quoting: {}``It is not impossible,''\ he
says, {}``to draw near (to god)\ even with the eyes or to take hold
of him with our hands, which in truth is the best highway of persuasion
in the mind of man; for he has no human head fitted to a body, nor
do two shoots branch out from the trunk, nor has he feet, nor swift
legs, nor hairy parts, but he is sacred and ineffable mind alone,
darting through the whole world with swift thoughts.''%
\footnote{Fairbanks, \emph{op.\ cit.}, p.\ 201.%
}

How far Empedocles carried his denial of anthropomorphism is illustrated
by a reference of Aristotle, who asserts {}``that Empedocles regards
god as most lacking in the power of perception; for he alone does
not know one of the elements, Strife (hence), of perishable things.''
It is difficult to avoid the feeling that Empedocles here approaches
the modern philosophical conception that God, however postulated as
immutable, must also be postulated as unconscious, since intelligence,
as we know it, is dependent upon the \textit{\emph{transmutations}}
of matter. But to urge this thought would be to yield to that philosophizing
tendency which has been the bane of interpretation as applied to the
ancient thinkers.

Considering for a moment the more tangible accomplishments of Empedocles,
we find it alleged that one of his {}``miracles'' consisted of the
preservation of a dead body without putrefaction for some weeks after
death. We may assume from this that he had gained in some way a knowledge
of embalming. As he was notoriously fond of experiment, and as the
body in question (assuming for the moment the authenticity of the
legend)\ must have been preserved without disfigurement, it is conceivable
even that he had hit upon the idea of injecting the arteries. This,
of course, is pure conjecture; yet it finds a certain warrant, both
in the fact that the words of Pythagoras lead us to believe that the
arteries were known and studied, and in the fact that Empedocles'\ own
words reveal him also as a student of the vascular system. Thus Plutarch
cites Empedocles as believing {}``that the ruling part is not in
the head or in the breast, but in the blood; wherefore in whatever
part of the body the more of this is spread in that part men excel.''%
\footnote{\emph{Ibid}., P.\ 234.%
} And Empedocles'\ own words, as preserved by Stob\ae{}us, assert
{}``(the heart)\ lies in seas of blood which dart in opposite directions,
and there most of all intelligence centres for men; for blood about
the heart is intelligence in the case of man.'' All this implies
a really remarkable appreciation of the dependence of vital activities
upon the blood.

This correct physiological conception, however, was by no means the
most remarkable of the ideas to which Empedocles was led by his anatomical
studies. His greatest accomplishment was to have conceived and clearly
expressed an idea which the modern evolutionist connotes when he speaks
of homologous parts---an idea which found a famous modern expositor
in Goethe, as we shall see when we come to deal with eighteenth-century
science. Empedocles expresses the idea in these words: {}``Hair,
and leaves, and thick feathers of birds, are the same thing in origin,
and reptile scales too on strong limbs. But on hedgehogs sharp-pointed
hair bristles on their backs.''%
\footnote{\emph{Ibid}., p.\ 189.%
} That the idea of transmutation of parts, as well as of mere homology,
was in mind is evidenced by a very remarkable sentence in which Aristotle
asserts, {}``Empedocles says that fingernails rise from sinew from
hardening.'' Nor is this quite all, for surely we find the germ of
the Lamarckian conception of evolution through the transmission of
acquired characters in the assertion that {}``many characteristics
appear in animals because it happened to be thus in their birth, as
that they have such a spine because they happen to be descended from
one that bent itself backward.''%
\footnote{\emph{Ibid}., P.\ 220.%
} Aristotle, in quoting this remark, asserts, with the dogmatism which
characterizes the philosophical commentators of every age, that {}``Empedocles
is wrong,''\ in making this assertion; but Lamarck, who lived twenty-three
hundred years after Empedocles, is famous in the history of the doctrine
of evolution for elaborating this very idea.

It is fair to add, however, that the dreamings of Empedocles regarding
the origin of living organisms led him to some conceptions that were
much less luminous. On occasion, Empedocles the poet got the better
of Empedocles the scientist, and we are presented with a conception
of creation as grotesque as that which delighted the readers of \emph{Paradise
Lost} at a later day. Empedocles assures us that {}``many heads grow
up without necks, and arms were wandering about, necks bereft of shoulders,
and eyes roamed about alone with no foreheads.''%
\footnote{\emph{Ibid}., p.\ 189.%
} This chaotic condition, so the poet dreamed, led to the union of
many incongruous parts, producing {}``creatures with double faces,
offspring of oxen with human faces, and children of men with oxen
heads.'' But out of this chaos came, finally, we are led to infer,
a harmonious aggregation of parts, producing ultimately the perfected
organisms that we see. Unfortunately the preserved portions of the
writings of Empedocles do not enlighten us as to the precise way in
which final evolution was supposed to be effected; although the idea
of endless experimentation until natural selection resulted in survival
of the fittest seems not far afield from certain of the poetical assertions.
Thus: {}``As divinity was mingled yet more with divinity, these things
(the various members)\ kept coming together in whatever way each
might chance.'' Again: {}``At one time all the limbs which form
the body united into one by love grew vigorously in the prime of life;
but yet at another time, separated by evil Strife, they wander each
in different directions along the breakers of the sea of life. Just
so is it with plants, and with fishes dwelling in watery halls, and
beasts whose lair is in the mountains, and birds borne on wings.''%
\footnote{\emph{Ibid}., p.\ 191.%
}

All this is poetry rather than science, yet such imaginings could
come only to one who was groping towards what we moderns should term
an evolutionary conception of the origins of organic life; and however
grotesque some of these expressions may appear, it must be admitted
that the morphological ideas of Empedocles, as above quoted, give
the Sicilian philosopher a secure place among the anticipators of
the modern evolutionist.


\chapter*{\raggedright VII. GREEK SCIENCE IN THE EARLY ATTIC PERIOD}

\addcontentsline{toc}{chapter}{VII. GREEK SCIENCE IN THE EARLY\\
ATTIC PERIOD}

\markboth{A HISTORY OF SCIENCE, BOOK I}{VII. THE EARLY ATTIC PERIOD}

We have travelled rather far in our study of Greek science, and yet
we have not until now come to Greece itself. And even now, the men
whose names we are to consider were, for the most part, born in outlying
portions of the empire; they differed from the others we have considered
only in the fact that they were drawn presently to the capital. The
change is due to a most interesting sequence of historical events.
In the day when Thales and his immediate successors taught in Miletus,
when the great men of the Italic school were in their prime, there
was no single undisputed Centre of Greek influence. The Greeks were
a disorganized company of petty nations, welded together chiefly by
unity of speech; but now, early in the fifth century B.C., occurred
that famous attack upon the Western world by the Persians under Darius
and his son and successor Xerxes. A few months of battling determined
the fate of the Western world. The \textit{\emph{Orientals}} were
hurled back; the glorious memories of Marathon, Salamis, and Plataea
stimulated the patriotism and enthusiasm of all children of the Greek
race. The Greeks, for the first time, occupied the centre of the historical
stage; for the brief interval of about half a century the different
Grecian principalities lived together in relative harmony. One city
was recognized as the metropolis of the loosely bound empire; one
city became the home of culture and the Mecca towards which all eyes
turned; that city, of course, was Athens. For a brief time all roads
led to Athens, as, at a later date, they all led to Rome. The waterways
which alone bound the widely scattered parts of Hellas into a united
whole led out from Athens and back to Athens, as the spokes of a wheel
to its hub. Athens was the commercial centre, and, largely for that
reason, it became the centre of culture and intellectual influence
also. The wise men from the colonies visited the metropolis, and the
wise Athenians went out to the colonies. Whoever aspired to become
a leader in politics, in art, in literature, or in philosophy, made
his way to the capital, and so, with almost bewildering suddenness,
there blossomed the civilization of the age of Pericles; the civilization
which produced \AE{}schylus, Sophocles, Euripides, Herodotus, and
Thucydides; the civilization which made possible the building of the
Parthenon.


\section*{\raggedright ANAXAGORAS}

\addcontentsline{toc}{section}{ANAXAGORAS}

Sometime during the early part of this golden age there came to Athens
a middle-aged man from Clazomen\ae{}, who, from our present stand-point,
was a more interesting personality than perhaps any other in the great
galaxy of remarkable men assembled there. The name of this new-comer
was Anaxagoras. It was said in after-time, we know not with what degree
of truth, that he had been a pupil of Anaximenes. If so, he was a
pupil who departed far from the teachings of his master. What we know
for certain is that Anaxagoras was a truly original thinker, and that
he became a close friend---in a sense the teacher---of Pericles and
of Euripides. Just how long he remained at Athens is not certain;
but the time came when he had made himself in some way objectionable
to the Athenian populace through his teachings. Filled with the spirit
of the investigator, he could not accept the current conceptions as
to the gods. He was a sceptic, an innovator. Such men are never welcome;
they are the chief factors in the progress of thought, but they must
look always to posterity for recognition of their worth; from their
contemporaries they receive, not thanks, but persecution. Sometimes
this persecution takes one form, sometimes another; to the credit
of the Greeks be it said, that with them it usually led to nothing
more severe than banishment. In the case of Anaxagoras, it is alleged
that the sentence pronounced was death; but that, thanks to the influence
of Pericles, this sentence was commuted to banishment. In any event,
the aged philosopher was sent away from the city of his adoption.
He retired to Lampsacus. {}``It is not I that have lost the Athenians,''\ he
said; {}``it is the Athenians that have lost me.''

The exact position which Anaxagoras had among his contemporaries,
and his exact place in the development of philosophy, have always
been somewhat in dispute. It is not known, of a certainty, that he
even held an open school at Athens. Ritter thinks it doubtful that
he did. It was his fate to be misunderstood, or underestimated, by
Aristotle; that in itself would have sufficed greatly to dim his fame---might,
indeed, have led to his almost entire neglect had he not been a truly
remarkable thinker. With most of the questions that have exercised
the commentators we have but scant concern. Following Aristotle, most
historians of philosophy have been metaphysicians; they have concerned
themselves far less with what the ancient thinkers really knew than
with what they thought. A chance using of a verbal quibble, an esoteric
phrase, the expression of a vague mysticism---these would suffice
to call forth reams of exposition. It has been the favorite pastime
of historians to weave their own anachronistic theories upon the scanty
woof of the half-remembered thoughts of the ancient philosophers.
To make such cloth of the imagination as this is an alluring pastime,
but one that must not divert us here. Our point of view reverses that
of the philosophers. We are chiefly concerned, not with some vague
saying of Anaxagoras, but with what he really knew regarding the phenomena
of nature; with what he observed, and with the comprehensible deductions
that he derived from his observations. In attempting to answer these
inquiries, we are obliged, in part, to take our evidence at second-hand;
but, fortunately, some fragments of writings of Anaxagoras have come
down to us. We are told that he wrote only a single book. It was said
even (by Diogenes)\ that he was the first man that ever wrote a work
in prose. The latter statement would not bear too close an examination,
yet it is true that no extensive prose compositions of an earlier
day than this have been preserved, though numerous others are known
by their fragments. Herodotus, {}``the father of prose,''\ was
a slightly younger contemporary of the Clazomen\ae{}an philosopher;
not unlikely the two men may have met at Athens.

Notwithstanding the loss of the greater part of the writings of Anaxagoras,
however, a tolerably precise account of his scientific doctrines is
accessible. Diogenes Laertius expresses some of them in very clear
and precise terms. We have already pointed out the uncertainty that
attaches to such evidence as this, but it is as valid for Anaxagoras
as for another. If we reject such evidence, we shall often have almost
nothing left; in accepting it we may at least feel certain that we
are viewing the thinker as his contemporaries and immediate successors
viewed him. Following Diogenes, then, we shall find some remarkable
scientific opinions ascribed to Anaxagoras. {}``He asserted,''\ we
are told, {}``that the sun was a mass of burning iron, greater than
Peloponnesus, and that the moon contained houses and also hills and
ravines.'' In corroboration of this, Plato represents him as having
conjectured the right explanation of the moon's light, and of the
solar and lunar eclipses. He had other astronomical theories that
were more fanciful; thus {}``he said that the stars originally moved
about in irregular confusion, so that at first the pole-star, which
is continually visible, always appeared in the zenith, but that afterwards
it acquired a certain declination, and that the Milky Way was a reflection
of the light of the sun when the stars did not appear. The comets
he considered to be a concourse of planets emitting rays, and the
shooting-stars he thought were sparks, as it were, leaping from the
firmament.''

Much of this is far enough from the truth, as we now know it, yet
all of it shows an earnest endeavor to explain the observed phenomena
of the heavens on rational principles. To have predicated the sun
as a great molten mass of iron was indeed a wonderful anticipation
of the results of the modern spectroscope. Nor can it be said that
this hypothesis of Anaxagoras was a purely visionary guess. It was
in all probability a scientific deduction from the observed character
of meteoric stones. Reference has already been made to the alleged
prediction of the fall of the famous meteor at \AE{}gespotomi by
Anaxagoras. The assertion that he actually predicted this fall in
any proper sense of the word would be obviously absurd. Yet the fact
that his name is associated with it suggests that he had studied similar
meteorites, or else that he studied this particular one, since it
is not quite clear whether it was before or after this fall that he
made the famous assertion that space is full of falling stones. We
should stretch the probabilities were we to assert that Anaxagoras
knew that shooting-stars and meteors were the same, yet there is an
interesting suggestiveness in his likening the shooting-stars to sparks
leaping from the firmament, taken in connection with his observation
on meteorites. Be this as it may, the fact that something which falls
from heaven as a blazing light turns out to be an iron-like mass may
very well have suggested to the most rational of thinkers that the
great blazing light called the sun has the same composition. This
idea grasped, it was a not unnatural extension to conceive the other
heavenly bodies as having the same composition.

This led to a truly startling thought. Since the heavenly bodies are
of the same composition as the earth, and since they are observed
to be whirling about the earth in space, may we not suppose that they
were once a part of the earth itself, and that they have been thrown
off by the force of a whirling motion? Such was the conclusion which
Anaxagoras reached; such his explanation of the origin of the heavenly
bodies. It was a marvellous guess. Deduct from it all that recent
science has shown to be untrue; bear in mind that the stars are suns,
compared with which the earth is a mere speck of dust; recall that
the sun is parent, not daughter, of the earth, and despite all these
deductions, the cosmogonic guess of Anaxagoras remains, as it seems
to us, one of the most marvellous feats of human intelligence. It
was the first explanation of the cosmic bodies that could be called,
in any sense, an anticipation of what the science of our own day accepts
as a true explanation of cosmic origins. Moreover, let us urge again
that this was no mere accidental flight of the imagination; it was
a scientific induction based on the only data available; perhaps it
is not too much to say that it was the only scientific induction which
these data would fairly sustain. Of course it is not for a moment
to be inferred that Anaxagoras understood, in the modern sense, the
character of that whirling force which we call centrifugal. About
two thousand years were yet to elapse before that force was explained
as elementary inertia; and even that explanation, let us not forget,
merely sufficed to push back the barriers of mystery by one other
stage; for even in our day inertia is a statement of fact rather than
an explanation.

But however little Anaxagoras could explain the centrifugal force
on mechanical principles, the practical powers of that force were
sufficiently open to his observation. The mere experiment of throwing
a stone from a sling would, to an observing mind, be full of suggestiveness.
It would be obvious that by whirling the sling about, the stone which
it held would be sustained in its circling path about the hand in
seeming defiance of the earth's pull, and after the stone had left
the sling, it could fly away from the earth to a distance which the
most casual observation would prove to be proportionate to the speed
of its flight. Extremely rapid motion, then, might project bodies
from the earth's surface off into space; a sufficiently rapid whirl
would keep them there. Anaxagoras conceived that this was precisely
what had occurred. His imagination even carried him a step farther---to
a conception of a slackening of speed, through which the heavenly
bodies would lose their centrifugal force, and, responding to the
perpetual pull of gravitation, would fall back to the earth, just
as the great stone at \AE{}gespotomi had been observed to do.

Here we would seem to have a clear conception of the idea of universal
gravitation, and Anaxagoras stands before us as the anticipator of
Newton. Were it not for one scientific maxim, we might exalt the old
Greek above the greatest of modern natural philosophers; but that
maxim bids us pause. It is phrased thus, {}``He discovers who proves.''
Anaxagoras could not prove; his argument was at best suggestive, not
demonstrative. He did not even know the laws which govern falling
bodies; much less could he apply such laws, even had he known them,
to sidereal bodies at whose size and distance he could only guess
in the vaguest terms. Still his cosmogonic speculation remains as
perhaps the most remarkable one of antiquity. How widely his speculation
found currency among his immediate successors is instanced in a passage
from Plato, where Socrates is represented as scornfully answering
a calumniator in these terms: {}``He asserts that I say the sun is
a stone and the moon an earth. Do you think of accusing Anaxagoras,
Miletas, and have you so low an opinion of these men, and think them
so unskilled in laws, as not to know that the books of Anaxagoras
the Clazomen\ae{}an are full of these doctrines. And forsooth the
young men are learning these matters from me which sometimes they
can buy from the orchestra for a drachma, at the most, and laugh at
Socrates if he pretends they are his---particularly seeing they are
so strange.''

The element of error contained in these cosmogonic speculations of
Anaxagoras has led critics to do them something less than justice.
But there is one other astronomical speculation for which the Clazomen\ae{}an
philosopher has received full credit. It is generally admitted that
it was he who first found out the explanation of the phases of the
moon; a knowledge that that body shines only by reflected light, and
that its visible forms, waxing and waning month by month from crescent
to disk and from disk to crescent, merely represent our shifting view
of its sun-illumined face. It is difficult to put ourselves in the
place of the ancient observer and realize how little the appearances
suggest the actual fact. That a body of the same structure as the
earth should shine with the radiance of the moon merely because sunlight
is reflected from it, is in itself a supposition seemingly contradicted
by ordinary experience. It required the mind of a philosopher, sustained,
perhaps, by some experimental observations, to conceive the idea that
what seems so obviously bright may be in reality dark. The germ of
the conception of what the philosopher speaks of as the noumena, or
actualities, back of phenomena or appearances, had perhaps this crude
beginning. Anaxagoras could surely point to the moon in support of
his seeming paradox that snow, being really composed of water, which
is dark, is in reality black and not white---a contention to which
we shall refer more at length in a moment.

But there is yet another striking thought connected with this new
explanation of the phases of the moon. The explanation implies not
merely the reflection of light by a dark body, but by a dark body
of a particular form. Granted that reflections are in question, no
body but a spherical one could give an appearance which the moon presents.
The moon, then, is not merely a mass of earth, it is a spherical mass
of earth. Here there were no flaws in the reasoning of Anaxagoras.
By scientific induction he passed from observation to explanation.
A new and most important element was added to the science of astronomy.

Looking back from the latter-day stand-point, it would seem as if
the mind of the philosopher must have taken one other step: the mind
that had conceived sun, moon, stars, and earth to be of one substance
might naturally, we should think, have reached out to the further
induction that, since the moon is a sphere, the other cosmic bodies,
including the earth, must be spheres also. But generalizer as he was,
Anaxagoras was too rigidly scientific a thinker to make this assumption.
The data at his command did not, as he analyzed them, seem to point
to this conclusion. We have seen that Pythagoras probably, and Parmenides
surely, out there in Italy had conceived the idea of the earth's rotundity,
but the Pythagorean doctrines were not rapidly taken up in the mother-country,
and Parmenides, it must be recalled, was a strict contemporary of
Anaxagoras himself. It is no reproach, therefore, to the Clazomen\ae{}an
philosopher that he should have held to the old idea that the earth
is flat, or at most a convex disk---the latter being the Babylonian
conception which probably dominated that Milesian school to which
Anaxagoras harked back.

Anaxagoras may never have seen an eclipse of the moon, and even if
he had he might have reflected that, from certain directions, a disk
may throw precisely the same shadow as a sphere. Moreover, in reference
to the shadow cast by the earth, there was, so Anaxagoras believed,
an observation open to him nightly which, we may well suppose, was
not without influence in suggesting to his mind the probable shape
of the earth. The Milky Way, which doubtless had puzzled astronomers
from the beginnings of history and which was to continue to puzzle
them for many centuries after the day of Anaxagoras, was explained
by the Clazomen\ae{}an philosopher on a theory obviously suggested
by the theory of the moon's phases. Since the earth-\ like moon shines
by reflected light at night, and since the stars seem obviously brighter
on dark nights, Anaxagoras was but following up a perfectly logical
induction when he propounded the theory that the stars in the Milky
Way seem more numerous and brighter than those of any other part of
the heavens, merely because the Milky Way marks the shadow of the
earth. Of course the inference was wrong, so far as the shadow of
the earth is concerned; yet it contained a part truth, the force of
which was never fully recognized until the time of Galileo. This consists
in the assertion that the brightness of the Milky Way is merely due
to the glow of many stars. The shadow-\ theory of Anaxagoras would
naturally cease to have validity so soon as the sphericity of the
earth was proved, and with it, seemingly, fell for the time the companion
theory that the Milky Way is made up of a multitude of stars.

It has been said by a modern critic%
\footnote{\textit{\emph{Theodor}} Gomperz, \emph{Greek Thinkers: a History of
Ancient Philosophy} (translated from the German by Laurie \textit{\emph{Magnes}}),
\textit{\emph{New}} York, 190 1, \textit{\emph{pp}}.\ 220, 221.%
} that the shadow-theory was childish in that it failed to note that
the Milky Way does not follow the course of the ecliptic. But this
criticism only holds good so long as we reflect on the true character
of the earth as a symmetrical body poised in space. It is quite possible
to conceive a body occupying the position of the earth with reference
to the sun which would cast a shadow having such a tenuous form as
the Milky Way presents. Such a body obviously would not be a globe,
but a long-drawn-out, attenuated figure. There is, to be sure, no
direct evidence preserved to show that Anaxagoras conceived the world
to present such a figure as this, but what we know of that philosopher's
close-reasoning, logical mind gives some warrant to the assumption---gratuitous
though in a sense it be---that the author of the theory of the moon's
phases had not failed to ask himself what must be the form of that
terrestrial body which could cast the tenuous shadow of the Milky
Way. Moreover, we must recall that the habitable earth, as known to
the Greeks of that day, was a relatively narrow band of territory,
stretching far to the east and to the west.


\subsection*{\raggedright Anaxagoras as Meteorologist}

\addcontentsline{toc}{subsection}{Anaxagoras as Meteorologist}

The man who had studied the meteorite of \AE{}gospotami, and been
put by it on the track of such remarkable inductions, was, naturally,
not oblivious to the other phenomena of the atmosphere. Indeed, such
a mind as that of Anaxagoras was sure to investigate all manner of
natural phenomena, and almost equally sure to throw new light on any
subject that it investigated. Hence it is not surprising to find Anaxagoras
credited with explaining the winds as due to the \textit{\emph{rarefactions}}
of the atmosphere produced by the sun. This explanation gives Anaxagoras
full right to be called {}``the father of meteorology,''\ a title
which, it may be, no one has thought of applying to him, chiefly because
the science of meteorology did not make its real beginnings until
some twenty-four hundred years after the death of its first great
votary. Not content with explaining the winds, this prototype of Franklin
turned his attention even to the upper atmosphere. {}``Thunder,''\ he
is reputed to have said, {}``was produced by the collision of the
clouds, and lightning by the rubbing together of the clouds.'' We
dare not go so far as to suggest that this implies an association
in the mind of Anaxagoras between the friction of the clouds and the
observed electrical effects generated by the friction of such a substance
as amber. To make such a suggestion doubtless would be to fall victim
to the old familiar propensity to read into Homer things that Homer
never knew. Yet the significant fact remains that Anaxagoras ascribed
to thunder and to lightning their true position as strictly natural
phenomena. For him it was no god that menaced humanity with thundering
voice and the flash of his divine fires from the clouds. Little wonder
that the thinker whose science carried him to such scepticism as this
should have felt the wrath of the superstitious Athenians.


\subsection*{\raggedright Biological Speculations}

\addcontentsline{toc}{subsection}{Biological Speculations}

Passing from the phenomena of the air to those of the earth itself,
we learn that Anaxagoras explained an earthquake as being produced
by the returning of air into the earth. We cannot be sure as to the
exact meaning here, though the idea that gases are imprisoned in the
substance of the earth seems not far afield. But a far more remarkable
insight than this would imply was shown by Anaxagoras when he asserted
that a certain amount of air is contained in water, and that fishes
breathe this air. The passage of Aristotle in which this opinion is
ascribed to Anaxagoras is of sufficient interest to be quoted at length:\ 

{}``Democritus, of Abdera,''\ says Aristotle, {}``and some others,
that have spoken concerning respiration, have determined nothing concerning
other animals, but seem to have supposed that all animals respire.
But Anaxagoras and Diogenes (Apolloniates), who say that all animals
respire, have also endeavored to explain how fishes, and all those
animals that have a hard, rough shell, such as oysters, mussels, \textit{etc}.,
respire. And Anaxagoras, indeed, says that fishes, when they emit
water through their gills, attract air from the mouth to the vacuum
in the viscera from the water which surrounds the mouth; as if air
was inherent in the water.''%
\footnote{Aristotle's \emph{Treatise on} \textit{Respiration}, \textit{\emph{ch}}.\ ii.%
}

It should be recalled that of the three philosophers thus mentioned
as contending that all animals respire, Anaxagoras was the elder;
he, therefore, was presumably the originator of the idea. It will
be observed, too, that Anaxagoras alone is held responsible for the
idea that fishes respire air through their gills, {}``attracting''\ it
from the water. This certainly was one of the shrewdest physiological
guesses of any age, if it be regarded as a mere guess. With greater
justice we might refer to it as a profound deduction from the principle
of the uniformity of nature.

In making such a deduction, Anaxagoras was far in advance of his time
as illustrated by the fact that Aristotle makes the citation we have
just quoted merely to add that {}``such things are impossible,''\ and
to refute these {}``impossible''\ ideas by means of metaphysical
reasonings that seemed demonstrative not merely to himself, but to
many generations of his followers.

We are told that Anaxagoras alleged that all animals were originally
generated out of moisture, heat, and earth particles. Just what opinion
he held concerning man's development we are not informed. Yet there
is one of his phrases which suggests---without, perhaps, quite proving---that
he was an evolutionist. This phrase asserts, with insight that is
fairly startling, that man is the most intelligent of animals because
he has hands. The man who could make that assertion must, it would
seem, have had in mind the idea of the development of intelligence
through the use of hands---\ an idea the full force of which was
not evident to subsequent generations of thinkers until the time of
Darwin.


\subsection*{\raggedright Physical Speculations}

\addcontentsline{toc}{subsection}{Physical Speculations}

Anaxagoras is cited by Aristotle as believing that {}``plants are
animals and feel pleasure and pain, inferring this because they shed
their leaves and let them grow again.'' The idea is fanciful, yet
it suggests again a truly philosophical conception of the unity of
nature. The man who could conceive that idea was but little hampered
by traditional conceptions. He was exercising a rare combination of
the rigidly scientific spirit with the poetical imagination. He who
possesses these gifts is sure not to stop in his questionings of nature
until he has found some thinkable explanation of the character of
matter itself. Anaxagoras found such an explanation, and, as good
luck would have it, that explanation has been preserved. Let us examine
his reasoning in some detail. We have already referred to the claim
alleged to have been made by Anaxagoras that snow is not really white,
but black. The philosopher explained his paradox, we are told, by
asserting that snow is really water, and that water is dark, when
viewed under proper conditions---as at the bottom of a well. That
idea contains the germ of the Clazomen\ae{}an philosopher's conception
of the nature of matter. Indeed, it is not unlikely that this theory
of matter grew out of his observation of the changing forms of water.
He seems clearly to have grasped the idea that snow on the one hand,
and vapor on the other, are of the same intimate substance as the
water from which they are derived and into which they may be again
transformed. The fact that steam and snow can be changed back into
water, and by simple manipulation cannot be changed into any other
substance, finds, as we now believe, its true explanation in the fact
that the molecular structure, as we phrase it---that is to say, the
ultimate particle of which water is composed, is not changed, and
this is precisely the explanation which Anaxagoras gave of the same
phenomena. For him the unit particle of water constituted an elementary
body, uncreated, unchangeable, indestructible. This particle, in association
with like particles, constitutes the substance which we call water.
The same particle in association with particles unlike itself, might
produce totally different substances---as, for example, when water
is taken up by the roots of a plant and becomes, seemingly, a part
of the substance of the plant. But whatever the changed association,
so Anaxagoras reasoned, the ultimate particle of water remains a particle
of water still. And what was true of water was true also, so he conceived,
of every other substance. Gold, silver, iron, earth, and the various
vegetables and animal tissues---in short, each and every one of all
the different substances with which experience makes us familiar,
is made up of unit particles which maintain their integrity in whatever
combination they may be associated. This implies, obviously, a multitude
of primordial particles, each one having an individuality of its own;
each one, like the particle of water already cited, uncreated, unchangeable,
and indestructible.

Fortunately, we have the philosopher's own words to guide us as to
his speculations here. The fragments of his writings that have come
down to us (chiefly through the quotations of \textit{\emph{Simplicius}})
deal almost exclusively with these ultimate conceptions of his imagination.
In ascribing to him, then, this conception of diverse, uncreated,
primordial elements, which can never be changed, but can only be mixed
together to form substances of the material world, we are not reading
back post-Daltonian knowledge into the system of Anaxagoras. Here
are his words: {}``The Greeks do not rightly use the terms `coming
into being'\ and `perishing.' For nothing comes into being, nor,
yet, does anything perish; but there is mixture and separation of
things that are. So they would do right in calling `coming into being'\ `mixture'\ and
`perishing' `separation.' For how could hair come from what is not
hair? Or flesh from what is not flesh?''

Elsewhere he tells us that (at one stage of the world's development)\ {}``the
dense, the moist, the cold, the dark, collected there where now is
earth; the rare, the warm, the dry, the bright, departed towards the
further part of the \ae{}\textit{\emph{ther}}. The earth is condensed
out of these things that are separated, for water is separated from
the clouds, and earth from the water; and from the earth stones are
condensed by the cold, and these are separated farther from the water.''
Here again the influence of heat and cold in determining physical
qualities is kept pre-eminently in mind. The dense, the moist, the
cold, the dark are contrasted with the rare, the warm, the dry, and
bright; and the formation of stones is spoken of as a specific condensation
due to the influence of cold. Here, then, we have nearly all the elements
of the Daltonian theory of atoms on the one hand, and the nebular
hypothesis of Laplace on the other. But this is not quite all. In
addition to such diverse elementary particles as those of gold, water,
and the rest, Anaxagoras conceived a species of particles differing
from all the others, not merely as they differ from one another, but
constituting a class by themselves; particles infinitely smaller than
the others; particles that are described as infinite, self-powerful,
mixed with nothing, but existing alone. That is to say (interpreting
the theory in the only way that seems plausible), these most minute
particles do not mix with the other primordial particles to form material
substances in the same way in which these mixed with one another.
But, on the other hand, these {}``infinite, self-powerful, and unmixed''\ particles
commingle everywhere and in every substance whatever with the mixed
particles that go to make up the substances.

There is a distinction here, it will be observed, which at once suggests
the modern distinction between physical processes and chemical processes,
or, putting it otherwise, between molecular processes and atomic processes;
but the reader must be guarded against supposing that Anaxagoras had
any such thought as this in mind. His ultimate mixable particles can
be compared only with the Daltonian atom, not with the molecule of
the modern physicist, and his {}``infinite, self-powerful, and unmixable''
particles are not comparable with anything but the ether of the modern
physicist, with which hypothetical substance they have many points
of resemblance. But the {}``infinite, self-\ powerful, and unmixed''\ particles
constituting thus an ether-like plenum which permeates all material
structures, have also, in the mind of Anaxagoras, a function which
carries them perhaps a stage beyond the province of the modern ether.
For these {}``infinite, self powerful, and unmixed''\ particles
are imbued with, and, indeed, themselves constitute, what Anaxagoras
terms \emph{nous}, a word which the modern translator has usually
paraphrased as {}``mind.'' Neither that word nor any other available
one probably conveys an accurate idea of what Anaxagoras meant to
imply by the word nous. For him the word meant not merely {}``mind''\ in
the sense of receptive and comprehending intelligence, but directive
and creative intelligence as well. Again let Anaxagoras speak for
himself: {}``Other things include a portion of everything, but nous
is infinite, and self-powerful, and mixed with nothing, but it exists
alone, itself by itself. For if it were not by itself, but were mixed
with anything else, it would include parts of all things, if it were
mixed with anything; for a portion of everything exists in every thing,
as has been said by me before, and things mingled with it would prevent
it from having power over anything in the same way that it does now
that it is alone by itself. For it is the most rarefied of all things
and the purest, and it has all knowledge in regard to everything and
the greatest power; over all that has life, both greater and less,
nous rules. And nous ruled the rotation of the whole, so that it set
it in rotation in the beginning. First it began the rotation from
a small beginning, then more and more was included in the motion,
and yet more will be included. Both the mixed and the separated and
distinct, all things nous recognized. And whatever things were to
be, and whatever things were, as many as are now, and whatever things
shall be, all these nous arranged in order; and it arranged that rotation,
according to which now rotate stars and sun and moon and air and \ae{}\textit{\emph{ther}},
now that they are separated. Rotation itself caused the separation,
and the dense is separated from the rare, the warm from the cold,
the bright from the dark, the dry from the moist. And when nous began
to set things in motion, there was separation from everything that
was in motion, all this was made distinct. The rotation of the things
that were moved and made distinct caused them to be yet more distinct.''%
\footnote{Fairbanks'\ translation of the fragments of Anaxagoras, in \emph{The
First Philosophers of Greece}, \textit{\emph{pp}}.\ 239-243.%
}

Nous, then, as Anaxagoras conceives it, is {}``the most rarefied
of all things, and the purest, and it has knowledge in regard to everything
and the greatest power; over all that has life, both greater and less,
it rules.'' But these are postulants of omnipresence and omniscience.
In other words, nous is nothing less than the omnipotent artificer
of the material universe. It lacks nothing of the power of deity,
save only that we are not assured that it created the primordial particles.
The creation of these particles was a conception that for Anaxagoras,
as for the modern Spencer, lay beyond the range of imagination. Nous
is the artificer, working with {}``uncreated''\ particles. Back
of nous and the particles lies, for an Anaxagoras as for a Spencer,
the Unknowable. But nous itself is the equivalent of that universal
energy of motion which science recognizes as operating between the
particles of matter, and which the theologist personifies as Deity.
It is Pantheistic deity as Anaxagoras conceives it; his may be called
the first scientific conception of a non-anthropomorphic god. In elaborating
this conception Anaxagoras proved himself one of the most remarkable
scientific dreamers of antiquity. To have substituted for the Greek
Pantheon of anthropomorphic deities the conception of a non-anthropomorphic
immaterial and ethereal entity, of all things in the world {}``the
most rarefied and the purest,''\ is to have performed a feat which,
considering the age and the environment in which it was accomplished,
staggers the imagination. As a strictly scientific accomplishment
the great thinker's conception of primordial elements contained a
germ of the truth which was to lie dormant for 2200 years, but which
then, as modified and vitalized by the genius of Dalton, was to dominate
the new chemical science of the nineteenth century. If there are intimations
that the primordial element of Anaxagoras and of Dalton may turn out
in the near future to be itself a compound, there will still remain
the yet finer particles of the nous of Anaxagoras to baffle the most
subtle analysis of which to-day's science gives us any pre-vision.
All in all, then, the work of Anaxagoras must stand as that of perhaps
the most far-seeing scientific imagination of pre-Socratic antiquity.


\section*{\raggedright LEUCIPPUS AND DEMOCRITUS}

\addcontentsline{toc}{section}{LEUCIPPUS AND DEMOCRITUS}

But we must not leave this alluring field of speculation as to the
nature of matter without referring to another scientific guess, which
soon followed that of Anaxagoras and was destined to gain even wider
fame, and which in modern times has been somewhat unjustly held to
eclipse the glory of the other achievement. We mean, of course, the
atomic theory of Leucippus and Democritus. This theory reduced all
matter to primordial elements, called atoms \emph{$\alpha $$\tau $o$\mu $$\alpha $}
because they are by hypothesis incapable of further division. These
atoms, making up the entire material universe, are in this theory
conceived as qualitatively identical, differing from one another only
in size and perhaps in shape. The union of different-sized atoms in
endless combinations produces the diverse substances with which our
senses make us familiar.

Before we pass to a consideration of this alluring theory, and particularly
to a comparison of it with the theory of Anaxagoras, we must catch
a glimpse of the personality of the men to whom the theory owes its
origin. One of these, Leucippus, presents so uncertain a figure as
to be almost mythical. Indeed, it was long questioned whether such
a man had actually lived, or whether be were not really an invention
of his alleged disciple, Democritus. Latter-day scholarship, however,
accepts him as a real personage, though knowing scarcely more of him
than that he was the author of the famous theory with which his name
was associated. It is suggested that he was a wanderer, like most
philosophers of his time, and that later in life he came to Abdera,
in Thrace, and through this circumstance became the teacher of Democritus.
This fable answers as well as another. What we really know is that
Democritus himself, through whose writings and teachings the atomic
theory gained vogue, was born in Abdera, about the year 460 B.C.---that
is to say, just about the time when his great precursor, Anaxagoras,
was migrating to Athens. Democritus, like most others of the early
Greek thinkers, lives in tradition as a picturesque figure. It is
vaguely reported that he travelled for a time, perhaps in the East
and in Egypt, and that then he settled down to spend the remainder
of his life in Abdera. Whether or not he visited Athens in the course
of his wanderings we do not know. At Abdera he was revered as a sage,
but his influence upon the practical civilization of the time was
not marked. He was pre-eminently a dreamer and a writer. Like his
confreres of the epoch, he entered all fields of thought. He wrote
voluminously, but, unfortunately, his writings have, for the most
part, perished. The fables and traditions of a later day asserted
that Democritus had voluntarily put out his own eyes that he might
turn his thoughts inward with more concentration. Doubtless this is
fiction, yet, as usual with such fictions, it contains a germ of truth;
for we may well suppose that the promulgator of the atomic theory
was a man whose mind was attracted by the subtleties of thought rather
than by the tangibilities of observation. Yet the term {}``laughing
philosopher,''\ which seems to have been universally applied to
Democritus, suggests a mind not altogether withdrawn from the world
of practicalities.

So much for Democritus the man. Let us return now to his theory of
atoms. This theory, it must be confessed, made no very great impression
upon his contemporaries. It found an expositor, a little later, in
the philosopher Epicurus, and later still the poet Lucretius gave
it popular expression. But it seemed scarcely more than the dream
of a philosopher or the vagary of a poet until the day when modern
science began to penetrate the mysteries of matter. When, finally,
the researches of Dalton and his followers had placed the atomic theory
on a surer footing as the foundation of modern chemistry, the ideas
of the old laughing philosopher of Abdera, which all along had been
half derisively remembered, were recalled with a new interest. Now
it appeared that these ideas had curiously foreshadowed nineteenth-century
knowledge. It appeared that away back in the fifth century B.C.\ a
man had dreamed out a conception of the ultimate nature of matter
which had waited all these centuries for corroboration. And now the
historians of philosophy became more than anxious to do justice to
the memory of Democritus.

It is possible that this effort at poetical restitution has carried
the enthusiast too far. There is, indeed, a curious suggestiveness
in the theory of Democritus; there is philosophical allurement in
his reduction of all matter to a single element; it contains, it may
be, not merely a germ of the science of the nineteenth-century chemistry,
but perhaps the germs also of the yet undeveloped chemistry of the
twentieth century. Yet we dare suggest that in their enthusiasm for
the atomic theory of Democritus the historians of our generation have
done something less than justice to that philosopher's precursor,
Anaxagoras. And one suspects that the mere accident of a name has
been instrumental in producing this result. Democritus called his
primordial element an atom; Anaxagoras, too, conceived a primordial
element, but he called it merely a seed or thing; he failed to christen
it distinctively. Modern science adopted the word atom and gave it
universal vogue. It owed a debt of gratitude to Democritus for supplying
it the word, but it somewhat overpaid the debt in too closely linking
the new meaning of the word with its old original one. For, let it
be clearly understood, the Daltonian atom is not precisely comparable
with the atom of Democritus. The atom, as Democritus conceived it,
was monistic; all atoms, according to this hypothesis, are of the
same substance; one atom differs from another merely in size and shape,
but not at all in quality. But the Daltonian hypothesis conceived,
and nearly all the experimental efforts of the nineteenth century
seemed to prove, that there are numerous classes of atoms, each differing
in its very essence from the others.

As the case stands to-day the chemist deals with seventy-odd substances,
which he calls elements. Each one of these substances is, as he conceives
it, made up of elementary atoms having a unique personality, each
differing in quality from all the others. As far as experiment has
thus far safely carried us, the atom of gold is a primordial element
which remains an atom of gold and nothing else, no matter with what
other atoms it is associated. So, too, of the atom of silver, or zinc,
or sodium---in short, of each and every one of the seventy-odd elements.
There are, indeed, as we shall see, experiments that suggest the dissolution
of the atom---that suggest, in short, that the Daltonian atom is misnamed,
being a structure that may, under certain conditions, be broken asunder.
But these experiments have, as yet, the warrant rather of philosophy
than of pure science, and to-day we demand that the philosophy of
science shall be the handmaid of experiment.

When experiment shall have demonstrated that the Daltonian atom is
a compound, and that in truth there is but a single true atom, which,
combining with its fellows perhaps in varying numbers and in different
special relations, produces the Daltonian atoms, then the philosophical
theory of monism will have the experimental warrant which to-day it
lacks; then we shall be a step nearer to the atom of Democritus in
one direction, a step farther away in the other. We shall be nearer,
in that the conception of Democritus was, in a sense, monistic; farther
away, in that all the atoms of Democritus, large and small alike,
were considered as permanently fixed in size. Democritus postulated
all his atoms as of the same substance, differing not at all in quality;
yet he was obliged to conceive that the varying size of the atoms
gave to them varying functions which amounted to qualitative differences.
He might claim for his largest atom the same quality of substance
as for his smallest, but so long as he conceived that the large atoms,
when adjusted together to form a tangible substance, formed a substance
different in quality from the substance which the small atoms would
make up when similarly grouped, this concession amounts to the predication
of difference of quality between the atoms themselves. The entire
question reduces itself virtually to a quibble over the word quality,
So long as one atom conceived to be primordial and indivisible is
conceded to be of such a nature as necessarily to produce a different
impression on our senses, when grouped with its fellows, from the
impression produced by other atoms when similarly grouped, such primordial
atoms do differ among themselves in precisely the same way for all
practical purposes as do the primordial elements of Anaxagoras.

The monistic conception towards which twentieth-\ century chemistry
seems to be carrying us may perhaps show that all the so-called atoms
are compounded of a single element. All the true atoms making up that
element may then properly be said to have the same quality, but none
the less will it remain true that the combinations of that element
that go to make up the different Daltonian atoms differ from one another
in quality in precisely the same sense in which such tangible substances
as gold, and oxygen, and mercury, and diamonds differ from one another.
In the last analysis of the monistic philosophy, there is but one
substance and one quality in the universe. In the widest view of that
philosophy, gold and oxygen and mercury and diamonds are one substance,
and, if you please, one quality. But such refinements of analysis
as this are for the transcendental philosopher, and not for the scientist.
Whatever the allurement of such reasoning, we must for the purpose
of science let words have a specific meaning, nor must we let a mere
word-jugglery blind us to the evidence of facts. That was the rock
on which Greek science foundered; it is the rock which the modern
helmsman sometimes finds it difficult to avoid. And if we mistake
not, this case of the atom of Democritus is precisely a case in point.
Because Democritus said that his atoms did not differ in quality,
the modern philosopher has seen in his theory the essentials of monism;
has discovered in it not merely a forecast of the chemistry of the
nineteenth century, but a forecast of the hypothetical chemistry of
the future. And, on the other hand, because Anaxagoras predicted a
different quality for his primordial elements, the philosopher of
our day has discredited the primordial element of Anaxagoras.

Yet if our analysis does not lead us astray, the theory of Democritus
was not truly monistic; his indestructible atoms, differing from one
another in size and shape, utterly incapable of being changed from
the form which they had maintained from the beginning, were in reality
as truly and primordially different as are the primordial elements
of Anaxagoras. In other words, the atom of Democritus is nothing less
than the primordial seed of Anaxagoras, a little more tangibly visualized
and given a distinctive name. Anaxagoras explicitly conceived his
elements as invisibly small, as infinite in number, and as made up
of an indefinite number of kinds---one for each distinctive substance
in the world. But precisely the same postulates are made of the atom
of Democritus. These also are invisibly small; these also are infinite
in number; these also are made up of an indefinite number of kinds,
corresponding with the observed difference of substances in the world.
{}``Primitive seeds,''\ or {}``atoms,''\ were alike conceived
to be primordial, unchangeable, and indestructible. Wherein then lies
the difference? We answer, chiefly in a name; almost solely in the
fact that Anaxagoras did not attempt to postulate the physical properties
of the elements beyond stating that each has a distinctive personality,
while Democritus did attempt to postulate these properties. He, too,
admitted that each kind of element has its distinctive personality,
and he attempted to visualize and describe the characteristics of
the personality.

Thus while Anaxagoras tells us nothing of his elements except that
they differ from one another, Democritus postulates a difference in
size, imagines some elements as heavier and some as lighter, and conceives
even that the elements may be provided with projecting hooks, with
the aid of which they link themselves one with another. No one to-day
takes these crude visualizings seriously as to their details. The
sole element of truth which these dreamings contain, as distinguishing
them from the dreamings of Anaxagoras, is in the conception that the
various atoms differ in size and weight. Here, indeed, is a vague
fore-shadowing of that chemistry of form which began to come into
prominence towards the close of the nineteenth century. To have forecast
even dimly this newest phase of chemical knowledge, across the abyss
of centuries, is indeed a feat to put Democritus in the front rank
of thinkers. But this estimate should not blind us to the fact that
the pre-vision of Democritus was but a slight elaboration of a theory
which had its origin with another thinker. The association between
Anaxagoras and Democritus cannot be directly traced, but it is an
association which the historian of ideas should never for a moment
forget. If we are not to be misled by mere word-jugglery, we shall
recognize the founder of the atomic theory of matter in Anaxagoras;
its expositors along slightly different lines in Leucippus and Democritus;
its re-discoverer of the nineteenth century in Dalton. All in all,
then, just as Anaxagoras preceded Democritus in time, so must he take
precedence over him also as an inductive thinker, who carried the
use of the scientific imagination to its farthest reach.

An analysis of the theories of the two men leads to somewhat the same
conclusion that might be reached from a comparison of their lives.
Anaxagoras was a sceptical, experimental scientist, gifted also with
the prophetic imagination. He reasoned always from the particular
to the general, after the manner of true induction, and he scarcely
took a step beyond the confines of secure induction. True scientist
that he was, he could content himself with postulating different qualities
for his elements, without pretending to know how these qualities could
be defined. His elements were by hypothesis invisible, hence he would
not attempt to visualize them. Democritus, on the other hand, refused
to recognize this barrier. Where he could not know, he still did not
hesitate to guess. Just as he conceived his atom of a definite form
with a definite structure, even so he conceived that the atmosphere
about him was full of invisible spirits; he accepted the current superstitions
of his time. Like the average Greeks of his day, he even believed
in such omens as those furnished by inspecting the entrails of a fowl.
These chance bits of biography are weather-vanes of the mind of Democritus.
They tend to substantiate our conviction that Democritus must rank
below Anaxagoras as a devotee of pure science. But, after all, such
comparisons and estimates as this are utterly futile. The essential
fact for us is that here, in the fifth century before our era, we
find put forward the most penetrating guess as to the constitution
of matter that the history of ancient thought has to present to us.
In one direction, the avenue of progress is barred; there will be
no farther step that way till we come down the centuries to the time
of Dalton.


\section*{\raggedright HIPPOCRATES AND GREEK MEDICINE}

\addcontentsline{toc}{section}{HIPPOCRATES AND GREEK\\
MEDICINE}

These studies of the constitution of matter have carried us to the
limits of the field of scientific imagination in antiquity; let us
now turn sharply and consider a department of science in which theory
joins hands with practicality. Let us witness the beginnings of scientific
therapeutics.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth,
  height=0.95\paperwidth,
  keepaspectratio]{1hsci10-Wil1S170}\end{center}

\noindent \begin{center}\noun{\small Hippocrates}\end{center}
\end{figure}
Medicine among the early Greeks, before the time of Hippocrates, was
a crude mixture of religion, necromancy, and mysticism. Temples were
erected to the god of medicine, \AE{}sculapius, and sick persons
made their way, or were carried, to these temples, where they sought
to gain the favor of the god by suitable offerings, and learn the
way to regain their health through remedies or methods revealed to
them in dreams by the god. When the patient had been thus cured, he
placed a tablet in the temple describing his sickness, and telling
by what method the god had cured him. He again made suitable offerings
at the temple, which were sometimes in the form of gold or silver
representations of the diseased organ---a gold or silver model of
a heart, hand, foot, \textit{etc}.

Nevertheless, despite this belief in the supernatural, many drugs
and healing lotions were employed, and the Greek physicians possessed
considerable skill in dressing wounds and bandaging. But they did
not depend upon these surgical dressings alone, using with them certain
appropriate prayers and incantations, recited over the injured member
at the time of applying the dressings.

Even the very early Greeks had learned something of anatomy. The daily
contact with wounds and broken bones must of necessity lead to a crude
understanding of anatomy in general. The first Greek anatomist, however,
who is recognized as such, is said to have been Alcm\ae{}on. He is
said to have made \textit{\emph{extensive}} \emph{}\textit{\emph{dissections}}
of the lower animals, and to have described many hitherto unknown
structures, such as the optic nerve and the Eustachian canal---the
small tube leading into the throat from the ear. He is credited with
many unique explanations of natural phenomena, such as, for example,
the explanation that {}``hearing is produced by the hollow bone behind
the ear; for all hollow things are sonorous.'' He was a rationalist,
and he taught that the brain is the organ of mind. The sources of
our information about his work, however, are unreliable.

Democedes, who lived in the sixth century B.C., is the first physician
of whom we have any trustworthy history. We learn from Herodotus that
he came from Croton to \AE{}gina, where, in recognition of his skill,
he was appointed medical officer of the city. From \AE{}gina he was
called to Athens at an increased salary, and later was in charge of
medical affairs in several other Greek cities. He was finally called
to Samos by the tyrant Polycrates, who reigned there from about 536
to 522 B.C. But on the death of Polycrates, who was murdered by the
Persians, Democedes became a slave. His fame as a physician, however,
had reached the ears of the Persian monarch, and shortly after his
capture he was permitted to show his skill upon King Darius himself.
The Persian monarch was suffering from a sprained ankle, which his
Egyptian surgeons had been unable to cure. Democedes not only cured
the injured member but used his influence in saving the lives of his
Egyptian rivals, who had been condemned to death by the king.

At another time he showed his skill by curing the queen, who was suffering
from a chronic abscess of long standing. This so pleased the monarch
that he offered him as a reward anything he might desire, except his
liberty. But the costly gifts of Darius did not satisfy him so long
as he remained a slave; and determined to secure his freedom at any
cost, he volunteered to lead some Persian spies into his native country,
promising to use his influence in converting some of the leading men
of his nation to the Persian cause. Laden with the wealth that had
been heaped upon him by Darius, he set forth upon his mission, but
upon reaching his native city of Croton he threw off his mask, renounced
his Persian mission, and became once more a free Greek.

While the story of Democedes throws little light upon the medical
practices of the time, it shows that paid city medical officers existed
in Greece as early as the fifth and sixth centuries B.C. Even then
there were different {}``schools''\ of medicine, whose disciples
disagreed radically in their methods of treating diseases; and there
were also specialists in certain diseases, quacks, and charlatans.
Some physicians depended entirely upon external lotions for healing
all disorders; others were {}``hydrotherapeutists''\ or {}``bath-physicians'';
while there were a host of physicians who administered a great variety
of herbs and drugs. There were also magicians who pretended to heal
by sorcery, and great numbers of bone-setters, oculists, and dentists.

Many of the wealthy physicians had hospitals, or clinics, where patients
were operated upon and treated. They were not hospitals in our modern
understanding of the term, but were more like dispensaries, where
patients were treated temporarily, but were not allowed to remain
for any length of time. Certain communities established and supported
these dispensaries for the care of the poor.

But anything approaching a rational system of medicine was not established,
until Hippocrates of Cos, the {}``father of medicine,'' came upon
the scene. In an age that produced Phidias, Lysias, Herodotus, Sophocles,
and Pericles, it seems but natural that the medical art should find
an exponent who would rise above superstitious dogmas and lay the
foundation for a medical science. His rejection of the supernatural
alone stamps the greatness of his genius. But, besides this, he introduced
more detailed observation of diseases, and demonstrated the importance
that attaches to prognosis.

Hippocrates was born at Cos, about 460 B.C., but spent most of his
life at Larissa, in Thessaly. He was educated as a physician by his
father, and travelled extensively as an itinerant practitioner for
several years. His travels in different climates and among many different
people undoubtedly tended to sharpen his keen sense of observation.
He was a practical physician as well as a theorist, and, withal, a
clear and concise writer. {}``Life is short,''\ he says, {}``opportunity
fleeting, judgment difficult, treatment easy, but treatment after
thought is proper and profitable.''

His knowledge of anatomy was necessarily very imperfect, and was gained
largely from his predecessors, to whom he gave full credit. \textit{\emph{Dissections}}
of the human body were forbidden him, and he was obliged to confine
his experimental researches to operations on the lower animals. His
knowledge of the structure and arrangement of the bones, however,
was fairly accurate, but the anatomy of the softer tissues, as he
conceived it, was a queer jumbling together of blood-vessels, muscles,
and tendons. He does refer to {}``nerves,''\ to be sure, but apparently
the structures referred to are the tendons and ligaments, rather than
the nerves themselves. He was better acquainted with the principal
organs in the cavities of the body, and knew, for example, that the
heart is divided into four cavities, two of which he supposed to contain
blood, and the other two air.

His most revolutionary step was his divorcing of the supernatural
from the natural, and establishing the fact that disease is due to
natural causes and should be treated accordingly. The effect of such
an attitude can hardly be over-estimated. The establishment of such
a theory was naturally followed by a close observation as to the course
of diseases and the effects of treatment. To facilitate this, he introduced
the custom of writing down his observations as he made them---the
{}``clinical history''\ of the case. Such clinical records are
in use all over the world to-day, and their importance is so obvious
that it is almost incomprehensible that they should have fallen into
disuse shortly after the time of Hippocrates, and not brought into
general use again until almost two thousand years later.

But scarcely less important than his recognition of disease as a natural
phenomenon was the importance he attributed to prognosis. Prognosis,
in the sense of prophecy, was common before the time of Hippocrates.
But prognosis, as he practised it and as we understand it to-day,
is prophecy based on careful observation of the course of diseases---something
more than superstitious conjecture.

Although Hippocratic medicine rested on the belief in natural causes,
nevertheless, dogma and theory held an important place. The humoral
theory of disease was an all-important one, and so fully was this
theory accepted that it influenced the science of medicine all through
succeeding centuries. According to this celebrated theory there are
four humors in the body---blood, phlegm, yellow bile, and black bile.
When these humors are mixed in exact proportions they constitute health;
but any deviations from these proportions produce disease. In treating
diseases the aim of the physician was to discover which of these humors
were out of proportion and to restore them to their natural equilibrium.
It was in the methods employed in this restitution, rather than a
disagreement about the humors themselves, that resulted in the various
{}``schools''\ of medicine.

In many ways the surgery of Hippocrates showed a better understanding
of the structure of the organs than of their functions. Some of the
surgical procedures as described by him are followed, with slight
modifications, to-day. Many of his methods were entirely lost sight
of until modern times, and one, the treatment of dislocation of the
outer end of the collar-bone, was not revived until some time in the
eighteenth century.

Hippocrates, it seems, like modern physicians, sometimes suffered
from the ingratitude of his patients. {}``The physician visits a
patient suffering from fever or a wound, and prescribes for him,''
he says; {}``on the next day, if the patient feels worse the blame
is laid upon the physician; if, on the other hand, he feels better,
nature is extolled, and the physician reaps no praise.'' The essence
of this has been repeated in rhyme and prose by writers in every age
and country, but the {}``father of medicine'' cautions physicians
against allowing it to influence their attitude towards their profession.


\chapter*{\raggedright VIII. POST-SOCRATIC SCIENCE AT ATHENS---PLATO, ARISTOTLE,
AND THEOPHRASTUS}

\addcontentsline{toc}{chapter}{VIII. POST-SOCRATIC SCIENCE AT\\
ATHENS---PLATO, ARISTOTLE, AND\\
THEOPHRASTUS}

\markboth{A HISTORY OF SCIENCE, BOOK I}{VIII. POST-SOCRATIC SCIENCE}

Doubtless it has been noticed that our earlier scientists were as
far removed as possible from the limitations of specialism. In point
of fact, in this early day, knowledge had not been classified as it
came to be later on. The philosopher was, as his name implied, a lover
of knowledge, and he did not find it beyond the reach of his capacity
to apply himself to all departments of the field of human investigation.
It is nothing strange to discover that Anaximander and the Pythagoreans
and Anaxagoras have propounded theories regarding the structure of
the cosmos, the origin and development of animals and man, and the
nature of matter itself. Nowadays, so enormously involved has become
the mass of mere facts regarding each of these departments of knowledge
that no one man has the temerity to attempt to master them all. But
it was different in those days of beginnings. Then the methods of
observation were still crude, and it was quite the custom for a thinker
of forceful personality to find an eager following among disciples
who never thought of putting his theories to the test of experiment.
The great lesson that true science in the last resort depends upon
observation and measurement, upon compass and balance, had not yet
been learned, though here and there a thinker like Anaxagoras had
gained an inkling of it.

For the moment, indeed, there in Attica, which was now, thanks to
that outburst of Periclean culture, the centre of the world's civilization,
the trend of thought was to take quite another direction. The very
year which saw the birth of Democritus at Abdera, and of Hippocrates,
marked also the birth, at Athens, of another remarkable man, whose
influence it would scarcely be possible to over-estimate. This man
was Socrates. The main facts of his history are familiar to every
one. It will be recalled that Socrates spent his entire life in Athens,
mingling everywhere with the populace; haranguing, so the tradition
goes, every one who would listen; inculcating moral lessons, and finally
incurring the disapprobation of at least a voting majority of his
fellow-citizens. He gathered about him a company of remarkable men
with Plato at their head, but this could not save him from the disapprobation
of the multitudes, at whose hands he suffered death, legally administered
after a public trial. The facts at command as to certain customs of
the Greeks at this period make it possible to raise a question as
to whether the alleged {}``corruption of youth,''\ with which Socrates
was charged, may not have had a different implication from what posterity
has preferred to ascribe to it. But this thought, almost shocking
to the modern mind and seeming altogether sacrilegious to most students
of Greek philosophy, need not here detain us; neither have we much
concern in the present connection with any part of the teaching of
the martyred philosopher. For the historian of metaphysics, Socrates
marks an epoch, but for the historian of science he is a much less
consequential figure.

Similarly regarding Plato, the aristocratic Athenian who sat at the
feet of Socrates, and through whose writings the teachings of the
master found widest currency. Some students of philosophy find in
Plato {}``the greatest thinker and writer of all time.''%
\footnote{Alfred William Bern, \emph{The Philosophy of Greece Considered in
Relation to the Character and History of its People}, London, 1898,
p.\ 186.%
} The student of science must recognize in him a thinker whose point
of view was essentially non-scientific; one who tended always to reason
from the general to the particular rather than from the particular
to the general. Plato's writings covered almost the entire field of
thought, and his ideas were presented with such literary charm that
successive generations of readers turned to them with unflagging interest,
and gave them wide currency through copies that finally preserved
them to our own time. Thus we are not obliged in his case, as we are
in the case of every other Greek philosopher, to estimate his teachings
largely from hearsay evidence. Plato himself speaks to us directly.
It is true, the literary form which he always adopted, namely, the
dialogue, does not give quite the same certainty as to when he is
expressing his own opinions that a more direct narrative would have
given; yet, in the main, there is little doubt as to the tenor of
his own opinions---except, indeed, such doubt as always attaches to
the philosophical reasoning of the abstract thinker.

What is chiefly significant from our present standpoint is that the
great ethical teacher had no significant message to give the world
regarding the physical sciences. He apparently had no sharply defined
opinions as to the mechanism of the universe; no clear conception
as to the origin or development of organic beings; no tangible ideas
as to the problems of physics; no favorite dreams as to the nature
of matter. Virtually his back was turned on this entire field of thought.
He was under the sway of those innate ideas which, as we have urged,
were among the earliest inductions of science. But he never for a
moment suspected such an origin for these ideas. He supposed his conceptions
of being, his standards of ethics, to lie back of all experience;
for him they were the most fundamental and most dependable of facts.
He criticised Anaxagoras for having tended to deduce general laws
from observation. As we moderns see it, such criticism is the highest
possible praise. It is a criticism that marks the distinction between
the scientist who is also a philosopher and the philosopher who has
but a vague notion of physical science. Plato seemed, indeed, to realize
the value of scientific investigation; he referred to the astronomical
studies of the Egyptians and Chaldeans, and spoke hopefully of the
results that might accrue were such studies to be taken up by that
Greek mind which, as he justly conceived, had the power to vitalize
and enrich all that it touched. But he told here of what he would
have others do, not of what he himself thought of doing. His voice
was prophetic, but it stimulated no worker of his own time.

Plato himself had travelled widely. It is a familiar legend that he
lived for years in Egypt, endeavoring there to penetrate the mysteries
of Egyptian science. It is said even that the rudiments of geometry
which he acquired there influenced all his later teachings. But be
that as it may, the historian of science must recognize in the founder
of the Academy a moral teacher and metaphysical dreamer and sociologist,
but not, in the modern acceptance of the term, a scientist. Those
wider phases of biological science which find their expression in
metaphysics, in ethics, in political economy, lie without our present
scope; and for the development of those subjects with which we are
more directly concerned, Plato, like his master, has a negative significance.


\section*{\raggedright ARISTOTLE (384-322 B.C.)}

\addcontentsline{toc}{section}{ARISTOTLE (384-322 B.C.)}

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S182}\end{center}

\noindent \begin{center}\noun{\small Aristotle}\end{center}
\end{figure}
When we pass to that third great Athenian teacher, Aristotle, the
case is far different. Here was a man whose name was to be received
as almost a synonym for Greek science for more than a thousand years
after his death. All through the Middle Ages his writings were to
be accepted as virtually the last word regarding the problems of nature.
We shall see that his followers actually preferred his mandate to
the testimony of their own senses. We shall see, further, that modern
science progressed somewhat in proportion as it overthrew the Aristotelian
dogmas. But the traditions of seventeen or eighteen centuries are
not easily set aside, and it is perhaps not too much to say that the
name of Aristotle stands, even in our own time, as vaguely representative
in the popular mind of all that was highest and best in the science
of antiquity. Yet, perhaps, it would not be going too far to assert
that something like a reversal of this judgment would be nearer the
truth. Aristotle did, indeed, bring together a great mass of facts
regarding animals in his work on natural history, which, being preserved,
has been deemed to entitle its author to be called the {}``father
of zoology.'' But there is no reason to suppose that any considerable
portion of this work contained matter that was novel, or recorded
observations that were original with Aristotle; and the classifications
there outlined are at best but a vague foreshadowing of the elaboration
of the science. Such as it is, however, the natural history stands
to the credit of the Stagirite. He must be credited, too, with a clear
enunciation of one most important scientific doctrine---namely, the
doctrine of the spherical figure of the earth. We have already seen
that this theory originated with the Pythagorean philosophers out
in Italy. We have seen, too, that the doctrine had not made its way
in Attica in the time of Anaxagoras. But in the intervening century
it had gained wide currency, else so essentially conservative a thinker
as Aristotle would scarcely have accepted it. He did accept it, however,
and gave the doctrine clearest and most precise expression. Here are
his words:%
\footnote{Aristotle, quoted in William Whewell's \emph{History of the Inductive
Sciences} (second edition, London, 1847), Vol.\ II., p.\ 161.%
}

\begin{quote}
{}``As to the figure of the earth it must necessarily be spherical\ldots{}.
If it were not so, the eclipses of the moon would not have such sections
as they have. For in the configurations in the course of a month the
deficient part takes all different shapes; it is straight, and concave,
and convex; but in eclipses it always has the line of divisions convex;
wherefore, since the moon is eclipsed in consequence of the interposition
of the earth, the periphery of the earth must be the cause of this
by having a spherical form. And again, from the appearance of the
stars it is clear, not only that the earth is round, but that its
size is not very large; for when we make a small removal to the south
or the north, the circle of the horizon becomes palpably different,
so that the stars overhead undergo a great change, and are not the
same to those that travel in the north and to the south. For some
stars are seen in Egypt or at Cyprus, but are not seen in the countries
to the north of these; and the stars that in the north are visible
while they make a complete circuit, there undergo a setting. So that
from this it is manifest, not only that the form of the earth is round,
but also that it is a part of a not very large sphere; for otherwise
the difference would not be so obvious to persons making so small
a change of place. Wherefore we may judge that those persons who connect
the region in the neighborhood of the pillars of Hercules with that
towards India, and who assert that in this way the sea is one, do
not assert things very improbable. They confirm this conjecture moreover
by the elephants, which are said to be of the same species towards
each extreme; as if this circumstance was a consequence of the conjunction
of the extremes. The mathematicians who try to calculate the measure
of the circumference, make it amount to four hundred thousand stadia;
whence we collect that the earth is not only spherical, but is not
large compared with the magnitude of the other stars.''
\end{quote}
{}

But in giving full meed of praise to Aristotle for the promulgation
of this doctrine of the sphericity of the earth, it must unfortunately
be added that the conservative philosopher paused without taking one
other important step. He could not accept, but, on the contrary, he
expressly repudiated, the doctrine of the earth's motion. We have
seen that this idea also was a part of the Pythagorean doctrine, and
we shall have occasion to dwell more at length on this point in a
succeeding chapter. It has even been contended by some critics that
it was the adverse conviction of the Peripatetic philosopher which,
more than any other single influence, tended to retard the progress
of the true doctrine regarding the mechanism of the heavens. Aristotle
accepted the sphericity of the earth, and that doctrine became a commonplace
of scientific knowledge, and so continued throughout classical antiquity.
But Aristotle rejected the doctrine of the earth's motion, and that
doctrine, though promulgated actively by a few contemporaries and
immediate successors of the Stagirite, was then doomed to sink out
of view for more than a thousand years. If it be a correct assumption
that the influence of Aristotle was, in a large measure, responsible
for this result, then we shall perhaps not be far astray in assuming
that the great founder of the Peripatetic school was, on the whole,
more instrumental in retarding the progress of astronomical science
that any other one man that ever lived.

The field of science in which Aristotle was pre-eminently a pathfinder
is zoology. His writings on natural history have largely been preserved,
and they constitute by far the most important contribution to the
subject that has come down to us from antiquity. They show us that
Aristotle had gained possession of the widest range of facts regarding
the animal kingdom, and, what is far more important, had attempted
to classify these facts. In so doing he became the founder of systematic
zoology. Aristotle's classification of the animal kingdom was known
and studied throughout the Middle Ages, and, in fact, remained in
vogue until superseded by that of Cuvier in the nineteenth century.
It is not to be supposed that all the terms of Aristotle's classification
originated with him. Some of the divisions are too patent to have
escaped the observation of his predecessors. Thus, for example, the
distinction between birds and fishes as separate classes of animals
is so obvious that it must appeal to a child or to a savage. But the
efforts of Aristotle extended, as we shall see, to less patent generalizations.
At the very outset, his grand division of the animal kingdom into
blood-bearing and bloodless animals implies a very broad and philosophical
conception of the entire animal kingdom. The modern physiologist does
not accept the classification, inasmuch as it is now known that colorless
fluids perform the functions of blood for all the lower organisms.
But the fact remains that Aristotle's grand divisions correspond to
the grand divisions of the Lamarckian system---vertebrates and invertebrates---\ which
every one now accepts. Aristotle, as we have said, based his classification
upon observation of the blood; Lamarck was guided by a study of the
skeleton. The fact that such diverse points of view could direct the
observer towards the same result gives, inferentially, a suggestive
lesson in what the modern physiologist calls the \textit{\emph{homologies}}
of parts of the organism.

Aristotle divides his so-called blood-bearing animals into five classes:
(1)\ Four-footed animals that bring forth their young alive; (2)\ birds;
(3)\ egg-laying four-footed animals (including what modern naturalists
call reptiles and amphibians); (4)\ whales and their allies; (5)\ fishes.
This classification, as will be observed, is not so very far afield
from the modern divisions into mammals, birds, reptiles, amphibians,
and fishes. That Aristotle should have recognized the fundamental
distinction between fishes and the fish-like whales, dolphins, and
porpoises proves the far from superficial character of his studies.
Aristotle knew that these animals breathe by means of lungs and that
they produce living young. He recognized, therefore, their affinity
with his first class of animals, even if he did not, like the modern
naturalist, consider these affinities close enough to justify bringing
the two types together into a single class.

The bloodless animals were also divided by Aristotle into five classes---namely:
(1)\ Cephalopoda (the octopus, cuttle-fish, \textit{etc}.); (2)\ weak-shelled
animals (crabs, \textit{etc}.); (3)\ insects and their allies (including
various forms, such as spiders and centipedes, which the modern classifier
prefers to place by themselves); (4)\ hard-shelled animals (clams,
oysters, snails, \textit{etc}.); (5)\ a conglomerate group of marine
forms, including star-fish, sea-urchins, and various anomalous forms
that were regarded as linking the animal to the vegetable worlds.
This classification of the lower forms of animal life continued in
vogue until Cuvier substituted for it his famous grouping into articulates,
mollusks, and radiates; which grouping in turn was in part superseded
later in the nineteenth century.

What Aristotle did for the animal kingdom his pupil, Theophrastus,
did in some measure for the vegetable kingdom. Theophrastus, however,
was much less a classifier than his master, and his work on botany,
called \emph{The Natural History of Development}, pays comparatively
slight attention to theoretical questions. It deals largely with such
practicalities as the making of charcoal, of pitch, and of resin,
and the effects of various plants on the animal organism when taken
as foods or as medicines. In this regard the work of Theophrastus,
is more nearly akin to the natural history of the famous Roman compiler,
Pliny. It remained, however, throughout antiquity as the most important
work on its subject, and it entitles Theophrastus to be called the
{}``father of botany.'' Theophrastus deals also with the mineral
kingdom after much the same fashion, and here again his work is the
most notable that was produced in antiquity.


\chapter*{\raggedright IX. GREEK SCIENCE OF THE ALEXANDRIAN OR HELLENISTIC
PERIOD}

\addcontentsline{toc}{chapter}{IX. GREEK SCIENCE OF THE\\
ALEXANDRIAN OR HELLENISTIC\\
PERIOD}

\markboth{A HISTORY OF SCIENCE, BOOK I}{IX. THE ALEXANDRIAN PERIOD}

We are entering now upon the most important scientific epoch of antiquity.
When Aristotle and Theophrastus passed from the scene, Athens ceased
to be in any sense the scientific centre of the world. That city still
retained its reminiscent glory, and cannot be ignored in the history
of culture, but no great scientific leader was ever again to be born
or to take up his permanent abode within the confines of Greece proper.
With almost cataclysmic suddenness, a new intellectual centre appeared
on the south shore of the Mediterranean. This was the city of Alexandria,
a city which Alexander the Great had founded during his brief visit
to Egypt, and which became the capital of Ptolemy Soter when he chose
Egypt as his portion of the dismembered empire of the great Macedonian.
Ptolemy had been with his master in the East, and was with him in
Babylonia when he died. He had therefore come personally in contact
with Babylonian civilization, and we cannot doubt that this had a
most important influence upon his life, and through him upon the new
civilization of the West. In point of culture, Alexandria must be
regarded as the successor of Babylon, scarcely less directly than
of Greece. Following the Babylonian model, Ptolemy erected a great
museum and began collecting a library. Before his death it was said
that he had collected no fewer than two hundred thousand manuscripts.
He had gathered also a company of great teachers and founded a school
of science which, as has just been said, made Alexandria the culture-centre
of the world.

Athens in the day of her prime had known nothing quite like this.
Such private citizens as Aristotle are known to have had libraries,
but there were no great public collections of books in Athens, or
in any other part of the Greek domain, until Ptolemy founded his famous
library. As is well known, such libraries had existed in Babylonia
for thousands of years. The character which the Ptolemaic epoch took
on was no doubt due to Babylonian influence, but quite as much to
the personal experience of Ptolemy himself as an explorer in the Far
East. The marvellous conquering journey of Alexander had enormously
widened the horizon of the Greek geographer, and stimulated the imagination
of all ranks of the people, It was but natural, then, that geography
and its parent science astronomy should occupy the attention of the
best minds in this succeeding epoch. In point of fact, such a company
of star-gazers and earth-measurers came upon the scene in this third
century B.C.\ as had never before existed anywhere in the world.
The whole trend of the time was towards mechanics. It was as if the
greatest thinkers had squarely faced about from the attitude of the
mystical philosophers of the preceding century, and had set themselves
the task of solving all the mechanical riddles of the universe, They
no longer troubled themselves about problems of {}``being''\ and
{}``becoming''; they gave but little heed to metaphysical subtleties;
they demanded that their thoughts should be gauged by objective realities.
Hence there arose a succession of great geometers, and their conceptions
were applied to the construction of new mechanical contrivances on
the one hand, and to the elaboration of theories of sidereal mechanics
on the other.

The wonderful company of men who performed the feats that are about
to be recorded did not all find their home in Alexandria, to be sure;
but they all came more or less under the Alexandrian influence. We
shall see that there are two other important centres; one out in Sicily,
almost at the confines of the Greek territory in the west; the other
in Asia Minor, notably on the island of Samos---the island which,
it will be recalled, was at an earlier day the birthplace of Pythagoras.
But whereas in the previous century colonists from the confines of
the civilized world came to Athens, now all eyes turned towards Alexandria,
and so improved were the facilities for communication that no doubt
the discoveries of one coterie of workers were known to all the others
much more quickly than had ever been possible before. We learn, for
example, that the studies of Aristarchus of Samos were definitely
known to Archimedes of Syracuse, out in Sicily. Indeed, as we shall
see, it is through a chance reference preserved in one of the writings
of Archimedes that one of the most important speculations of Aristarchus
is made known to us. This illustrates sufficiently the intercommunication
through which the thought of the Alexandrian epoch was brought into
a single channel. We no longer, as in the day of the earlier schools
of Greek philosophy, have isolated groups of thinkers. The scientific
drama is now played out upon a single stage; and if we pass, as we
shall in the present chapter, from Alexandria to Syracuse and from
Syracuse to Samos, the shift of scenes does no violence to the dramatic
unities.

Notwithstanding the number of great workers who were not properly
Alexandrians, none the less the epoch is with propriety termed Alexandrian.
Not merely in the third century B.C., but throughout the lapse of
at least four succeeding centuries, the city of Alexander and the
Ptolemies continued to hold its place as the undisputed culture-centre
of the world. During that period Rome rose to its pinnacle of glory
and began to decline, without ever challenging the intellectual supremacy
of the Egyptian city. We shall see, in a later chapter, that the Alexandrian
influences were passed on to the Mohammedan conquerors, and every
one is aware that when Alexandria was finally overthrown its place
was taken by another Greek city, Byzantium or Constantinople. But
that transfer did not occur until Alexandria had enjoyed a longer
period of supremacy as an intellectual centre than had perhaps ever
before been granted to any city, with the possible exception of Babylon.


\section*{\raggedright EUCLID (ABOUT 300 B.C.)}

\addcontentsline{toc}{section}{EUCLID (ABOUT 300 B.C.)}

Our present concern is with that first wonderful development of scientific
activity which began under the first Ptolemy, and which presents,
in the course of the first century of Alexandrian influence, the most
remarkable coterie of scientific workers and thinkers that antiquity
produced. The earliest group of these new leaders in science had at
its head a man whose name has been a household word ever since. This
was Euclid, the father of systematic geometry. Tradition has preserved
to us but little of the personality of this remarkable teacher; but,
on the other hand, his most important work has come down to us in
its entirety. \emph{The Elements of Geometry}, with which the name
of Euclid is associated in the mind of every school-boy, presented
the chief propositions of its subject in so simple and logical a form
that the work remained a textbook everywhere for more than two thousand
years. Indeed it is only now beginning to be superseded. It is not
twenty years since English mathematicians could deplore the fact that,
despite certain rather obvious defects of the work of Euclid, no better
textbook than this was available. Euclid's work, of course, gives
expression to much knowledge that did not originate with him. We have
already seen that several important propositions of geometry had been
developed by Thales, and one by Pythagoras, and that the rudiments
of the subject were at least as old as Egyptian civilization. Precisely
how much Euclid added through his own investigations cannot be ascertained.
It seems probable that he was a diffuser of knowledge rather than
an originator, but as a great teacher his fame is secure. He is credited
with an epigram which in itself might insure him perpetuity of fame:
{}``There is no royal road to geometry,''\ was his answer to Ptolemy
when that ruler had questioned whether the \emph{Elements} might not
be simplified. Doubtless this, like most similar good sayings, is
apocryphal; but whoever invented it has made the world his debtor.


\section*{\raggedright HEROPHILUS AND ERASISTRATUS}

\addcontentsline{toc}{section}{HEROPHILUS AND ERASISTRATUS}

The catholicity of Ptolemy's tastes led him, naturally enough, to
cultivate the biological no less than the physical sciences. In particular
his influence permitted an epochal advance in the field of medicine.
Two anatomists became famous through the investigations they were
permitted to make under the patronage of the enlightened ruler. These
earliest of really scientific investigators of the mechanism of the
human body were named Herophilus and Erasistratus. These two anatomists
gained their knowledge by the dissection of human bodies (theirs are
the first records that we have of such practices), and King Ptolemy
himself is said to have been present at some of these \textit{\emph{dissections}}.
They were the first to discover that the nerve-\ trunks have their
origin in the brain and spinal cord, and they are credited also with
the discovery that these nerve-trunks are of two different kinds---one
to convey motor, and the other sensory impulses. They discovered,
described, and named the coverings of the brain. The name of Herophilus
is still applied by anatomists, in honor of the discoverer, to one
of the sinuses or large canals that convey the venous blood from the
head. Herophilus also noticed and described four cavities or ventricles
in the brain, and reached the conclusion that one of these ventricles
was the seat of the soul---a belief shared until comparatively recent
times by many physiologists. He made also a careful and fairly accurate
study of the anatomy of the eye, a greatly improved the old operation
for cataract.

With the increased knowledge of anatomy came also corresponding advances
in surgery, and many experimental operations are said to have been
performed upon condemned criminals who were handed over to the surgeons
by the Ptolemies. While many modern writers have attempted to discredit
these assertions, it is not improbable that such operations were performed.
In an age when human life was held so cheap, and among a people accustomed
to torturing condemned prisoners for comparatively slight offences,
it is not unlikely that the surgeons were allowed to inflict perhaps
less painful tortures in the cause of science. Furthermore, we know
that condemned criminals were sometimes handed over to the medical
profession to be {}``operated upon and killed in whatever way they
thought best''\ even as late as the sixteenth century. Tertullian%
\footnote{Tertullian's \textit{Apologeticus}.%
} probably exaggerates, however, when he puts the number of such victims
in Alexandria at six hundred.

Had Herophilus and Erasistratus been as happy in their deductions
as to the functions of the organs as they were in their knowledge
of anatomy, the science of medicine would have been placed upon a
very high plane even in their time. Unfortunately, however, they not
only drew erroneous inferences as to the functions of the organs,
but also disagreed radically as to what functions certain organs performed,
and how diseases should be treated, even when agreeing perfectly on
the subject of anatomy itself. Their contribution to the knowledge
of the scientific treatment of diseases holds no such place, therefore,
as their anatomical investigations.

Half a century after the time of Herophilus there appeared a Greek
physician, Heraclides, whose reputation in the use of drugs far surpasses
that of the anatomists of the Alexandrian school. His reputation has
been handed down through the centuries as that of a physician, rather
than a surgeon, although in his own time he was considered one of
the great surgeons of the period. Heraclides belonged to the {}``Empiric''\ school,
which rejected anatomy as useless, depending entirely on the use of
drugs. He is thought to have been the first physician to point out
the value of opium in certain painful diseases. His prescription of
this drug for certain cases of {}``sleeplessness, spasm, cholera,
and colic,''\ shows that his use of it was not unlike that of the
modern physician in certain cases; and his treatment of fevers, by
keeping the patient's head cool and facilitating the secretions of
the body, is still recognized as {}``good practice.'' He advocated
a free use of liquids in quenching the fever patient's thirst---a
recognized therapeutic measure to-day, but one that was widely condemned
a century ago.


\section*{\raggedright ARCHIMEDES OF SYRACUSE AND THE FOUNDATION OF MECHANICS}

\addcontentsline{toc}{section}{ARCHIMEDES OF SYRACUSE AND\\
THE FOUNDATION OF\\
MECHANICS}

We do not know just when Euclid died, but as he was at the height
of his fame in the time of Ptolemy I., whose reign ended in the year
285 B.C., it is hardly probable that he was still living when a young
man named Archimedes came to Alexandria to study. Archimedes was born
in the Greek colony of Syracuse, on the island of Sicily, in the year
287 B.C. When he visited Alexandria he probably found \textit{\emph{Apollonius}}
of Perga, the pupil of Euclid, at the head of the mathematical school
there. Just how long Archimedes remained at Alexandria is not known.
When he had satisfied his curiosity or completed his studies, he returned
to Syracuse and spent his life there, chiefly under the patronage
of King \textit{\emph{Hiero}}, who seems fully to have appreciated
his abilities.

Archimedes was primarily a mathematician. Left to his own devices,
he would probably have devoted his entire time to the study of geometrical
problems. But King \textit{\emph{Hiero}} had discovered that his protege
had wonderful mechanical ingenuity, and he made good use of this discovery.
Under stress of the king's urgings, the philosopher was led to invent
a great variety of mechanical contrivances, some of them most curious
ones. Antiquity credited him with the invention of more than forty
machines, and it is these, rather than his purely mathematical discoveries,
that gave his name popular vogue both among his contemporaries and
with posterity. Every one has heard of the screw of Archimedes, through
which the paradoxical effect was produced of making water seem to
flow up hill. The best idea of this curious mechanism is obtained
if one will take in hand an ordinary corkscrew, and imagine this instrument
to be changed into a hollow tube, retaining precisely the same shape
but increased to some feet in length and to a proportionate diameter.
If one will hold the corkscrew in a slanting direction and turn it
slowly to the right, supposing that the point dips up a portion of
water each time it revolves, one can in imagination follow the flow
of that portion of water from spiral to spiral, the water always running
downward, of course, yet paradoxically being lifted higher and higher
towards the base of the corkscrew, until finally it pours out (in
the actual Archimedes'\ tube)\ at the top. There is another form
of the screw in which a revolving spiral blade operates within a cylinder,
but the principle is precisely the same. With either form water may
be lifted, by the mere turning of the screw, to any desired height.
The ingenious mechanism excited the wonder of the contemporaries of
Archimedes, as well it might. More efficient devices have superseded
it in modern times, but it still excites the admiration of all who
examine it, and its effects seem as paradoxical as ever.

Some other of the mechanisms of Archimedes have been made known to
successive generations of readers through the pages of Polybius and
Plutarch. These are the devices through which Archimedes aided King
\textit{\emph{Hiero}} to ward off the attacks of the Roman general
Marcellus, who in the course of the second Punic war laid siege to
Syracuse.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S198}\end{center}

\noindent \begin{center}\noun{\small Archimedes}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (From an old print.)}\end{center}
\end{figure}
Plutarch, in his life of Marcellus, describes the Roman's attack and
Archimedes'\ defence in much detail. Incidentally he tells us also
how Archimedes came to make the devices that rendered the siege so
famous:\ 

\begin{quotation}
{}``Marcellus himself, with threescore galleys of five rowers at
every bank, well armed and full of all sorts of artillery and fireworks,
did assault by sea, and rowed hard to the wall, having made a great
engine and device of battery, upon eight galleys chained together,
to batter the wall: trusting in the great multitude of his engines
of battery, and to all such other necessary provision as he had for
wars, as also in his own reputation. But Archimedes made light account
of all his devices, as indeed they were nothing comparable to the
engines himself had invented. This inventive art to frame instruments
and engines (which are called mechanical, or organical, so highly
commended and esteemed of all sorts of people)\ was first set forth
by Architas, and by Eudoxus: partly to beautify a little the science
of geometry by this fineness, and partly to prove and confirm by material
examples and sensible instruments, certain geometrical conclusions,
where of a man cannot find out the conceivable demonstrations by enforced
reasons and proofs. As that conclusion which instructeth one to search
out two lines mean proportional, which cannot be proved by reason
demonstrative, and yet notwithstanding is a principle and an accepted
ground for many things which are contained in the art of portraiture.
Both of them have fashioned it to the workmanship of certain instruments,
called mesolabes or mesographs, which serve to find these mean lines
proportional, by drawing certain curve lines, and overthwart and oblique
sections. But after that Plato was offended with them, and maintained
against them, that they did utterly corrupt and disgrace, the worthiness
and excellence of geometry, making it to descend from things not comprehensible
and without body, unto things sensible and material, and to bring
it to a palpable substance, where the vile and base handiwork of man
is to be employed: since that time, I say, handicraft, or the art
of engines, came to be separated from geometry, and being long time
despised by the philosophers, it came to be one of the warlike arts.

{}``But Archimedes having told King \textit{\emph{Hiero}}, his kinsman
and friend, that it was possible to remove as great a weight as he
would, with as little strength as he listed to put to it: and boasting
himself thus (as they report of him)\ and trusting to the force of
his reasons, wherewith he proved this conclusion, that if there were
another globe of earth, he was able to remove this of ours, and pass
it over to the other: King \textit{\emph{Hiero}} wondering to hear
him, required him to put his device in execution, and to make him
see by experience, some great or heavy weight removed, by little force.
So Archimedes caught hold with a hook of one of the greatest carects,
or hulks of the king (that to draw it to the shore out of the water
required a marvellous number of people to go about it, and was hardly
to be done so)\ and put a great number of men more into her, than
her ordinary burden: and he himself sitting alone at his ease far
off, without any straining at all, drawing the end of an engine with
many wheels and pulleys, fair and softly with his hand, made it come
as gently and smoothly to him, as it had floated in the sea. The king
wondering to see the sight, and knowing by proof the greatness of
his art; he prayed him to make him some engines, both to assault and
defend, in all manner of sieges and assaults. So Archimedes made him
many engines, but King \textit{\emph{Hiero}} never occupied any of
them, because he reigned the most part of his time in peace without
any wars. But this provision and munition of engines, served the Syracusan's
turn marvellously at that time: and not only the provision of the
engines ready made, but also the engineer and work-master himself,
that had invented them.

{}``Now the Syracusans, seeing themselves assaulted by the Romans,
both by sea and by land, were marvellously perplexed, and could not
tell what to say, they were so afraid: imagining it was impossible
for them to withstand so great an army. But when Archimedes fell to
handling his engines, and to set them at liberty, there flew in the
air infinite kinds of shot, and marvellous great stones, with an incredible
noise and force on the sudden, upon the footmen that came to assault
the city by land, bearing down, and tearing in pieces all those which
came against them, or in what place soever they lighted, no earthly
body being able to resist the violence of so heavy a weight: so that
all their ranks were marvellously disordered. And as for the galleys
that gave assault by sea, some were sunk with long pieces of timber
like unto the yards of ships, whereto they fasten their sails, which
were suddenly blown over the walls with force of their engines into
their galleys, and so sunk them by their over great weight.''
\end{quotation}
{}

Polybius describes what was perhaps the most important of these contrivances,
which was, he tells us, {}``a band of iron, hanging by a chain from
the beak of a machine, which was used in the following manner. The
person who, like a pilot, guided the beak, having let fall the hand,
and catched hold of the prow of any vessel, drew down the opposite
end of the machine that was on the inside of the walls. And when the
vessel was thus raised erect upon its stem, the machine itself was
held immovable; but, the chain being suddenly loosened from the beak
by the means of pulleys, some of the vessels were thrown upon their
sides, others turned with the bottom upwards; and the greatest part,
as the prows were plunged from a considerable height into the sea,
were filled with water, and all that were on board thrown into tumult
and disorder.

\begin{quote}
{}``Marcellus was in no small degree embarrassed,''\ Polybius continues,
{}``when he found himself encountered in every attempt by such resistance.
He perceived that all his efforts were defeated with loss; and were
even derided by the enemy. But, amidst all the anxiety that he suffered,
he could not help jesting upon the inventions of Archimedes. This
man, said he, employs our ships as buckets to draw water: and boxing
about our sackbuts, as if they were unworthy to be associated with
him, drives them from his company with disgrace. Such was the success
of the siege on the side of the sea.''
\end{quote}
{}

Subsequently, however, Marcellus took the city by strategy, and Archimedes
was killed, contrary, it is said, to the express orders of Marcellus. 

\begin{quote}
{}``Syracuse being taken,''\ says Plutarch, {}``nothing grieved
Marcellus more than the loss of Archimedes. Who, being in his study
when the city was taken, busily seeking out by himself the demonstration
of some geometrical proposition which he had drawn in figure, and
so earnestly occupied therein, as he neither saw nor heard any noise
of enemies that ran up and down the city, and much less knew it was
taken: he wondered when he saw a soldier by him, that bade him go
with him to Marcellus. Notwithstanding, he spake to the soldier, and
bade him tarry until he had done his conclusion, and brought it to
demonstration: but the soldier being angry with his answer, drew out
his sword and killed him. Others say, that the Roman soldier when
he came, offered the sword's point to him, to kill him: and that Archimedes
when he saw him, prayed him to hold his hand a little, that he might
not leave the matter he looked for imperfect, without demonstration.
But the soldier making no reckoning of his speculation, killed him
presently. It is reported a third way also, saying that certain soldiers
met him in the streets going to Marcellus, carrying certain mathematical
instruments in a little pretty coffer, as dials for the sun, spheres,
and angles, wherewith they measure the greatness of the body of the
sun by view: and they supposing he had carried some gold or silver,
or other precious jewels in that little coffer, slew him for it. But
it is most certain that Marcellus was marvellously sorry for his death,
and ever after hated the villain that slew him, as a cursed and execrable
person: and how he had made also marvellous much afterwards of Archimedes'
kinsmen for his sake.''
\end{quote}
{}

We are further indebted to Plutarch for a summary of the character
and influence of Archimedes, and for an interesting suggestion as
to the estimate which the great philosopher put upon the relative
importance of his own discoveries. 

\begin{quote}
{}``Notwithstanding Archimedes had such a great mind, and was so
profoundly learned, having hidden in him the only treasure and secrets
of geometrical inventions: as he would never set forth any book how
to make all these warlike engines, which won him at that time the
fame and glory, not of man's knowledge, but rather of divine wisdom.
But he esteeming all kind of handicraft and invention to make engines,
and generally all manner of sciences bringing common commodity by
the use of them, to be but vile, beggarly, and mercenary dross: employed
his wit and study only to write things, the beauty and subtlety whereof
were not mingled anything at all with necessity. For all that he hath
written, are geometrical propositions, which are without comparison
of any other writings whatsoever: because the subject where of they
treat, doth appear by demonstration, the maker gives them the grace
and the greatness, and the demonstration proving it so exquisitely,
with wonderful reason and facility, as it is not repugnable. For in
all geometry are not to be found more profound and difficult matters
written, in more plain and simple terms, and by more easy principles,
than those which he hath invented. Now some do impute this, to the
sharpness of his wit and understanding, which was a natural gift in
him: others do refer it to the extreme pains he took, which made these
things come so easily from him, that they seemed as if they had been
no trouble to him at all. For no man living of himself can devise
the demonstration of his propositions, what pains soever he take to
seek it: and yet straight so soon as he cometh to declare and open
it, every man then imagineth with himself he could have found it out
well enough, he can then so plainly make demonstration of the thing
he meaneth to show. And therefore that methinks is likely to be true,
which they write of him: that he was so ravished and drunk with the
sweet enticements of this siren, which as it were lay continually
with him, as he forgot his meat and drink, and was careless otherwise
of himself, that oftentimes his servants got him against his will
to the baths to wash and anoint him: and yet being there, he would
ever be drawing out of the geometrical figures, even in the very imbers
of the chimney. And while they were anointing of him with oils and
sweet savours, with his finger he did draw lines upon his naked body:
so far was he taken from himself, and brought into an ecstasy or trance,
with the delight he had in the study of geometry, and truly ravished
with the love of the Muses. But amongst many notable things he devised,
it appeareth, that he most esteemed the demonstration of the proportion
between the cylinder (to wit, the round column)\ and the sphere or
globe contained in the same: for he prayed his kinsmen and friends,
that after his death they would put a cylinder upon his tomb, containing
a massy sphere, with an inscription of the proportion, whereof the
continent exceedeth the thing contained.''%
\footnote{We quote the quaint old translation of North, printed in 1657.%
}
\end{quote}
{}

It should be observed that neither Polybius nor Plutarch mentions
the use of burning-glasses in connection with the siege of Syracuse,
nor indeed are these referred to by any other ancient writer of authority.
Nevertheless, a story gained credence down to a late day to the effect
that Archimedes had set fire to the fleet of the enemy with the aid
of concave mirrors. An experiment was made by Sir Isaac Newton to
show the possibility of a phenomenon so well in accord with the genius
of Archimedes, but the silence of all the early authorities makes
it more than doubtful whether any such expedient was really adopted.

It will be observed that the chief principle involved in all these
mechanisms was a capacity to transmit great power through levers and
pulleys, and this brings us to the most important field of the Syracusan
philosopher's activity. It was as a student of the lever and the pulley
that Archimedes was led to some of his greatest mechanical discoveries.
He is even credited with being the discoverer of the compound pulley.
More likely he was its developer only, since the principle of the
pulley was known to the old Babylonians, as their sculptures testify.
But there is no reason to doubt the general outlines of the story
that Archimedes astounded King \textit{\emph{Hiero}} by proving that,
with the aid of multiple pulleys, the strength of one man could suffice
to drag the largest ship from its moorings.

The property of the lever, from its fundamental principle, was studied
by him, beginning with the self-evident fact that {}``equal bodies
at the ends of the equal arms of a rod, supported on its middle point,
will balance each other''; or, what amounts to the same thing stated
in another way, a regular cylinder of uniform matter will balance
at its middle point. From this starting-point he elaborated the subject
on such clear and satisfactory principles that they stand to-day practically
unchanged and with few additions. From all his studies and experiments
he finally formulated the principle that {}``bodies will be \emph{in}
\textit{equilibrio} when their distance from the fulcrum or point
of support is inversely as their weight.'' He is credited with having
summed up his estimate of the capabilities of the lever with the well-known
expression, {}``Give me a fulcrum on which to rest or a place on
which to stand, and I will move the earth.''

But perhaps the feat of all others that most appealed to the imagination
of his contemporaries, and possibly also the one that had the greatest
bearing upon the position of Archimedes as a scientific discoverer,
was the one made familiar through the tale of the crown of \textit{\emph{Hiero}}.
This crown, so the story goes, was supposed to be made of solid gold,
but King \textit{\emph{Hiero}} for some reason suspected the honesty
of the jeweller, and desired to know if Archimedes could devise a
way of testing the question without injuring the crown. Greek imagination
seldom spoiled a story in the telling, and in this case the tale was
allowed to take on the most picturesque of phases. The philosopher,
we are assured, pondered the problem for a long time without succeeding,
but one day as he stepped into a bath, his attention was attracted
by the overflow of water. A new train of ideas was started in his
ever-receptive brain. Wild with enthusiasm he sprang from the bath,
and, forgetting his robe, dashed along the streets of Syracuse, shouting:
{}``Eureka! Eureka!''\ (I have found it!)\ The thought that had
come into his mind was this: That any heavy substance must have a
bulk proportionate to its weight; that gold and silver differ in weight,
bulk for bulk, and that the way to test the bulk of such an irregular
object as a crown was to immerse it in water. The experiment was made.
A lump of pure gold of the weight of the crown was immersed in a certain
receptacle filled with water, and the overflow noted. Then a lump
of pure silver of the same weight was similarly immersed; lastly the
crown itself was immersed, and of course---for the story must not
lack its dramatic sequel---was found bulkier than its weight of pure
gold. Thus the genius that could balk warriors and armies could also
foil the wiles of the silversmith.

Whatever the truth of this picturesque narrative, the fact remains
that some such experiments as these must have paved the way for perhaps
the greatest of all the studies of Archimedes---those that relate
to the buoyancy of water. Leaving the field of fable, we must now
examine these with some precision. Fortunately, the writings of Archimedes
himself are still extant, in which the results of his remarkable experiments
are related, so we may present the results in the words of the discoverer.

Here they are: {}``First: The surface of every coherent liquid in
a state of rest is spherical, and the centre of the sphere coincides
with the centre of the earth. Second: A solid body which, bulk for
bulk, is of the same weight as a liquid, if immersed in the liquid
will sink so that the surface of the body is even with the surface
of the liquid, but will not sink deeper. Third: Any solid body which
is lighter, bulk for bulk, than a liquid, if placed in the liquid
will sink so deep as to displace the mass of liquid equal in weight
to another body. Fourth: If a body which is lighter than a liquid
is forcibly immersed in the liquid, it will be pressed upward with
a force corresponding to the weight of a like volume of water, less
the weight of the body itself. Fifth: Solid bodies which, bulk for
bulk, are heavier than a liquid, when immersed in the liquid sink
to the bottom, but become in the liquid as much lighter as the weight
of the displaced water itself differs from the weight of the solid.''
These propositions are not difficult to demonstrate, once they are
conceived, but their discovery, combined with the discovery of the
laws of statics already referred to, may justly be considered as proving
Archimedes the most inventive experimenter of antiquity.

Curiously enough, the discovery which Archimedes himself is said to
have considered the most important of all his innovations is one that
seems much less striking. It is the answer to the question, What is
the relation in bulk between a sphere and its circumscribing cylinder?
Archimedes finds that the ratio is simply two to three. We are not
informed as to how he reached his conclusion, but an obvious method
would be to immerse a ball in a cylindrical cup. The experiment is
one which any one can make for himself, with approximate accuracy,
with the aid of a tumbler and a solid rubber ball or a billiard-ball
of just the right size. Another geometrical problem which Archimedes
solved was the problem as to the size of a triangle which has equal
area with a circle; the answer being, a triangle having for its base
the circumference of the circle and for its altitude the radius. Archimedes
solved also the problem of the relation of the diameter of the circle
to its circumference; his answer being a close approximation to the
familiar 3.1416, which every tyro in geometry will recall as the equivalent
of pi.

Numerous other of the studies of Archimedes having reference to conic
sections, properties of curves and spirals, and the like, are too
technical to be detailed here. The extent of his mathematical knowledge,
however, is suggested by the fact that he computed in great detail
the number of grains of sand that would be required to cover the sphere
of the sun's orbit, making certain hypothetical assumptions as to
the size of the earth and the distance of the sun for the purposes
of argument. Mathematicians find his computation peculiarly interesting
because it evidences a crude conception of the idea of logarithms.
From our present stand-point, the paper in which this calculation
is contained has considerable interest because of its assumptions
as to celestial mechanics. Thus Archimedes starts out with the preliminary
assumption that the circumference of the earth is less than three
million stadia. It must be understood that this assumption is purely
for the sake of argument. Archimedes expressly states that he takes
this number because it is {}``ten times as large as the earth has
been supposed to be by certain investigators.'' Here, perhaps, the
reference is to Eratosthenes, whose measurement of the earth we shall
have occasion to revert to in a moment. Continuing, Archimedes asserts
that the sun is larger than the earth, and the earth larger than the
moon. In this assumption, he says, he is following the opinion of
the majority of astronomers. In the third place, Archimedes assumes
that the diameter of the sun is not more than thirty times greater
than that of the moon. Here he is probably basing his argument upon
another set of measurements of Aristarchus, to which, also, we shall
presently refer more at length. In reality, his assumption is very
far from the truth, since the actual diameter of the sun, as we now
know, is something like four hundred times that of the moon. Fourth,
the circumference of the sun is greater than one side of the thousand-faced
figure inscribed in its orbit. The measurement, it is expressly stated,
is based on the measurements of Aristarchus, who makes the diameter
of the sun $\frac{1}{170}$ of its orbit. Archimedes adds, however,
that he himself has measured the angle and that it appears to him
to be less than $\frac{1}{64}$, and greater than $\frac{1}{200}$
part of the orbit. That is to say, reduced to modern terminology,
he places the limit of the sun's apparent size between thirty-three
minutes and twenty-seven minutes of arc. As the real diameter is thirty-two
minutes, this calculation is surprisingly exact, considering the implements
then at command. But the honor of first making it must be given to
Aristarchus and not to Archimedes.

We need not follow Archimedes to the limits of his incomprehensible
numbers of sand-grains. The calculation is chiefly remarkable because
it was made before the introduction of the so-called Arabic numerals
had simplified mathematical calculations. It will be recalled that
the Greeks used letters for numerals, and, having no cipher, they
soon found themselves in difficulties when large numbers were involved.
The Roman system of numerals simplified the matter somewhat, but the
beautiful simplicity of the decimal system did not come into vogue
until the Middle Ages, as we shall see. Notwithstanding the difficulties,
however, Archimedes followed out his calculations to the piling up
of bewildering numbers, which the modern mathematician finds to be
the consistent outcome of the problem he had set himself.

But it remains to notice the most interesting feature of this document
in which the calculation of the sand-grains is contained. {}``It
was known to me,''\ says Archimedes, {}``that most astronomers
understand by the expression `world'\ (universe)\ a ball of which
the centre is the middle point of the earth, and of which the radius
is a straight line between the centre of the earth and the sun.''
Archimedes himself appears to accept this opinion of the majority,---it
at least serves as well as the contrary hypothesis for the purpose
of his calculation,---but he goes on to say: {}``Aristarchus of Samos,
in his writing against the astronomers, seeks to establish the fact
that the world is really very different from this. He holds the opinion
that the fixed stars and the sun are immovable and that the earth
revolves in a circular line about the sun, the sun being at the centre
of this circle.'' This remarkable bit of testimony establishes beyond
question the position of Aristarchus of Samos as the Copernicus of
antiquity. We must make further inquiry as to the teachings of the
man who had gained such a remarkable insight into the true system
of the heavens.


\section*{\raggedright ARISTARCHUS OF SAMOS, THE COPERNICUS OF ANTIQUITY}

\addcontentsline{toc}{section}{ARISTARCHUS OF SAMOS, THE\\
COPERNICUS OF ANTIQUITY}

It appears that Aristarchus was a contemporary of Archimedes, but
the exact dates of his life are not known. He was actively engaged
in making astronomical observations in Samos somewhat before the middle
of the third century B.C.; in other words, just at the time when the
activities of the Alexandrian school were at their height. Hipparchus,
at a later day, was enabled to compare his own observations with those
made by Aristarchus, and, as we have just seen, his work was well
known to so distant a contemporary as Archimedes. Yet the facts of
his life are almost a blank for us, and of his writings only a single
one has been preserved. That one, however, is a most important and
interesting paper on the measurements of the sun and the moon. Unfortunately,
this paper gives us no direct clew as to the opinions of Aristarchus
concerning the relative positions of the earth and sun. But the testimony
of Archimedes as to this is unequivocal, and this testimony is supported
by other rumors in themselves less authoritative.

In contemplating this astronomer of Samos, then, we are in the presence
of a man who had solved in its essentials the problem of the mechanism
of the solar system. It appears from the words of Archimedes that
Aristarchus had propounded his theory in explicit writings. Unquestionably,
then, he held to it as a positive doctrine, not as a mere vague guess.
We shall show, in a moment, on what grounds he based his opinion.
Had his teaching found vogue, the story of science would be very different
from what it is. We should then have no tale to tell of a Copernicus
coming upon the scene fully seventeen hundred years later with the
revolutionary doctrine that our world is not the centre of the universe.
We should not have to tell of the persecution of a Bruno or of a Galileo
for teaching this doctrine in the seventeenth century of an era which
did not begin till two hundred years after the death of Aristarchus.
But, as we know, the teaching of the astronomer of Samos did not win
its way. The old conservative geocentric doctrine, seemingly so much
more in accordance with the every-day observations of mankind, supported
by the majority of astronomers with the Peripatetic philosophers at
their head, held its place. It found fresh supporters presently among
the later Alexandrians, and so fully eclipsed the heliocentric view
that we should scarcely know that view had even found an advocate
were it not for here and there such a chance record as the phrases
we have just quoted from Archimedes. Yet, as we now see, the heliocentric
doctrine, which we know to be true, had been thought out and advocated
as the correct theory of celestial mechanics by at least one worker
of the third century B.C. Such an idea, we may be sure, did not spring
into the mind of its originator except as the culmination of a long
series of observations and inferences. The precise character of the
evolution we perhaps cannot trace, but its broader outlines are open
to our observation, and we may not leave so important a topic without
at least briefly noting them.

Fully to understand the theory of Aristarchus, we must go back a century
or two and recall that as long ago as the time of that other great
native of Samos, Pythagoras, the conception had been reached that
the earth is in motion. We saw, in dealing with Pythagoras, that we
could not be sure as to precisely what he himself taught, but there
is no question that the idea of the world's motion became from an
early day a so-called Pythagorean doctrine. While all the other philosophers,
so far as we know, still believed that the world was flat, the Pythagoreans
out in Italy taught that the world is a sphere and that the apparent
motions of the heavenly bodies are really due to the actual motion
of the earth itself. They did not, however, vault to the conclusion
that this true motion of the earth takes place in the form of a circuit
about the sun. Instead of that, they conceived the central body of
the universe to be a great fire, invisible from the earth, because
the inhabited side of the terrestrial ball was turned away from it.
The sun, it was held, is but a great mirror, which reflects the light
from the central fire. Sun and earth alike revolve about this great
fire, each in its own orbit. Between the earth and the central fire
there was, curiously enough, supposed to be an invisible earthlike
body which was given the name of Anticthon, or counter-earth. This
body, itself revolving about the central fire, was supposed to shut
off the central light now and again from the sun or from the moon,
and thus to account for certain eclipses for which the shadow of the
earth did not seem responsible. It was, perhaps, largely to account
for such eclipses that the counter-earth was invented. But it is supposed
that there was another reason. The Pythagoreans held that there is
a peculiar sacredness in the number ten. Just as the Babylonians of
the early day and the Hegelian philosophers of a more recent epoch
saw a sacred connection between the number seven and the number of
planetary bodies, so the Pythagoreans thought that the universe must
be arranged in accordance with the number ten. Their count of the
heavenly bodies, including the sphere of the fixed stars, seemed to
show nine, and the counter-earth supplied the missing body.

The precise genesis and development of this idea cannot now be followed,
but that it was prevalent about the fifth century B.C. as a Pythagorean
doctrine cannot be questioned. Anaxagoras also is said to have taken
account of the hypothetical counter-earth in his explanation of eclipses;
though, as we have seen, he probably did not accept that part of the
doctrine which held the earth to be a sphere. The names of Philolaus
and Heraclides have been linked with certain of these Pythagorean
doctrines. Eudoxus, too, who, like the others, lived in Asia Minor
in the fourth century B.C., was held to have made special studies
of the heavenly spheres and perhaps to have taught that the earth
moves. So, too, Nicetas must be named among those whom rumor credited
with having taught that the world is in motion. In a word, the evidence,
so far as we can garner it from the remaining fragments, tends to
show that all along, from the time of the early Pythagoreans, there
had been an undercurrent of opinion in the philosophical world which
questioned the fixity of the earth; and it would seem that the school
of thinkers who tended to accept the revolutionary view centred in
Asia Minor, not far from the early home of the founder of the Pythagorean
doctrines. It was not strange, then, that the man who was finally
to carry these new opinions to their logical conclusion should hail
from Samos.

But what was the support which observation could give to this new,
strange conception that the heavenly bodies do not in reality move
as they seem to move, but that their apparent motion is due to the
actual revolution of the earth? It is extremely difficult for any
one nowadays to put himself in a mental position to answer this question.
We are so accustomed to conceive the solar system as we know it to
be, that we are wont to forget how very different it is from what
it seems. Yet one needs but to glance up at the sky, and then to glance
about one at the solid earth, to grant, on a moment's reflection,
that the geocentric idea is of all others the most natural; and that
to conceive the sun as the actual centre of the solar system is an
idea which must look for support to some other evidence than that
which ordinary observation can give. Such was the view of most of
the ancient philosophers, and such continued to be the opinion of
the majority of mankind long after the time of Copernicus. We must
not forget that even so great an observing astronomer as Tycho Brahe,
so late as the seventeenth century, declined to accept the heliocentric
theory, though admitting that all the planets except the earth revolve
about the sun. We shall see that before the Alexandrian school lost
its influence a geocentric scheme had been evolved which fully explained
all the apparent motions of the heavenly bodies. All this, then, makes
us but wonder the more that the genius of an Aristarchus could give
precedence to scientific induction as against the seemingly clear
evidence of the senses.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S218}\end{center}

\noindent \begin{center}\noun{\small Diagram to Illustrate Aristarchus'
Measurement of the Relative Distances from the Earth of the Moon and
the Sun}\end{center}{\small \par}

\noindent \emph{\footnotesize (For explanation of the diagram, refer
to the body of the text.) }
\end{figure}
What, then, was the line of scientific induction that led Aristarchus
to this wonderful goal? Fortunately, we are able to answer that query,
at least in part. Aristarchus gained his evidence through some wonderful
measurements. First, he measured the disks of the sun and the moon.
This, of course, could in itself give him no clew to the distance
of these bodies, and therefore no clew as to their relative size;
but in attempting to obtain such a clew he hit upon a wonderful yet
altogether simple experiment. It occurred to him that when the moon
is precisely dichotomized---that is to say, precisely at the half---the
line of vision from the earth to the moon must be precisely at right
angles with the line of light passing from the sun to the moon. At
this moment, then, the imaginary lines joining the sun, the moon,
and the earth, make a right angle triangle. But the properties of
the right-angle triangle had long been studied and were well understood.
One acute angle of such a triangle determines the figure of the triangle
itself. We have already seen that Thales, the very earliest of the
Greek philosophers, measured the distance of a ship at sea by the
application of this principle. Now Aristarchus sights the sun in place
of Thales' ship, and, sighting the moon at the same time, measures
the angle and establishes the shape of his right-angle triangle. This
does not tell him the distance of the sun, to be sure, for he does
not know the length of his base-line---that is to say, of the line
between the moon and the earth. But it does establish the relation
of that base-line to the other lines of the triangle; in other words,
it tells him the distance of the sun in terms of the moon's distance.
As Aristarchus strikes the angle, it shows that the sun is eighteen
times as distant as the moon. Now, by comparing the apparent size
of the sun with the apparent size of the moon---which, as we have
seen, Aristarchus has already measured---he is able to tell us that,
the sun is {}``more than 5832 times, and less than 8000''\ times
larger than the moon; though his measurements, taken by themselves,
give no clew to the actual bulk of either body. These conclusions,
be it understood, are absolutely valid inferences---nay, demonstrations---from
the measurements involved, provided only that these measurements have
been correct. Unfortunately, the angle of the triangle we have just
seen measured is exceedingly difficult to determine with accuracy,
while at the same time, as a moment's reflection will show, it is
so large an angle that a very slight deviation from the truth will
greatly affect the distance at which its line joins the other side
of the triangle. Then again, it is virtually impossible to tell the
precise moment when the moon is at half, as the line it gives is not
so sharp that we can fix it with absolute accuracy. There is, moreover,
another element of error due to the refraction of light by the earth's
atmosphere. The experiment was probably made when the sun was near
the horizon, at which time, as we now know, but as Aristarchus probably
did not suspect, the apparent displacement of the sun's position is
considerable; and this displacement, it will be observed, is in the
direction to lessen the angle in question.

In point of fact, Aristarchus estimated the angle at eighty-seven
degrees. Had his instrument been more precise, and had he been able
to take account of all the elements of error, he would have found
it eighty-seven degrees and fifty-two minutes. The difference of measurement
seems slight; but it sufficed to make the computations differ absurdly
from the truth. The sun is really not merely eighteen times but more
than two hundred times the distance of the moon, as Wendelein discovered
on repeating the experiment of Aristarchus about two thousand years
later. Yet this discrepancy does not in the least take away from the
validity of the method which Aristarchus employed. Moreover, his conclusion,
stated in general terms, was perfectly correct: the sun is many times
more distant than the moon and vastly larger than that body. Granted,
then, that the moon is, as Aristarchus correctly believed, considerably
less in size than the earth, the sun must be enormously larger than
the earth; and this is the vital inference which, more than any other,
must have seemed to Aristarchus to confirm the suspicion that the
sun and not the earth is the centre of the planetary system. It seemed
to him inherently improbable that an enormously large body like the
sun should revolve about a small one such as the earth. And again,
it seemed inconceivable that a body so distant as the sun should whirl
through space so rapidly as to make the circuit of its orbit in twenty-four
hours. But, on the other hand, that a small body like the earth should
revolve about the gigantic sun seemed inherently probable. This proposition
granted, the rotation of the earth on its axis follows as a necessary
consequence in explanation of the seeming motion of the stars. Here,
then, was the heliocentric doctrine reduced to a virtual demonstration
by Aristarchus of Samos, somewhere about the middle of the third century
B.C.

It must be understood that in following out the, steps of reasoning
by which we suppose Aristarchus to have reached so remarkable a conclusion,
we have to some extent guessed at the processes of thought-development;
for no line of explication written by the astronomer himself on this
particular point has come down to us. There does exist, however, as
we have already stated, a very remarkable treatise by Aristarchus
on the \emph{Size and Distance of the Sun and the Moon}, which so
clearly suggests the methods of reasoning of the great astronomer,
and so explicitly cites the results of his measurements, that we cannot
well pass it by without quoting from it at some length. It is certainly
one of the most remarkable scientific documents of antiquity. As already
noted, the heliocentric doctrine is not expressly stated here. It
seems to be tacitly implied throughout, but it is not a necessary
consequence of any of the propositions expressly stated. These propositions
have to do with certain observations and measurements and what Aristarchus
believes to be inevitable deductions from them, and he perhaps did
not wish to have these deductions challenged through associating them
with a theory which his contemporaries did not accept. In a word,
the paper of Aristarchus is a rigidly scientific document unvitiated
by association with any theorizings that are not directly germane
to its central theme. The treatise opens with certain hypotheses as
follows:\ 

\begin{quotation}
{}``First. The moon receives its light from the sun.

{}``Second. The earth may be considered as a point and as the centre
of the orbit of the moon.

{}``Third. When the moon appears to us dichotomized it offers to
our view a great circle {[}or actual meridian{]}\ of its circumference
which divides the illuminated part from the dark part.

{}``Fourth. When the moon appears dichotomized its distance from
the sun is less than a quarter of the circumference {[}of its orbit{]}\ by
a thirtieth part of that quarter.''
\end{quotation}
{}

That is to say, in modern terminology, the moon at this time lacks
three degrees (one thirtieth of ninety degrees)\ of being at right
angles with the line of the sun as viewed from the earth; or, stated
otherwise, the angular distance of the moon from the sun as viewed
from the earth is at this time eighty-seven degrees---this being,
as we have already observed, the fundamental measurement upon which
so much depends. We may fairly suppose that some previous paper of
Aristarchus's has detailed the measurement which here is taken for
granted, yet which of course could depend solely on observation.

\begin{quotation}
{}``Fifth. The diameter of the shadow {[}cast by the earth at the
point where the moon's orbit cuts that shadow when the moon is eclipsed{]}\ is
double the diameter of the moon.''
\end{quotation}
{}

Here again a knowledge of previously established measurements is taken
for granted; but, indeed, this is the case throughout the treatise.

\begin{quotation}
{}``Sixth. The arc subtended in the sky by the moon is a fifteenth
part of a sign''\ {[}of the zodiac; that is to say, since there
are twenty-four, signs in the zodiac, one-fifteenth of one twenty-fourth,
or in modern terminology, one degree of arc. This is Aristarchus's
measurement of the moon to which we have already referred when speaking
of the measurements of Archimedes.{]}

{}``If we admit these six hypotheses,''\ Aristarchus continues,
{}``it follows that the sun is more than eighteen times more distant
from the earth than is the moon, and that it is less than twenty times
more distant, and that the diameter of the sun bears a corresponding
relation to the diameter of the moon; which is proved by the position
of the moon when dichotomized. But the ratio of the diameter of the
sun to that of the earth is greater than nineteen to three and less
than forty-three to six. This is demonstrated by the relation of the
distances, by the position {[}of the moon{]}\ in relation to the
earth's shadow, and by the fact that the arc subtended by the moon
is a fifteenth part of a sign.''
\end{quotation}
{}

Aristarchus follows with nineteen propositions intended to elucidate
his hypotheses and to demonstrate his various contentions. These show
a singularly clear grasp of geometrical problems and an altogether
correct conception of the general relations as to size and position
of the earth, the moon, and the sun. His reasoning has to do largely
with the shadow cast by the earth and by the moon, and it presupposes
a considerable knowledge of the phenomena of eclipses. His first proposition
is that {}``two equal spheres may always be circumscribed in a cylinder;
two unequal spheres in a cone of which the apex is found on the side
of the smaller sphere; and a straight line joining the centres of
these spheres is perpendicular to each of the two circles made by
the contact of the surface of the cylinder or of the cone with the
spheres.''

It will be observed that Aristarchus has in mind here the moon, the
earth, and the sun as spheres to be circumscribed within a cone, which
cone is made tangible and measurable by the shadows cast by the non-luminous
bodies; since, continuing, he clearly states in proposition nine,
that {}``when the sun is totally eclipsed, an observer on the earth's
surface is at an apex of a cone comprising the moon and the sun.''
Various propositions deal with other relations of the shadows which
need not detain us since they are not fundamentally important, and
we may pass to the final conclusions of Aristarchus, as reached in
his propositions ten to nineteen.

Now, since (proposition ten)\ {}``the diameter of the sun is more
than eighteen times and less than twenty times greater than that of
the moon,''\ it follows (proposition eleven)\ {}``that the bulk
of the sun is to that of the moon in ratio, greater than 5832 to 1,
and less than 8000 to 1.''

\begin{quotation}
{}``Proposition sixteen. The diameter of the sun is to the diameter
of the earth in greater proportion than nineteen to three, and less
than forty-three to six.

{}``Proposition seventeen. The bulk of the sun is to that of the
earth in greater proportion than 6859 to 27, and less than 79,507
to 216.

{}``Proposition eighteen. The diameter of the earth is to the diameter
of the moon in greater proportion than 108 to 43 and less than 60
to 19.

{}``Proposition nineteen. The bulk of the earth is to that of the
moon in greater proportion than 1,259,712 to 79,507 and less than
20,000 to 6859.''
\end{quotation}
{}

Such then are the more important conclusions of this very remarkable
paper---a paper which seems to have interest to the successors of
Aristarchus generation after generation, since this alone of all the
writings of the great astronomer has been preserved. How widely the
exact results of the measurements of Aristarchus, differ from the
truth, we have pointed out as we progressed. But let it be repeated
that this detracts little from the credit of the astronomer who had
such clear and correct conceptions of the relations of the heavenly
bodies and who invented such correct methods of measurement. Let it
be particularly observed, however, that all the conclusions of Aristarchus
are stated in relative terms. He nowhere attempts to estimate the
precise size of the earth, of the moon, or of the sun, or the actual
distance of one of these bodies from another. The obvious reason for
this is that no data were at hand from which to make such precise
measurements. Had Aristarchus known the size of any one of the bodies
in question, he might readily, of course, have determined the size
of the others by the mere application of his relative scale; but he
had no means of determining the size of the earth, and to this extent
his system of measurements remained imperfect. Where Aristarchus halted,
however, another worker of the same period took the task in hand and
by an altogether wonderful measurement determined the size of the
earth, and thus brought the scientific theories of cosmology to their
climax. This worthy supplementor of the work of Aristarchus was Eratosthenes
of Alexandria.


\section*{\raggedright ERATOSTHENES, {}``THE SURVEYOR OF THE WORLD''}

\addcontentsline{toc}{section}{ERATOSTHENES, {}``THE SURVEYOR\\
OF THE WORLD''}

An altogether remarkable man was this native of Cyrene, who came to
Alexandria from Athens to be the chief librarian of Ptolemy Euergetes.
He was not merely an astronomer and a geographer, but a poet and grammarian
as well. His contemporaries jestingly called him Beta (the Second),
because he was said through the universality of his attainments to
be {}``a second Plato''\ in philosophy, {}``a second Thales''\ in
astronomy, and so on throughout the list. He was also called the {}``surveyor
of the world,''\ in recognition of his services to geography. Hipparchus
said of him, perhaps half jestingly, that he had studied astronomy
as a geographer and geography as an astronomer. It is not quite clear
whether the epigram was meant as compliment or as criticism. Similar
phrases have been turned against men of versatile talent in every
age. Be that as it may, Eratosthenes passed into history as the father
of scientific geography and of scientific chronology; as the astronomer
who first measured the obliquity of the ecliptic; and as the inventive
genius who performed the astounding feat of measuring the size of
the globe on which we live at a time when only a relatively small
portion of that globe's surface was known to civilized man. It is
no discredit to approach astronomy as a geographer and geography as
an astronomer if the results are such as these. What Eratosthenes
really did was to approach both astronomy and geography from two seemingly
divergent points of attack---namely, from the stand-point of the geometer
and also from that of the poet. Perhaps no man in any age has brought
a better combination of observing and imaginative faculties to the
aid of science.

Nearly all the discoveries of Eratosthenes are associated with observations
of the shadows cast by the sun. We have seen that, in the study of
the heavenly bodies, much depends on the measurement of angles. Now
the easiest way in which angles can be measured, when solar angles
are in question, is to pay attention, not to the sun itself, but to
the shadow that it casts. We saw that Thales made some remarkable
measurements with the aid of shadows, and we have more than once referred
to the gnomon, which is the most primitive, but which long remained
the most important, of astronomical instruments. It is believed that
Eratosthenes invented an important modification of the gnomon which
was elaborated afterwards by Hipparchus and called an armillary sphere.
This consists essentially of a small gnomon, or perpendicular post,
attached to a plane representing the earth's equator and a hemisphere
in imitation of the earth's surface. With the aid of this, the shadow
cast by the sun could be very accurately measured. It involves no
new principle. Every perpendicular post or object of any kind placed
in the sunlight casts a shadow from which the angles now in question
could be roughly measured. The province of the armillary sphere was
to make these measurements extremely accurate.

With the aid of this implement, Eratosthenes carefully noted the longest
and the shortest shadows cast by the gnomon---that is to say, the
shadows cast on the days of the \textit{\emph{solstices}}. He found
that the distance between the tropics thus measured represented 47$^\circ$
42'\ 39''\ of arc. One-half of this, or 23$^\circ$ 51' 19.5'',
represented the obliquity of the ecliptic---that is to say, the angle
by which the earth's axis dipped from the perpendicular with reference
to its orbit. This was a most important observation, and because of
its accuracy it has served modern astronomers well for comparison
in measuring the trifling change due to our earth's slow, swinging
wobble. For the earth, be it understood, like a great top spinning
through space, holds its position with relative but not quite absolute
fixity. It must not be supposed, however, that the experiment in question
was quite new with Eratosthenes. His merit consists rather in the
accuracy with which he made his observation than in the novelty of
the conception; for it is recorded that Eudoxus, a full century earlier,
had remarked the obliquity of the ecliptic. That observer had said
that the obliquity corresponded to the side of a pentadecagon, or
fifteen-sided figure, which is equivalent in modern phraseology to
twenty-four degrees of arc. But so little is known regarding the way
in which Eudoxus reached his estimate that the measurement of Eratosthenes
is usually spoken of as if it were the first effort of the kind.

Much more striking, at least in its appeal to the popular imagination,
was that other great feat which Eratosthenes performed with the aid
of his perfected gnomon---the measurement of the earth itself. When
we reflect that at this period the portion of the earth open to observation
extended only from the Straits of Gibraltar on the west to India on
the east, and from the North Sea to Upper Egypt, it certainly seems
enigmatical---at first thought almost miraculous---that an observer
should have been able to measure the entire globe. That he should
have accomplished this through observation of nothing more than a
tiny bit of Egyptian territory and a glimpse of the sun's shadow makes
it seem but the more wonderful. Yet the method of Eratosthenes, like
many another enigma, seems simple enough once it is explained. It
required but the application of a very elementary knowledge of the
geometry of circles, combined with the use of a fact or two from local
geography---which detracts nothing from the genius of the man who
could reason from such simple premises to so wonderful a conclusion.

Stated in a few words, the experiment of Eratosthenes was this. His
geographical studies had taught him that the town of Syene lay directly
south of Alexandria, or, as we should say, on the same meridian of
latitude. He had learned, further, that Syene lay directly under the
tropic, since it was reported that at noon on the day of the summer
solstice the gnomon there cast no shadow, while a deep well was illumined
to the bottom by the sun. A third item of knowledge, supplied by the
surveyors of Ptolemy, made the distance between Syene and Alexandria
five thousand stadia. These, then, were the preliminary data required
by Eratosthenes. Their significance consists in the fact that here
is a measured bit of the earth's arc five thousand stadia in length.
If we could find out what angle that bit of arc subtends, a mere matter
of multiplication would give us the size of the earth. But how determine
this all-important number? The answer came through reflection on the
relations of concentric circles. If you draw any number of circles,
of whatever size, about a given centre, a pair of radii drawn from
that centre will cut arcs of the same relative size from all the circles.
One circle may be so small that the actual arc subtended by the radii
in a given case may be but an inch in length, while another circle
is so large that its corresponding are is measured in millions of
miles; but in each case the same number of so-called degrees will
represent the relation of each arc to its circumference. Now, Eratosthenes
knew, as just stated, that the sun, when on the meridian on the day
of the summer solstice, was directly over the town of Syene. This
meant that at that moment a radius of the earth projected from Syene
would point directly towards the sun. Meanwhile, of course, the zenith
would represent the projection of the radius of the earth passing
through Alexandria. All that was required, then, was to measure, at
Alexandria, the angular distance of the sun from the zenith at noon
on the day of the solstice to secure an approximate measurement of
the arc of the sun's circumference, corresponding to the arc of the
earth's surface represented by the measured distance between Alexandria
and Syene.

The reader will observe that the measurement could not be absolutely
accurate, because it is made from the surface of the earth, and not
from the earth's centre, but the size of the earth is so insignificant
in comparison with the distance of the sun that this slight discrepancy
could be disregarded.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth,
  height=0.50\paperwidth,
  keepaspectratio]{1hsci10-Wil1S230}\end{center}

\noindent \begin{center}\noun{\small Diagram to Illustrate Eratosthenes'
Measurement of the Globe}\end{center}{\small \par}

\emph{\footnotesize FIG. 1. AF is a gnomon at Alexandria; SB a gnomon
at Syene; IS and JK represent the sun's rays. The angle actually measured
by Eratosthenes is KFA, as determined by the shadow cast by the gnomon
AF. This angle is equal to the opposite angle JFL, which measures
the sun's distance from the zenith; and which is also equal to the
angle AES -- to determine the size of which is the real object of
the entire measurement. }{\footnotesize \par}

\emph{\footnotesize FIG. 2 shows the form of the gnomon actually employed
in antiquity. The hemisphere KA being marked with a scale, it is obvious
that in actual practice Eratosthenes required only to set his gnomon
in the sunlight at the proper moment, and read off the answer to his
problem at a glance. The simplicity of the method makes the result
seem all the more wonderful. }
\end{figure}
The way in which Eratosthenes measured this angle was very simple.
He merely measured the angle of the shadow which his perpendicular
gnomon at Alexandria cast at mid-day on the day of the solstice, when,
as already noted, the sun was directly perpendicular at Syene. Now
a glance at the diagram will make it clear that the measurement of
this angle of the shadow is merely a convenient means of determining
the precisely equal opposite angle subtending an arc of an imaginary
circle passing through the sun; the arc which, as already explained,
corresponds with the arc of the earth's surface represented by the
distance between Alexandria and Syene. He found this angle to represent
7$^\circ$ 12', or one-fiftieth of the circle. Five thousand stadia,
then, represent one-fiftieth of the earth's circumference; the entire
circumference being, therefore, 250,000 stadia. Unfortunately, we
do not know which one of the various measurements used in antiquity
is represented by the stadia of Eratosthenes. According to the researches
of Lepsius, however, the stadium in question represented 180 meters,
and this would make the earth, according to the measurement of Eratosthenes,
about twenty-eight thousand miles in circumference, an answer sufficiently
exact to justify the wonder which the experiment excited in antiquity,
and the admiration with which it has ever since been regarded.

Of course it is the method, and not its details or its exact results,
that excites our interest. And beyond question the method was an admirable
one. Its result, however, could not have been absolutely accurate,
because, while correct in principle, its data were defective. In point
of fact Syene did not lie precisely on the same meridian as Alexandria,
neither did it lie exactly on the tropic. Here, then, are two elements
of inaccuracy. Moreover, it is doubtful whether Eratosthenes made
allowance, as he should have done, for the semi-diameter of the sun
in measuring the angle of the shadow. But these are mere details,
scarcely worthy of mention from our present stand-point. What perhaps
is deserving of more attention is the fact that this epoch-making
measurement of Eratosthenes may not have been the first one to be
made. A passage of Aristotle records that the size of the earth was
said to be 400,000 stadia. Some commentators have thought that Aristotle
merely referred to the area of the inhabited portion of the earth
and not to the circumference of the earth itself, but his words seem
doubtfully susceptible of this interpretation; and if he meant, as
his words seem to imply, that philosophers of his day had a tolerably
precise idea of the globe, we must assume that this idea was based
upon some sort of measurement. The recorded size, 400,000 stadia,
is a sufficient approximation to the truth to suggest something more
than a mere unsupported guess. Now, since Aristotle died more than
fifty years before Eratosthenes was born, his report as to the alleged
size of the earth certainly has a suggestiveness that cannot be overlooked;
but it arouses speculations without giving an inkling as to their
solution. If Eratosthenes had a precursor as an earth-measurer, no
hint or rumor has come down to us that would enable us to guess who
that precursor may have been. His personality is as deeply enveloped
in the mists of the past as are the personalities of the great prehistoric
discoverers. For the purpose of the historian, Eratosthenes must stand
as the inventor of the method with which his name is associated, and
as the first man of whom we can say with certainty that he measured
the size of the earth. Right worthily, then, had the Alexandrian philosopher
won his proud title of {}``surveyor of the world.''


\section*{\raggedright HIPPARCHUS, {}``THE LOVER OF TRUTH''}

\addcontentsline{toc}{section}{HIPPARCHUS, {}``THE LOVER OF\\
TRUTH''}

Eratosthenes outlived most of his great contemporaries. He saw the
turning of that first and greatest century of Alexandrian science,
the third century before our era. He died in the year 196 B.C., having,
it is said, starved himself to death to escape the miseries of blindness;---to
the measurer of shadows, life without light seemed not worth the living.
Eratosthenes left no immediate successor. A generation later, however,
another great figure appeared in the astronomical world in the person
of Hipparchus, a man who, as a technical observer, had perhaps no
peer in the ancient world: one who set so high a value upon accuracy
of observation as to earn the title of {}``the lover of truth.''
Hipparchus was born at Nic\ae{}a, in Bithynia, in the year 160 B.C.
His life, all too short for the interests of science, ended in the
year 125 B.C. The observations of the great astronomer were made chiefly,
perhaps entirely, at Rhodes. A misinterpretation of Ptolemy's writings
led to the idea that Hipparchus, performed his chief labors in Alexandria,
but it is now admitted that there is no evidence for this. Delambre
doubted, and most subsequent writers follow him here, whether Hipparchus
ever so much as visited Alexandria. In any event there seems to be
no question that Rhodes may claim the honor of being the chief site
of his activities.

It was Hipparchus whose somewhat equivocal comment on the work of
Eratosthenes we have already noted. No counter-charge in kind could
be made against the critic himself; he was an astronomer pure and
simple. His gift was the gift of accurate observation rather than
the gift of imagination. No scientific progress is possible without
scientific guessing, but Hipparchus belonged to that class of observers
with whom hypothesis is held rigidly subservient to fact. It was not
to be expected that his mind would be attracted by the heliocentric
theory of Aristarchus. He used the facts and observations gathered
by his great predecessor of Samos, but he declined to accept his theories.
For him the world was central; his problem was to explain, if he could,
the irregularities of motion which sun, moon, and planets showed in
their seeming circuits about the earth. Hipparchus had the gnomon
of Eratosthenes---doubtless in a perfected form---to aid him, and
he soon proved himself a master in its use. For him, as we have said,
accuracy was everything; this was the one element that led to all
his great successes.

Perhaps his greatest feat was to demonstrate the eccentricity of the
sun's seeming orbit. We of to-day, thanks to Keppler and his followers,
know that the earth and the other planetary bodies in their circuit
about the sun describe an ellipse and not a circle. But in the day
of Hipparchus, though the ellipse was recognized as a geometrical
figure (it had been described and named along with the parabola and
hyperbola by \textit{\emph{Apollonius}} of Perga, the pupil of Euclid),
yet it would have been the rankest heresy to suggest an elliptical
course for any heavenly body. A metaphysical theory, as propounded
perhaps by the Pythagoreans but ardently supported by Aristotle, declared
that the circle is the perfect figure, and pronounced it inconceivable
that the motions of the spheres should be other than circular. This
thought dominated the mind of Hipparchus, and so when his careful
measurements led him to the discovery that the northward and southward
journeyings of the sun did not divide the year into four equal parts,
there was nothing open to him but to either assume that the earth
does not lie precisely at the centre of the sun's circular orbit or
to find some alternative hypothesis.

In point of fact, the sun (reversing the point of view in accordance
with modern discoveries)\ does lie at one focus of the earth's elliptical
orbit, and therefore away from the physical centre of that orbit;
in other words, the observations of Hipparchus were absolutely accurate.
He was quite correct in finding that the sun spends more time on one
side of the equator than on the other. When, therefore, he estimated
the relative distance of the earth from the geometrical centre of
the sun's supposed circular orbit, and spoke of this as the measure
of the sun's eccentricity, he propounded a theory in which true data
of observation were curiously mingled with a positively inverted theory.
That the theory of Hipparchus was absolutely consistent with all the
facts of this particular observation is the best evidence that could
be given of the difficulties that stood in the way of a true explanation
of the mechanism of the heavens.

But it is not merely the sun which was observed to vary in the speed
of its orbital progress; the moon and the planets also show curious
accelerations and retardations of motion. The moon in particular received
most careful attention from Hipparchus. Dominated by his conception
of the perfect spheres, he could find but one explanation of the anomalous
motions which he observed, and this was to assume that the various
heavenly bodies do not fly on in an unvarying arc in their circuit
about the earth, but describe minor circles as they go which can be
likened to nothing so tangibly as to a light attached to the rim of
a wagon-wheel in motion. If such an invisible wheel be imagined as
carrying the sun, for example, on its rim, while its invisible hub
follows unswervingly the circle of the sun's mean orbit (this wheel,
be it understood, lying in the plane of the orbit, not at right-angles
to it), then it must be obvious that while the hub remains always
at the same distance from the earth, the circling rim will carry the
sun nearer the earth, then farther away, and that while it is traversing
that portion of the are which brings it towards the earth, the actual
forward progress of the sun will be retarded notwithstanding the uniform
motion of the hub, just as it will be accelerated in the opposite
arc. Now, if we suppose our sun-bearing wheel to turn so slowly that
the sun revolves but once about its imaginary hub while the wheel
itself is making the entire circuit of the orbit, we shall have accounted
for the observed fact that the sun passes more quickly through one-half
of the orbit than through the other. Moreover, if we can visualize
the process and imagine the sun to have left a visible line of fire
behind him throughout the course, we shall see that in reality the
two circular motions involved have really resulted in producing an
elliptical orbit.

The idea is perhaps made clearer if we picture the actual progress
of the lantern attached to the rim of an ordinary cart-wheel. When
the cart is drawn forward the lantern is made to revolve in a circle
as regards the hub of the wheel, but since that hub is constantly
going forward, the actual path described by the lantern is not a circle
at all but a waving line. It is precisely the same with the imagined
course of the sun in its orbit, only that we view these lines just
as we should view the lantern on the wheel if we looked at it from
directly above and not from the side. The proof that the sun is describing
this waving line, and therefore must be considered as attached to
an imaginary wheel, is furnished, as it seemed to Hipparchus, by the
observed fact of the sun's varying speed.

That is one way of looking at the matter. It is an hypothesis that
explains the observed facts---after a fashion, and indeed a very remarkable
fashion. The idea of such an explanation did not originate with Hipparchus.
The germs of the thought were as old as the Pythagorean doctrine that
the earth revolves about a centre that we cannot see. Eudoxus gave
the conception greater tangibility, and may be considered as the father
of this doctrine of wheels---epicycles, as they came to be called.
Two centuries before the time of Hipparchus he conceived a doctrine
of spheres which Aristotle found most interesting, and which served
to explain, along the lines we have just followed, the observed motions
of the heavenly bodies. Calippus, the reformer of the calendar, is
said to have carried an account of this theory to Aristotle. As new
irregularities of motion of the sun, moon, and planetary bodies were
pointed out, new epicycles were invented. There is no limit to the
number of imaginary circles that may be inscribed about an imaginary
centre, and if we conceive each one of these circles to have a proper
motion of its own, and each one to carry the sun in the line of that
motion, except as it is diverted by the other motions---if we can
visualize this complex mingling of wheels---we shall certainly be
able to imagine the heavenly body which lies at the juncture of all
the rims, as being carried forward in as erratic and wobbly a manner
as could be desired. In other words, the theory of epicycles will
account for all the facts of the observed motions of all the heavenly
bodies, but in so doing it fills the universe with a most bewildering
network of intersecting circles. Even in the time of Calippus fifty-five
of these spheres were computed.

We may well believe that the clear-seeing Aristarchus would look askance
at such a complex system of imaginary machinery. But Hipparchus, pre-eminently
an observer rather than a theorizer, seems to have been content to
accept the theory of epicycles as he found it, though his studies
added to its complexities; and Hipparchus was the dominant scientific
personality of his century. What he believed became as a law to his
immediate successors. His tenets were accepted as final by their great
popularizer, Ptolemy, three centuries later; and so the heliocentric
theory of Aristarchus passed under a cloud almost at the hour of its
dawning, there to remain obscured and forgotten for the long lapse
of centuries. A thousand pities that the greatest observing astronomer
of antiquity could not, like one of his great precursors, have approached
astronomy from the stand-point of geography and poetry. Had he done
so, perhaps he might have reflected, like Aristarchus before him,
that it seems absurd for our earth to hold the giant sun in thraldom;
then perhaps his imagination would have reached out to the heliocentric
doctrine, and the cobweb hypothesis of epicycles, with that yet more
intangible figment of the perfect circle, might have been wiped away.

But it was not to be. With Aristarchus the scientific imagination
had reached its highest flight; but with Hipparchus it was beginning
to settle back into regions of foggier atmosphere and narrower horizons.
For what, after all, does it matter that Hipparchus should go on to
measure the precise length of the year and the apparent size of the
moon's disk; that he should make a chart of the heavens showing the
place of 1080 stars; even that he should discover the precession of
the equinox;---what, after all, is the significance of these details
as against the all-essential fact that the greatest scientific authority
of his century---the one truly heroic scientific figure of his epoch---should
have lent all the forces of his commanding influence to the old, false
theory of cosmology, when the true theory had been propounded and
when he, perhaps, was the only man in the world who might have substantiated
and vitalized that theory? It is easy to overestimate the influence
of any single man, and, contrariwise, to underestimate the power of
the Zeitgeist. But when we reflect that the doctrines of Hipparchus,
as promulgated by Ptolemy, became, as it were, the last word of astronomical
science for both the Eastern and Western worlds, and so continued
after a thousand years, it is perhaps not too much to say that Hipparchus,
{}``the lover of truth,''\ missed one of the greatest opportunities
for the promulgation of truth ever vouchsafed to a devotee of pure
science.

But all this, of course, detracts nothing from the merits of Hipparchus
as an observing astronomer. A few words more must be said as to his
specific discoveries in this field. According to his measurement,
the tropic year consists of 365 days, 5 hours, and 49 minutes, varying
thus only 12 seconds from the true year, as the modern astronomer
estimates it. Yet more remarkable, because of the greater difficulties
involved, was Hipparchus's attempt to measure the actual distance
of the moon. Aristarchus had made a similar attempt before him. Hipparchus
based his computations on studies of the moon in eclipse, and he reached
the conclusion that the distance of the moon is equal to 59 radii
of the earth (in reality it is 60.27 radii). Here, then, was the measure
of the base-line of that famous triangle with which Aristarchus had
measured the distance of the sun. Hipparchus must have known of that
measurement, since he quotes the work of Aristarchus in other fields.
Had he now but repeated the experiment of Aristarchus, with his perfected
instruments and his perhaps greater observational skill, he was in
position to compute the actual distance of the sun in terms not merely
of the moon's distance but of the earth's radius. And now there was
the experiment of Eratosthenes to give the length of that radius in
precise terms. In other words, Hipparchus might have measured the
distance of the sun in stadia. But if he had made the attempt---and,
indeed, it is more than likely that he did so---the elements of error
in his measurements would still have kept him wide of the true figures.

The chief studies of Hipparchus were directed, as we have seen, towards
the sun and the moon, but a phenomenon that occurred in the year 134
B.C.\ led him for a time to give more particular attention to the
fixed stars. The phenomenon in question was the sudden outburst of
a new star; a phenomenon which has been repeated now and again, but
which is sufficiently rare and sufficiently mysterious to have excited
the unusual attention of astronomers in all generations. Modern science
offers an explanation of the phenomenon, as we shall see in due course.
We do not know that Hipparchus attempted to explain it, but he was
led to make a chart of the heavens, probably with the idea of guiding
future observers in the observation of new stars. Here again Hipparchus
was not altogether an innovator, since a chart showing the brightest
stars had been made by Eratosthenes; but the new charts were much
elaborated.

The studies of Hipparchus led him to observe the stars chiefly with
reference to the meridian rather than with reference to their rising,
as had hitherto been the custom. In making these studies of the relative
position of the stars, Hipparchus was led to compare his observations
with those of the Babylonians, which, it was said, Alexander had caused
to be transmitted to Greece. He made use also of the observations
of Aristarchus and others of his Greek precursors. The result of his
comparisons proved that the sphere of the fixed stars had apparently
shifted its position in reference to the plane of the sun's orbit---that
is to say, the plane of the ecliptic no longer seemed to cut the sphere
of the fixed stars at precisely the point where the two coincided
in former centuries. The plane of the ecliptic must therefore be conceived
as slowly revolving in such a way as gradually to circumnavigate the
heavens. This important phenomenon is described as the precession
of the \textit{\emph{equinoxes}}.

It is much in question whether this phenomenon was not known to the
ancient Egyptian astronomers; but in any event, Hipparchus is to be
credited with demonstrating the fact and making it known to the Western
world. A further service was rendered theoretical astronomy by Hipparchus
through his invention of the planosphere, an instrument for the representation
of the mechanism of the heavens. His computations of the properties
of the spheres led him also to what was virtually a discovery of the
method of trigonometry, giving him, therefore, a high position in
the field of mathematics. All in all, then, Hipparchus is a most heroic
figure. He may well be considered the greatest star-gazer of antiquity,
though he cannot, without injustice to his great precursors, be allowed
the title which is sometimes given him of {}``father of systematic
astronomy.''


\section*{\raggedright CTESIBIUS AND HERO: MAGICIANS OF ALEXANDRIA}

\addcontentsline{toc}{section}{CTESIBIUS AND HERO: MAGICIANS\\
OF ALEXANDRIA}

Just about the time when Hipparchus was working out at Rhodes his
puzzles of celestial mechanics, there was a man in Alexandria who
was exercising a strangely inventive genius over mechanical problems
of another sort; a man who, following the example set by Archimedes
a century before, was studying the problems of matter and putting
his studies to practical application through the invention of weird
devices. The man's name was Ctesibius. We know scarcely more of him
than that he lived in Alexandria, probably in the first half of the
second century B.C. His antecedents, the place and exact time of his
birth and death, are quite unknown. Neither are we quite certain as
to the precise range of his studies or the exact number of his discoveries.
It appears that he had a pupil named Hero, whose personality, unfortunately,
is scarcely less obscure than that of his master, but who wrote a
book through which the record of the master's inventions was preserved
to posterity. Hero, indeed, wrote several books, though only one of
them has been preserved. The ones that are lost bear the following
suggestive titles: \emph{On the Construction of Slings}; \emph{On
the Construction of Missiles}; \emph{On the Automaton}; \emph{On the
Method of Lifting Heavy Bodies}; \emph{On the Dioptric or Spying-tube}.
The work that remains is called \emph{Pneumatics}, and so interesting
a work it is as to make us doubly regret the loss of its companion
volumes. Had these other books been preserved we should doubtless
have a clearer insight than is now possible into some at least of
the mechanical problems that exercised the minds of the ancient philosophers.
The book that remains is chiefly concerned, as its name implies, with
the study of gases, or, rather, with the study of a single gas, this
being, of course, the air. But it tells us also of certain studies
in the dynamics of water that are most interesting, and for the historian
of science most important.

Unfortunately, the pupil of Ctesibius, whatever his ingenuity, was
a man with a deficient sense of the ethics of science. He tells us
in his preface that the object of his book is to record some ingenious
discoveries of others, together with additional discoveries of his
own, but nowhere in the book itself does he give us the slightest
clew as to where the line is drawn between the old and the new. Once,
in discussing the weight of water, he mentions the law of Archimedes
regarding a floating body, but this is the only case in which a scientific
principle is traced to its source or in which credit is given to any
one for a discovery. This is the more to be regretted because Hero
has discussed at some length the theories involved in the treatment
of his subject. This reticence on the part of Hero, combined with
the fact that such somewhat later writers as Pliny and Vitruvius do
not mention Hero's name, while they frequently mention the name of
his master, Ctesibius, has led modern critics to a somewhat sceptical
attitude regarding the position of Hero as an actual discoverer.

The man who would coolly appropriate some discoveries of others under
cloak of a mere prefatorial reference was perhaps an expounder rather
than an innovator, and had, it is shrewdly suspected, not much of
his own to offer. Meanwhile, it is tolerably certain that Ctesibius
was the discoverer of the principle of the siphon, of the forcing-pump,
and of a pneumatic organ. An examination of Hero's book will show
that these are really the chief principles involved in most of the
various interesting mechanisms which he describes. We are constrained,
then, to believe that the inventive genius who was really responsible
for the mechanisms we are about to describe was Ctesibius, the master.
Yet we owe a debt of gratitude to Hero, the pupil, for having given
wider vogue to these discoveries, and in particular for the discussion
of the principles of hydrostatics and pneumatics contained in the
introduction to his book. This discussion furnishes us almost our
only knowledge as to the progress of Greek philosophers in the field
of mechanics since the time of Archimedes.

The main purpose of Hero in his preliminary thesis has to do with
the nature of matter, and recalls, therefore, the studies of Anaxagoras
and Democritus. Hero, however, approaches his subject from a purely
material or practical stand-point. He is an explicit champion of what
we nowadays call the molecular theory of matter. {}``Every body,''\ he
tells us, {}``is composed of minute particles, between which are
empty spaces less than these particles of the body. It is, therefore,
erroneous to say that there is no vacuum except by the application
of force, and that every space is full either of air or water or some
other substance. But in proportion as any one of these particles recedes,
some other follows it and fills the vacant space; therefore there
is no continuous vacuum, except by the application of some force {[}like
suction{]}---that is to say, an absolute vacuum is never found, except
as it is produced artificially.'' Hero brings forward some thoroughly
convincing proofs of the thesis he is maintaining. {}``If there were
no void places between the particles of water,''\ he says, {}``the
rays of light could not penetrate the water; moreover, another liquid,
such as wine, could not spread itself through the water, as it is
observed to do, were the particles of water absolutely continuous.''
The latter illustration is one the validity of which appeals as forcibly
to the physicists of to-day as it did to Hero. The same is true of
the argument drawn from the compressibility of gases. Hero has evidently
made a careful study of this subject. He knows that an inverted tube
full of air may be immersed in water without becoming wet on the inside,
proving that air is a physical substance; but he knows also that this
same air may be caused to expand to a much greater bulk by the application
of heat, or may, on the other hand, be condensed by pressure, in which
case, as he is well aware, the air exerts force in the attempt to
regain its normal bulk. But, he argues, surely we are not to believe
that the particles of air expand to fill all the space when the bulk
of air as a whole expands under the influence of heat; nor can we
conceive that the particles of normal air are in actual contact, else
we should not be able to compress the air. Hence his conclusion, which,
as we have seen, he makes general in its application to all matter,
that there are spaces, or, as he calls them, vacua, between the particles
that go to make up all substances, whether liquid, solid, or gaseous.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S246}\end{center}

\noindent \begin{center}\noun{\small Device for Causing the Doors
of the Temple to Open When the Fire on the Altar is Lighted}\end{center}{\small \par}

\noindent \emph{\footnotesize (Air heated in the altar F drives water
from the closed receptacle H through the tube KL into the bucket M,
which descends through gravity, thus opening the doors. When the altar
cools, the air contracts, the water is sucked from the bucket, and
the weight and pulley close the doors.) }
\end{figure}
Here, clearly enough, was the idea of the {}``atomic''\ nature
of matter accepted as a fundamental notion. The argumentative attitude
assumed by Hero shows that the doctrine could not be expected to go
unchallenged. But, on the other hand, there is nothing in his phrasing
to suggest an intention to claim originality for any phase of the
doctrine. We may infer that in the three hundred years that had elapsed
since the time of Anaxagoras, that philosopher's idea of the molecular
nature of matter had gained fairly wide currency. As to the expansive
power of gas, which Hero describes at some length without giving us
a clew to his authorities, we may assume that Ctesibius was an original
worker, yet the general facts involved were doubtless much older than
his day. Hero, for example, tells us of the cupping-glass used by
physicians, which he says is made into a vacuum by burning up the
air in it; but this apparatus had probably been long in use, and Hero
mentions it not in order to describe the ordinary cupping-glass which
is referred to, but a modification of it. He refers to the old form
as if it were something familiar to all.

Again, we know that Empedocles studied the pressure of the air in
the fifth century B.C., and discovered that it would support a column
of water in a closed tube, so this phase of the subject is not new.
But there is no hint anywhere before this work of Hero of a clear
understanding that the expansive properties of the air when compressed,
or when heated, may be made available as a motor power. Hero, however,
has the clearest notions on the subject and puts them to the practical
test of experiment. Thus he constructs numerous mechanisms in which
the expansive power of air under pressure is made to do work, and
others in which the same end is accomplished through the expansive
power of heated air. For example, the doors of a temple are made to
swing open automatically when a fire is lighted on a distant altar,
closing again when the fire dies out---effects which must have filled
the minds of the pious observers with bewilderment and wonder, serving
a most useful purpose for the priests, who alone, we may assume, were
in the secret. There were two methods by which this apparatus was
worked. In one the heated air pressed on the water in a close retort
connected with the altar, forcing water out of the retort into a bucket,
which by its weight applied a force through pulleys and ropes that
turned the standards on which the temple doors revolved. When the
fire died down the air contracted, the water was siphoned back from
the bucket, which, being thus lightened, let the doors close again
through the action of an ordinary weight. The other method was a slight
modification, in which the retort of water was dispensed with and
a leather sack like a large football substitued. The ropes and pulleys
were connected with this sack, which exerted a pull when the hot air
expanded, and which collapsed and thus relaxed its strain when the
air cooled. A glance at the illustrations taken from Hero's book will
make the details clear.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S248}\end{center}

\noindent \begin{center}\noun{\small The Steam-Engine of Hero}\end{center}{\small \par}

\noindent \emph{\footnotesize (The steam generated in the receptacle
AB passes through the tube EF into the globe, and escapes through
the bent tubes H and K, causing the globe to rotate on the axis LG.) }
\end{figure}
Other mechanisms utilized a somewhat different combination of weights,
pulleys, and siphons, operated by the expansive power of air, unheated
but under pressure, such pressure being applied with a force-pump,
or by the weight of water running into a closed receptacle. One such
mechanism gives us a constant jet of water or perpetual fountain.
Another curious application of the principle furnishes us with an
elaborate toy, consisting of a group of birds which alternately whistle
or are silent, while an owl seated on a neighboring perch turns towards
the birds when their song begins and away from them when it ends.
The {}``singing'' of the birds, it must be explained, is produced
by the expulsion of air through tiny tubes passing up through their
throats from a tank below. The owl is made to turn by a mechanism
similar to that which manipulates the temple doors. The pressure is
supplied merely by a stream of running water, and the periodical silence
of the birds is due to the fact that this pressure is relieved through
the automatic siphoning off of the water when it reaches a certain
height. The action of the siphon, it may be added, is correctly explained
by Hero as due to the greater weight of the water in the longer arm
of the bent tube. As before mentioned, the siphon is repeatedly used
in these mechanisms of Hero. The diagram will make clear the exact
application of it in the present most ingenious mechanism. We may
add that the principle of the whistle was a favorite one of Hero.
By the aid of a similar mechanism he brought about the blowing of
trumpets when the temple doors were opened, a phenomenon which must
greatly have enhanced the mystification. It is possible that this
principle was utilized also in connection with statues to produce
seemingly supernatural effects. This may be the explanation of the
tradition of the speaking statue in the temple of Ammon at Thebes.

The utilization of the properties of compressed air was not confined,
however, exclusively to mere toys, or to produce miraculous effects.
The same principle was applied to a practical fire-engine, worked
by levers and force-pumps; an apparatus, in short, altogether similar
to that still in use in rural districts. A slightly different application
of the motive power of expanding air is furnished in a very curious
toy called {}``the dancing figures.'' In this, air heated in a retort
like a miniature altar is allowed to escape through the sides of two
pairs of revolving arms precisely like those of the ordinary revolving
fountain with which we are accustomed to water our lawns, the revolving
arms being attached to a plane on which several pairs of \textit{\emph{statuettes}}
representing dancers are placed. An even more interesting application
of this principle of setting a wheel in motion is furnished in a mechanism
which must be considered the earliest of steam-engines. Here, as the
name implies, the gas supplying the motive power is actually steam.
The apparatus made to revolve is a globe connected with the steam-retort
by a tube which serves as one of its axes, the steam escaping from
the globe through two bent tubes placed at either end of an equatorial
diameter. It does not appear that Hero had any thought of making practical
use of this steam-engine. It was merely a curious toy---nothing more.
Yet had not the age that succeeded that of Hero been one in which
inventive genius was dormant, some one must soon have hit upon the
idea that this steam-engine might be improved and made to serve a
useful purpose. As the case stands, however, there was no advance
made upon the steam motor of Hero for almost two thousand years. And,
indeed, when the practical application of steam was made, towards
the close of the eighteenth century, it was made probably quite without
reference to the experiment of Hero, though knowledge of his toy may
perhaps have given a clew to Watt or his predecessors.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth,
  height=0.60\paperwidth,
  keepaspectratio]{1hsci10-Wil1S250}\end{center}

\noindent \begin{center}\noun{\small The Slot-Machine of Hero}\end{center}{\small \par}

\noindent \emph{\footnotesize (The coin introduced at A falls on the
lever R, and by its weight opens the valve S, permitting the liquid
to escape through the invisible tube LM. As the lever tips, the coin
slides off and the valve closes. The liquid in tank must of course
be kept above F.) }
\end{figure}
In recent times there has been a tendency to give to this steam-engine
of Hero something more than full meed of appreciation. To be sure,
it marked a most important principle in the conception that steam
might be used as a motive power, but, except in the demonstration
of this principle, the mechanism of Hero was much too primitive to
be of any importance. But there is one mechanism described by Hero
which was a most explicit anticipation of a device, which presumably
soon went out of use, and which was not reinvented until towards the
close of the nineteenth century. This was a device which has become
familiar in recent times as the penny-in-the-slot machine. When towards
the close of the nineteenth century some inventive craftsman hit upon
the idea of an automatic machine to supply candy, a box of cigarettes,
or a whiff of perfumery, he may or may not have borrowed his idea
from the slot-machine of Hero; but in any event, instead of being
an innovator he was really two thousand years behind the times, for
the slot-machine of Hero is the precise prototype of these modern
ones.

The particular function which the mechanism of Hero was destined to
fulfil was the distribution of a jet of water, presumably used for
sacramental purposes, which was given out automatically when a five-drachma
coin was dropped into the slot at the top of the machine. The internal
mechanism of the machine was simple enough, consisting merely of a
lever operating a valve which was opened by the weight of the coin
dropping on the little shelf at the end of the lever, and which closed
again when the coin slid off the shelf. The illustration will show
how simple this mechanism was. Yet to the worshippers, who probably
had entered the temple through doors miraculously opened, and who
now witnessed this seemingly intelligent response of a machine, the
result must have seemed mystifying enough; and, indeed, for us also,
when we consider how relatively crude was the mechanical knowledge
of the time, this must seem nothing less than marvellous. As in imagination
we walk up to the sacred tank, drop our drachma in the slot, and hold
our hand for the spurt of holy-water, can we realize that this is
the land of the Pharaohs, not England or America; that the kingdom
of the Ptolemies is still at its height; that the republic of Rome
is mistress of the world; that all Europe north of the Alps is inhabited
solely by barbarians; that Cleopatra and Julius C\ae{}sar are yet
unborn; that the Christian era has not yet begun? Truly, it seems
as if there could be no new thing under the sun.


\chapter*{\raggedright X.\ SCIENCE OF THE ROMAN PERIOD}

\addcontentsline{toc}{chapter}{X. SCIENCE OF THE ROMAN PERIOD}

\markboth{A HISTORY OF SCIENCE, BOOK I}{X. SCIENCE OF THE ROMAN PERIOD}

We have seen that the third century B.C.\ was a time when Alexandrian
science was at its height, but that the second century produced also
in Hipparchus at least one investigator of the very first rank; though,
to be sure, Hipparchus can be called an Alexandrian only by courtesy.
In the ensuing generations the Greek capital at the mouth of the Nile
continued to hold its place as the centre of scientific and philosophical
thought. The kingdom of the Ptolemies still flourished with at least
the outward appearances of its old-time glory, and a company of grammarians
and commentators of no small merit could always be found in the service
of the famous museum and library; but the whole aspect of world-history
was rapidly changing. Greece, after her brief day of political supremacy,
was sinking rapidly into desuetude, and the hard-headed Roman in the
West was making himself master everywhere. While Hipparchus of Rhodes
was in his prime, Corinth, the last stronghold of the main-land of
Greece, had fallen before the prowess of the Roman, and the kingdom
of the Ptolemies, though still nominally free, had begun to come within
the sphere of Roman influence.

Just what share these political changes had in changing the aspect
of Greek thought is a question regarding which difference of opinion
might easily prevail; but there can be no question that, for one reason
or another, the Alexandrian school as a creative centre went into
a rapid decline at about the time of the Roman rise to world-power.
There are some distinguished names, but, as a general rule, the spirit
of the times is reminiscent rather than creative; the workers tend
to collate the researches of their predecessors rather than to make
new and original researches for themselves. Eratosthenes, the inventive
world-measurer, was succeeded by Strabo, the industrious collator
of facts; Aristarchus and Hipparchus, the originators of new astronomical
methods, were succeeded by Ptolemy, the perfecter of their methods
and the systematizer of their knowledge. Meanwhile, in the West, Rome
never became a true culture-centre. The great genius of the Roman
was political; the Augustan Age produced a few great historians and
poets, but not a single great philosopher or creative devotee of science.
Cicero, Lucian, Seneca, Marcus Aurelius, give us at best a reflection
of Greek philosophy. Pliny, the one world-famous name in the scientific
annals of Rome, can lay claim to no higher credit than that of a marvellously
industrious collector of facts---the compiler of an encyclop\ae{}dia
which contains not one creative touch.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S254}\end{center}

\noindent \begin{center}\noun{\small Pliny}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (From an old print.)}\end{center}
\end{figure}
All in all, then, this epoch of Roman domination is one that need
detain the historian of science but a brief moment. With the culmination
of Greek effort in the so-called Hellenistic period we have seen ancient
science at its climax. The Roman period is but a time of transition,
marking, as it were, a plateau on the slope between those earlier
heights and the deep, dark valleys of the Middle Ages. Yet we cannot
quite disregard the efforts of such workers as those we have just
named. Let us take a more specific glance at their accomplishments.


\section*{\raggedright STRABO THE GEOGRAPHER}

\addcontentsline{toc}{section}{STRABO THE GEOGRAPHER}

The earliest of these workers in point of time is Strabo. This most
famous of ancient geographers was born in \textit{\emph{Amasia}},
Pontus, about 63 B.C., and lived to the year 24 A.D., living, therefore,
in the age of C\ae{}sar and Augustus, during which the final transformation
in the political position of the kingdom of Egypt was effected. The
name of Strabo in a modified form has become popularized through a
curious circumstance. The geographer, it appears, was afflicted with
a peculiar squint of the eyes, hence the name strabismus, which the
modern oculist applies to that particular infirmity.

Fortunately, the great geographer has not been forced to depend upon
hearsay evidence for recognition. His comprehensive work on geography
has been preserved in its entirety, being one of the few expansive
classical writings of which this is true. The other writings of Strabo,
however, including certain histories of which reports have come down
to us, are entirely lost. The geography is in many ways a remarkable
book. It is not, however, a work in which any important new principles
are involved. Rather is it typical of its age in that it is an elaborate
compilation and a critical review of the labors of Strabo's predecessors.
Doubtless it contains a vast deal of new information as to the details
of geography---precise areas and distance, questions of geographical
locations as to latitude and zones, and the like. But however important
these details may have been from a contemporary stand-point, they,
of course, can have nothing more than historical interest to posterity.
The value of the work from our present stand-point is chiefly due
to the criticisms which Strabo passes upon his forerunners, and to
the incidental historical and scientific references with which his
work abounds. Being written in this closing period of ancient progress,
and summarizing, as it does, in full detail the geographical knowledge
of the time, it serves as an important guide-mark for the student
of the progress of scientific thought. We cannot do better than briefly
to follow Strabo in his estimates and criticisms of the work of his
predecessors, taking note thus of the point of view from which he
himself looked out upon the world. We shall thus gain a clear idea
as to the state of scientific geography towards the close of the classical
epoch.

\begin{quote}
{}``If the scientific investigation of any subject be the proper
avocation of the philosopher,''\ says Strabo, {}``geography, the
science of which we propose to treat, is certainly entitled to a high
place; and this is evident from many considerations. They who first
undertook to handle the matter were distinguished men. Homer, Anaximander
the Milesian, and Hec\ae{}us (his fellow-citizen according to Eratosthenes),
Democritus, Eudoxus, Dic\ae{}archus, and \textit{\emph{Ephorus}},
with many others, and after these, Eratosthenes, Polybius, and Posidonius,
all of them philosophers. Nor is the great learning through which
alone this subject can be approached possessed by any but a person
acquainted with both human and divine things, and these attainments
constitute what is called philosophy. In addition to its vast importance
in regard to social life and the art of government, geography unfolds
to us a celestial phenomena, acquaints us with the occupants of the
land and ocean, and the vegetation, fruits, and peculiarities of the
various quarters of the earth, a knowledge of which marks him who
cultivates it as a man earnest in the great problem of life and happiness.''
\end{quote}
{}

Strabo goes on to say that in common with other critics, including
Hipparchus, he regards Homer as the first great geographer. He has
much to say on the geographical knowledge of the bard, but this need
not detain us. We are chiefly concerned with his comment upon his
more recent predecessors, beginning with Eratosthenes. The constant
reference to this worker shows the important position which he held.
Strabo appears neither as detractor nor as partisan, but as one who
earnestly desires the truth. Sometimes he seems captious in his criticisms
regarding some detail, nor is he always correct in his emendations
of the labors of others; but, on the whole, his work is marked by
an evident attempt at fairness. In reading his book, however, one
is forced to the conclusion that Strabo is an investigator of details,
not an original thinker. He seems more concerned with precise measurements
than with questionings as to the open problems of his science. Whatever
he accepts, then, may be taken as virtually the stock doctrine of
the period.

\begin{quote}
{}``As the size of the earth,''\ he says, {}``has been demonstrated
by other writers, we shall here take for granted and receive as accurate
what they have advanced. We shall also assume that the earth is spheroidal,
that its surface is likewise spheroidal and, above all, that bodies
have a tendency towards its centre, which latter point is clear to
the perception of the most average understanding. However, we may
show summarily that the earth is spheroidal, from the consideration
that all things, however distant, tend to its centre, and that every
body is attracted towards its centre by gravity. This is more distinctly
proved from observations of the sea and sky, for here the evidence
of the senses and common observation is alone requisite. The convexity
of the sea is a further proof of this to those who have sailed, for
they cannot perceive lights at a distance when placed at the same
level as their eyes, and if raised on high they at once become perceptible
to vision though at the same time farther removed. So when the eye
is raised it sees what before was utterly imperceptible. Homer speaks
of this when he says:\ 
\begin{quote}
{}```Lifted up on the vast wave he quickly beheld afar.'
\end{quote}
{}``Sailors as they approach their destination behold the shore continually
raising itself to their view, and objects which had at first seemed
low begin to lift themselves. Our \textit{\emph{gnomons}}, also, are,
among other things, evidence of the revolution of the heavenly bodies,
and common-sense at once shows us that if the depth of the earth were
infinite such a revolution could not take place.''%
\footnote{\emph{The Geography of Strabo}, translated by H.\ C.\ Hamilton and
W.\ Falconer, 3 \textit{\emph{vols}}., London, 1857, Vol.\ I, \textit{\emph{pp}}.\ 19,
20.%
}
\end{quote}
{}

Elsewhere Strabo criticises Eratosthenes for having entered into a
long discussion as to the form of the earth. This matter, Strabo thinks,
{}``should have been disposed of in the compass of a few words.''
Obviously this doctrine of the globe's sphericity had, in the course
of 600 years, become so firmly established among the Greek thinkers
as to seem almost axiomatic. We shall see later on how the Western
world made a curious recession from this seemingly secure position
under stimulus of an Oriental misconception. As to the size of the
globe, Strabo is disposed to accept without particular comment the
measurements of Eratosthenes. He speaks, however, of {}``more recent
measurements,'' referring in particular to that adopted by Posidonius,
according to which the circumference is only about one hundred and
eighty thousand stadia. Posidonius, we may note in passing, was a
contemporary and friend of Cicero, and hence lived shortly before
the time of Strabo. His measurement of the earth was based on observations
of a star which barely rose above the southern horizon at Rhodes as
compared with the height of the same star when observed at Alexandria.
This measurement of Posidonius, together with the even more famous
measurement of Eratosthenes, appears to have been practically the
sole guide as to the size of the earth throughout the later periods
of antiquity, and, indeed, until the later Middle Ages.

As becomes a writer who is primarily geographer and historian rather
than astronomer, Strabo shows a much keener interest in the habitable
portions of the globe than in the globe as a whole. He assures us
that this habitable portion of the earth is a great island, {}``since
wherever men have approached the termination of the land, the sea,
which we designate ocean, has been met with, and reason assures us
of the similarity of this place which our senses have not been tempted
to survey.'' He points out that whereas sailors have not circumnavigated
the globe, that they had not been prevented from doing so by any continent,
and it seems to him altogether unlikely that the Atlantic Ocean is
divided into two seas by narrow isthmuses so placed as to prevent
circumnavigation. {}``How much more probable that it is confluent
and uninterrupted. This theory,''\ he adds, {}``goes better with
the ebb and flow of the ocean. Moreover {[}and here his reasoning
becomes more fanciful{]}, the greater the amount of moisture surrounding
the earth, the easier would the heavenly bodies be supplied with vapor
from thence.'' Yet he is disposed to believe, following Plato, that
the tradition {}``concerning the island of Atlantos might be received
as something more than idle fiction, it having been related by Solon,
on the authority of the Egyptian priests, that this island, almost
as large as a continent, was formerly in existence although now it
had disappeared.''%
\footnote{\emph{Ibid}., p.\ 154.%
}

In a word, then, Strabo entertains no doubt whatever that it would
be possible to sail around the globe from Spain to India. Indeed,
so matter-of-fact an inference was this that the feat of Columbus
would have seemed less surprising in the first century of our era
than it did when actually performed in the fifteenth century. The
terrors of the great ocean held the mariner back, rather than any
doubt as to where he would arrive at the end of the voyage.

Coupled with the idea that the habitable portion of the earth is an
island, there was linked a tolerably definite notion as to the shape
of this island. This shape Strabo likens to a military cloak. The
comparison does not seem peculiarly apt when we are told presently
that the length of the habitable earth is more than twice its breadth.
This idea, Strabo assures us, accords with the most accurate observations
{}``both ancient and modern.'' These observations seemed to show
that it is not possible to live in the region close to the equator,
and that, on the other hand, the cold temperature sharply limits the
habitability of the globe towards the north. All the civilization
of antiquity clustered about the Mediterranean, or extended off towards
the east at about the same latitude. Hence geographers came to think
of the habitable globe as having the somewhat lenticular shape which
a crude map of these regions suggests. We have already had occasion
to see that at an earlier day Anaxagoras was perhaps influenced in
his conception of the shape of the earth by this idea, and the constant
references of Strabo impress upon us the thought that this long, relatively
narrow area of the earth's surface is the only one which can be conceived
of as habitable.

Strabo had much to tell us concerning zones, which, following Posidonius,
he believes to have been first described by Parmenides. We may note,
however, that other traditions assert that both Thales and Pythagoras
had divided the earth into zones. The number of zones accepted by
Strabo is five, and he criticises Polybius for making the number six.
The five zones accepted by Strabo are as follows: the uninhabitable
torrid zone lying in the region of the equator; a zone on either side
of this extending to the tropic; and then the temperate zones extending
in either direction from the tropic to the arctic regions. There seems
to have been a good deal of dispute among the scholars of the time
as to the exact arrangement of these zones, but the general idea that
the north-temperate zone is the part of the earth with which the geographer
deals seemed clearly established. That the south-temperate zone would
also present a habitable area is an idea that is sometimes suggested,
though seldom or never distinctly expressed. It is probable that different
opinions were held as to this, and no direct evidence being available,
a cautiously scientific geographer like Strabo would naturally avoid
the expression of an opinion regarding it. Indeed, his own words leave
us somewhat in doubt as to the precise character of his notion regarding
the zones. Perhaps we shall do best to quote them:\ 

{}``Let the earth be supposed to consist of five zones.\ (1)\ The
equatorial circle described around it.\ (2)\ Another parallel to
this, and defining the frigid zone of the northern hemisphere. (3)\ A
circle passing through the poles and cutting the two preceding circles
at right-\ angles. The northern hemisphere contains two quarters
of the earth, which are bounded by the equator and circle passing
through the poles. Each of these quarters should be supposed to contain
a four-sided district, its northern side being of one-half of the
parallel next the pole, its southern by the half of the equator, and
its remaining sides by two segments of the circle drawn through the
poles, opposite to each other, and equal in length. In one of these
(which of them is of no consequence)\ the earth which we inhabit
is situated, surrounded by a sea and similar to an island. This, as
we said before, is evident both to our senses and to our reason. But
let any one doubt this, it makes no difference so far as geography
is concerned whether you believe the portion of the earth which we
inhabit to be an island or only admit what we know from experience---namely,
that whether you start from the east or the west you may sail all
around it. Certain intermediate spaces may have been left (unexplored),
but these are as likely to be occupied by sea as uninhabited land.
The object of the geographer is to describe known countries. Those
which are unknown he passes over equally with those beyond the limits
of the inhabited earth. It will, therefore, be sufficient for describing
the contour of the island we have been speaking of, if we join by
a right line the outmost points which, up to this time, have been
explored by voyagers along the coast on either side.''%
\footnote{\emph{Ibid}., \textit{\emph{pp}}.\ 169, 170.%
}

We may pass over the specific criticisms of Strabo upon various explorations
that seem to have been of great interest to his contemporaries, including
an alleged trip of one Eudoxus out into the Atlantic, and the journeyings
of Pytheas in the far north. It is Pytheas, we may add, who was cited
by Hipparchus as having made the mistaken observation that the length
of the shadow of the gnomon is the same at Marseilles and Byzantium,
hence that these two places are on the same parallel. Modern commentators
have defended Pytheas as regards this observation, claiming that it
was Hipparchus and not Pytheas who made the second observation from
which the faulty induction was drawn. The point is of no great significance,
however, except as showing that a correct method of determining the
problems of latitude had thus early been suggested. That faulty observations
and faulty application of the correct principle should have been made
is not surprising. Neither need we concern ourselves with the details
as to the geographical distances, which Strabo found so worthy of
criticism and controversy. But in leaving the great geographer we
may emphasize his point of view and that of his contemporaries by
quoting three fundamental principles which he reiterates as being
among the {}``facts established by natural philosophers.'' He tells
us that {}``(1)\ The earth and heavens are spheroidal.\ (2)\ The
tendency of all bodies having weight is towards a centre.\ (3) Further,
the earth being spheroidal and having the same centre as the heavens,
is motionless, as well as the axis that passes through both it and
the heavens. The heavens turn round both the earth and its axis, from
east to west. The fixed stars turn round with it at the same rate
as the whole. These fixed stars follow in their course parallel circles,
the principal of which are the equator, two tropics, and the arctic
circles; while the planets, the sun, and the moon describe certain
circles comprehended within the zodiac.''%
\footnote{\emph{Ibid}., \textit{\emph{pp}}.\ 166, 167.%
}

Here, then, is a curious mingling of truth and error. The Pythagorean
doctrine that the earth is round had become a commonplace, but it
would appear that the theory of Aristarchus, according to which the
earth is in motion, has been almost absolutely forgotten. Strabo does
not so much as refer to it; neither, as we shall see, is it treated
with greater respect by the other writers of the period.


\section*{\raggedright TWO FAMOUS EXPOSITORS---PLINY AND PTOLEMY}

\addcontentsline{toc}{section}{TWO FAMOUS EXPOSITORS---\\
PLINY AND PTOLEMY}

While Strabo was pursuing his geographical studies at Alexandria,
a young man came to Rome who was destined to make his name more widely
known in scientific annals than that of any other Latin writer of
antiquity. This man was \textit{\emph{Plinius}} \emph{}\textit{\emph{Secundus}},
who, to distinguish him from his nephew, a famous writer in another
field, is usually spoken of as Pliny the Elder. There is a famous
story to the effect that the great Roman historian Livy on one occasion
addressed a casual associate in the amphitheatre at Rome, and on learning
that the stranger hailed from the outlying Spanish province of the
empire, remarked to him, {}``Yet you have doubtless heard of my writings
even there.'' {}``Then,''\ replied the stranger, {}``you must
be either Livy or Pliny.''

The anecdote illustrates the wide fame which the Roman naturalist
achieved in his own day. And the records of the Middle Ages show that
this popularity did not abate in succeeding times. Indeed, the \emph{Natural
History} of Pliny is one of the comparatively few bulky writings of
antiquity that the efforts of copyists have preserved to us almost
entire. It is, indeed, a remarkable work and eminently typical of
its time; but its author was an industrious compiler, not a creative
genius. As a monument of industry it has seldom been equalled, and
in this regard it seems the more remarkable inasmuch as Pliny was
a practical man of affairs who occupied most of his life as a soldier
fighting the battles of the empire. He compiled his book in the leisure
hours stolen from sleep, often writing by the light of the camp-fire.
Yet he cites or quotes from about four thousand works, most of which
are known to us only by his references. Doubtless Pliny added much
through his own observations. We know how keen was his desire to investigate,
since he lost his life through attempting to approach the crater of
Vesuvius on the occasion of that memorable eruption which buried the
cities of Herculaneum and Pompeii.

Doubtless the wandering life of the soldier had given Pliny abundant
opportunity for personal observation in his favorite fields of botany
and zoology. But the records of his own observations are so intermingled
with knowledge drawn from books that it is difficult to distinguish
the one from the other. Nor does this greatly matter, for whether
as closet-student or field-naturalist, Pliny's trait of mind is essentially
that of the compiler. He was no philosophical thinker, no generalizer,
no path-maker in science. He lived at the close of a great progressive
epoch of thought; in one of those static periods when numberless observers
piled up an immense mass of details which might advantageously be
sorted into a kind of encyclop\ae{}dia. Such an encyclop\ae{}dia
is the so-called \emph{Natural History} of Pliny. It is a vast jumble
of more or less uncritical statements regarding almost every field
of contemporary knowledge. The descriptions of animals and plants
predominate, but the work as a whole would have been immensely improved
had the compiler shown a more critical spirit. As it is, he seems
rather disposed to quote any interesting citation that he comes across
in his omnivorous readings, shielding himself behind an equivocal
{}``it is said,''\ or {}``so and so alleges.'' A single illustration
will suffice to show what manner of thing is thought worthy of repetition.

\begin{quote}
{}``It is asserted,''\ he says, {}``that if the fish called a
sea-star is smeared with the fox's blood and then nailed to the upper
lintel of the door, or to the door itself, with a copper nail, no
noxious spell will be able to obtain admittance, or, at all events,
be productive of any ill effects.''
\end{quote}
{}

It is easily comprehensible that a work fortified with such practical
details as this should have gained wide popularity. Doubtless the
natural histories of our own day would find readier sale were they
to pander to various superstitions not altogether different from that
here suggested. The man, for example, who believes that to have a
black cat cross his path is a lucky omen would naturally find himself
attracted by a book which took account of this and similar important
details of natural history. Perhaps, therefore, it was its inclusion
of absurdities, quite as much as its legitimate value, that gave vogue
to the celebrated work of Pliny. But be that as it may, the most famous
scientist of Rome must be remembered as a popular writer rather than
as an experimental worker. In the history of the promulgation of scientific
knowledge his work is important; in the history of scientific principles
it may virtually be disregarded.


\section*{\raggedright PTOLEMY, THE LAST GREAT ASTRONOMER OF ANTIQUITY}

\addcontentsline{toc}{section}{PTOLEMY, THE LAST GREAT\\
ASTRONOMER OF ANTIQUITY}

Almost the same thing may be said of Ptolemy, an even more celebrated
writer, who was born not very long after the death of Pliny. The exact
dates of Ptolemy's life are not known, but his recorded observations
extend to the year 151 A.D. He was a working astronomer, and he made
at least one original discovery of some significance---namely, the
observation of a hitherto unrecorded irregularity of the moon's motion,
which came to be spoken of as the moon's evection. This consists of
periodical aberrations from the moon's regular motion in its orbit,
which, as we now know, are due to the gravitation pull of the sun,
but which remained unexplained until the time of Newton. Ptolemy also
made original observations as to the motions of the planets. He is,
therefore, entitled to a respectable place as an observing astronomer;
but his chief fame rests on his writings.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S268}\end{center}

\noindent \begin{center}\noun{\small Ptolemy}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (From an old print.)}\end{center}
\end{figure}
His great works have to do with geography and astronomy. In the former
field he makes an advance upon Strabo, citing the latitude of no fewer
than five thousand places. In the field of astronomy, his great service
was to have made known to the world the labors of Hipparchus. Ptolemy
has been accused of taking the star-chart of his great predecessor
without due credit, and indeed it seems difficult to clear him of
this charge. Yet it is at least open to doubt whether be intended
any impropriety, inasmuch as be all along is sedulous in his references
to his predecessor. Indeed, his work might almost be called an exposition
of the astronomical doctrines of Hipparchus. No one pretends that
Ptolemy is to be compared with the Rhodesian observer as an original
investigator, but as a popular expounder his superiority is evidenced
in the fact that the writings of Ptolemy became practically the sole
astronomical text-book of the Middle Ages both in the East and in
the West, while the writings of Hipparchus were allowed to perish.

The most noted of all the writings of Ptolemy is the work which became
famous under the Arabic name of \emph{Almagest}. This word is curiously
derived from the Greek title \emph{c $\mu $$\varepsilon $$\gamma $$\iota $$\varsigma $$\theta $
$\sigma $$\upsilon $$\nu $$\tau $$\alpha $$\zeta $$\iota $$\sigma $},
{}``the greatest construction,''\ a name given the book to distinguish
it from a work on astrology in four books by the same author. For
convenience of reference it came to be spoken of merely as \emph{c
$\mu $$\varepsilon $$\gamma $$\iota $$\varsigma $$\theta $},
from which the Arabs form the title \emph{Tabair} \textit{al} \emph{Magisthi},
under which title the book was published in the year 827. From this
it derived the word Almagest, by which Ptolemy's work continued to
be known among the Arabs, and subsequently among Europeans when the
book again became known in the West. Ptolemy's book, as has been said,
is virtually an elaboration of the doctrines of Hipparchus. It assumes
that the earth is the fixed centre of the solar system, and that the
stars and planets revolve about it in twenty-four hours, the earth
being, of course, spherical. It was not to be expected that Ptolemy
should have adopted the heliocentric idea of Aristarchus. Yet it is
much to be regretted that he failed to do so, since the deference
which was accorded his authority throughout the Middle Ages would
doubtless have been extended in some measure at least to this theory
as well, had he championed it. Contrariwise, his unqualified acceptance
of the geocentric doctrine sufficed to place that doctrine beyond
the range of challenge.

The \emph{Almagest} treats of all manner of astronomical problems,
but the feature of it which gained it widest celebrity was perhaps
that which has to do with eccentrics and epicycles. This theory was,
of course, but an elaboration of the ideas of Hipparchus; but, owing
to the celebrity of the expositor, it has come to be spoken of as
the theory of Ptolemy. We have sufficiently detailed the theory in
speaking of Hipparchus. It should be explained, however, that, with
both Hipparchus and Ptolemy, the theory of epicycles would appear
to have been held rather as a working hypothesis than as a certainty,
so far as the actuality of the minor spheres or epicycles is concerned.
That is to say, these astronomers probably did not conceive either
the epicycles or the greater spheres as constituting actual solid
substances. Subsequent generations, however, put this interpretation
upon the theory, conceiving the various spheres as actual crystalline
bodies. It is difficult to imagine just how the various epicycles
were supposed to revolve without interfering with the major spheres,
but perhaps this is no greater difficulty than is presented by the
alleged properties of the ether, which physicists of to-day accept
as at least a working hypothesis. We shall see later on how firmly
the conception of concentric crystalline spheres was held to, and
that no real challenge was ever given that theory until the discovery
was made that comets have an orbit that must necessarily intersect
the spheres of the various planets.

Ptolemy's system of geography in eight books, founded on that of \textit{\emph{Marinus}}
of Tyre, was scarcely less celebrated throughout the Middle Ages than
the \emph{Almagest}. It contained little, however, that need concern
us here, being rather an elaboration of the doctrines to which we
have already sufficiently referred. None of Ptolemy's original manuscripts
has come down to us, but there is an alleged fifth-century manuscript
attributed to Agathadamon of Alexandria which has peculiar interest
because it contains a series of twenty-seven elaborately colored maps
that are supposed to be derived from maps drawn up by Ptolemy himself.
In these maps the sea is colored green, the mountains red or dark
yellow, and the land white. Ptolemy assumed that a degree at the equator
was 500 stadia instead of 604 stadia in length. We are not informed
as to the grounds on which this assumption was made, but it has been
suggested that the error was at least partially instrumental in leading
to one very curious result. {}``Taking the parallel of Rhodes,''\ says
Donaldson,%
\footnote{K.\ O.\ Miller and John W.\ Donaldson, \emph{The History of the
Literature of Greece}, 3 \textit{\emph{vols}}., London, Vol. III.,
p.\ 268.%
} {}``he calculated the longitudes from the Fortunate Islands to Cattigara
or the west coast of Borneo at 180$^\circ$, conceiving this to be
one-half the circumference of the globe. The real distance is only
125$^\circ$ or 127$^\circ$, so that his measurement is wrong by
one third of the whole, one-sixth for the error in the measurement
of a degree and one-sixth for the errors in measuring the distance
geometrically. These errors, owing to the authority attributed to
the geography of Ptolemy in the Middle Ages, produced a consequence
of the greatest importance. They really led to the discovery of America.
For the design of Columbus to sail from the west of Europe to the
east of Asia was founded on the supposition that the distance was
less by one third than it really was.'' This view is perhaps a trifle
fanciful, since there is nothing to suggest that the courage of Columbus
would have balked at the greater distance, and since the protests
of the sailors, which nearly thwarted his efforts, were made long
before the distance as estimated by Ptolemy had been covered; nevertheless
it is interesting to recall that the great geographical doctrines,
upon which Columbus must chiefly have based his arguments, had been
before the world in an authoritative form practically unheeded for
more than twelve hundred years, awaiting a champion with courage enough
to put them to the test.


\section*{\raggedright GALEN---THE LAST GREAT ALEXANDRIAN}

\addcontentsline{toc}{section}{GALEN---THE LAST GREAT\\
ALEXANDRIAN}

There is one other field of scientific investigation to which we must
give brief attention before leaving the antique world. This is the
field of physiology and medicine. In considering it we shall have
to do with the very last great scientist of the Alexandrian school.
This was Claudius Galenus, commonly known as Galen, a man whose fame
was destined to eclipse that of all other physicians of antiquity
except Hippocrates, and whose doctrines were to have the same force
in their field throughout the Middle Ages that the doctrines of Aristotle
had for physical science. But before we take up Galen's specific labors,
it will be well to inquire briefly as to the state of medical art
and science in the Roman world at the time when the last great physician
of antiquity came upon the scene.

The Romans, it would appear, had done little in the way of scientific
discoveries in the field of medicine, but, nevertheless, with their
practicality of mind, they had turned to better account many more
of the scientific discoveries of the Greeks than did the discoverers
themselves. The practising physicians in early Rome were mostly men
of Greek origin, who came to the capital after the overthrow of the
Greeks by the Romans. Many of them were slaves, as earning money by
either bodily or mental labor was considered beneath the dignity of
a Roman citizen. The wealthy Romans, who owned large estates and numerous
slaves, were in the habit of purchasing some of these slave doctors,
and thus saving medical fees by having them attend to the health of
their families.

By the beginning of the Christian era medicine as a profession had
sadly degenerated, and in place of a class of physicians who practised
medicine along rational or legitimate lines, in the footsteps of the
great Hippocrates, there appeared great numbers of {}``specialists,''\ most
of them charlatans, who pretended to possess supernatural insight
in the methods of treating certain forms of disease. These physicians
rightly earned the contempt of the better class of Romans, and were
made the object of many attacks by the satirists of the time. Such
specialists travelled about from place to place in much the same manner
as the itinerant {}``Indian doctors''\ and {}``lightning tooth-extractors''\ do
to-day. Eye-doctors seem to have been particularly numerous, and these
were divided into two classes, eye-surgeons and eye-doctors proper.
The eye-surgeon performed such operations as cauterizing for ingrowing
eyelashes and operating upon growths about the eyes; while the eye-doctors
depended entirely upon salves and lotions. These eye-salves were frequently
stamped with the seal of the physician who compounded them, something
like two hundred of these seals being still in existence. There were
besides these quacks, however, reputable eye-doctors who must have
possessed considerable skill in the treatment of certain ophthalmias.
Among some Roman surgical instruments discovered at Rheims were found
also some drugs employed by ophthalmic surgeons, and an analysis of
these show that they contained, among other ingredients, some that
are still employed in the treatment of certain affections of the eye.

One of the first steps taken in recognition of the services of physicians
was by Julius C\ae{}sar, who granted citizenship to all physicians
practising in Rome. This was about fifty years before the Christian
era, and from that time on there was a gradual improvement in the
attitude of the Romans towards the members of the medical profession.
As the Romans degenerated from a race of sturdy warriors and became
more and more depraved physically, the necessity for physicians made
itself more evident. Court physicians, and physicians-in-ordinary,
were created by the emperors, as were also city and district physicians.
In the year 133 A.D. Hadrian granted immunity from taxes and military
service to physicians in recognition of their public services.

The city and district physicians, known as the \textit{archiatri}
\emph{populaires}, treated and cared for the poor without remuneration,
having a position and salary fixed by law and paid them semi-annually.
These were honorable positions, and the \textit{archiatri} were obliged
to give instruction in medicine, without pay, to the poor students.
They were allowed to receive fees and donations from their patients,
but not, however, until the danger from the malady was past. Special
laws were enacted to protect them, and any person subjecting them
to an insult was liable to a fine {}``not exceeding one thousand
pounds.''

An example of Roman practicality is shown in the method of treating
hemorrhage, as described by \textit{\emph{Aulus}} Cornelius \textit{\emph{Celsus}}
(53 B.C.\ to 7 A.D.). Hippocrates and Hippocratic writers treated
hemorrhage by application of cold, pressure, styptics, and sometimes
by actual cauterizing; but they knew nothing of the simple method
of stopping a hemorrhage by a ligature tied around the bleeding vessel.
\textit{\emph{Celsus}} not only recommended tying the end of the injured
vessel, but describes the method of applying two ligatures before
the artery is divided by the surgeon---a common practice among surgeons
at the present time. The cut is made between these two, and thus hemorrhage
is avoided from either end of the divided vessel.

Another Roman surgeon, Heliodorus, not only describes the use of the
ligature in stopping hemorrhage, but also the practice of torsion---twisting
smaller vessels, which causes their lining membrane to contract in
a manner that produces coagulation and stops hemorrhage. It is remarkable
that so simple and practical a method as the use of the ligature in
stopping hemorrhage could have gone out of use, once it had been discovered;
but during the Middle Ages it was almost entirely lost sight of, and
was not reintroduced until the time of Ambroise Pare, in the sixteenth
century.

Even at a very early period the Romans recognized the advantage of
surgical methods on the field of battle. Each soldier was supplied
with bandages, and was probably instructed in applying them, something
in the same manner as is done now in all modern armies. The Romans
also made use of military hospitals and had established a rude but
very practical field-ambulance service. {}``In every troop or bandon
of two or four hundred men, eight or ten stout fellows were deputed
to ride immediately behind the fighting-line to pick up and rescue
the wounded, for which purpose their saddles had two stirrups on the
left side, while they themselves were provided with water-flasks,
and perhaps applied temporary bandages. They were encouraged by a
reward of a piece of gold for each man they rescued. `Noscomi'\ were
male nurses attached to the military hospitals, but not inscribed
`on strength'\ of the legions, and were probably for the most part
of the servile class.''%
\footnote{E.\ T.\ Withington, \emph{Medical History from the Earliest Times},
London, 1894, p.\ 118.%
}

From the time of the early Alexandrians, Herophilus and Erasistratus,
whose work we have already examined, there had been various anatomists
of some importance in the Alexandrian school, though none quite equal
to these earlier workers. The best-known names are those of \textit{\emph{Celsus}}
(of whom we have already spoken), who continued the work of anatomical
investigation, and \textit{\emph{Marinus}}, who lived during the reign
of Nero, and Rufus of Ephesus. Probably all of these would have been
better remembered by succeeding generations had their efforts not
been eclipsed by those of Galen. This greatest of ancient anatomists
was born at Pergamus of Greek parents. His father, Nicon, was an architect
and a man of considerable ability. Until his fifteenth year the youthful
Galen was instructed at home, chiefly by his father; but after that
time he was placed under suitable teachers for instruction in the
philosophical systems in vogue at that period. Shortly after this,
however, the superstitious Nicon, following the interpretations of
a dream, decided that his son should take up the study of medicine,
and placed him under the instruction of several learned physicians.

Galen was a tireless worker, making long tours into Asia Minor and
Palestine to improve himself in pharmacology, and studying anatomy
for some time at Alexandria. He appears to have been full of the superstitions
of the age, however, and early in his career made an extended tour
into western Asia in search of the chimerical {}``jet-stone''---a
stone possessing the peculiar qualities of {}``burning with a bituminous
odor and supposed to possess great potency in curing such diseases
as epilepsy, hysteria, and gout.''

By the time he had reached his twenty-eighth year he had perfected
his education in medicine and returned to his home in Pergamus. Even
at that time he had acquired considerable fame as a surgeon, and his
fellow-citizens showed their confidence in his ability by choosing
him as surgeon to the wounded gladiators shortly after his return
to his native city. In these duties his knowledge of anatomy aided
him greatly, and he is said to have healed certain kinds of wounds
that had previously baffled the surgeons.

In the time of Galen \textit{\emph{dissections}} of the human body
were forbidden by law, and he was obliged to confine himself to \textit{\emph{dissections}}
of the lower animals. He had the advantage, however, of the anatomical
works of Herophilus and Erasistratus, and he must have depended upon
them in perfecting his comparison between the anatomy of men and the
lower animals. It is possible that he did make human \textit{\emph{dissections}}
surreptitiously, but of this we have no proof.

He was familiar with the complicated structure of the bones of the
cranium. He described the vertebr\ae{} clearly, divided them into
groups, and named them after the manner of anatomists of to-day. He
was less accurate in his description of the muscles, although a large
number of these were described by him. Like all anatomists before
the time of Harvey, he had a very erroneous conception of the circulation,
although he understood that the heart was an organ for the propulsion
of blood, and he showed that the arteries of the living animals did
not contain air alone, as was taught by many anatomists. He knew,
also, that the heart was made up of layers of fibres that ran in certain
fixed directions---that is, longitudinal, transverse, and oblique;
but he did not recognize the heart as a muscular organ. In proof of
this he pointed out that all muscles require rest, and as the heart
did not rest it could not be composed of muscular tissue.

Many of his physiological experiments were conducted upon scientific
principles. Thus he proved that certain muscles were under the control
of definite sets of nerves by cutting these nerves in living animals,
and observing that the muscles supplied by them were rendered useless.
He pointed out also that nerves have no power in themselves, but merely
conduct impulses to and from the brain and spinal-cord. He turned
this peculiar knowledge to account in the case of a celebrated sophist,
Pausanias, who had been under the treatment of various physicians
for a numbness in the fourth and fifth fingers of his left hand. These
physicians had been treating this condition by applications of poultices
to the hand itself. Galen, being called in consultation, pointed out
that the injury was probably not in the hand itself, but in the ulner
nerve, which controls sensation in the fourth and fifth fingers. Surmising
that the nerve must have been injured in some way, he made careful
inquiries of the patient, who recalled that he had been thrown from
his chariot some time before, striking and injuring his back. Acting
upon this information, Galen applied stimulating remedies to the source
of the nerve itself---that is, to the bundle of nerve-trunks known
as the brachial plexus, in the shoulder. To the surprise and confusion
of his fellow-physicians, this method of treatment proved effective
and the patient recovered completely in a short time.

Although the functions of the organs in the chest were not well understood
by Galen, he was well acquainted with their anatomy. He knew that
the lungs were covered by thin membrane, and that the heart was surrounded
by a sac of very similar tissue. He made constant comparisons also
between these organs in different animals, as his \textit{\emph{dissections}}
were performed upon beasts ranging in size from a mouse to an elephant.
The minuteness of his observations is shown by the fact that he had
noted and described the ring of bone found in the hearts of certain
animals, such as the horse, although not found in the human heart
or in most animals.

His description of the abdominal organs was in general accurate. He
had noted that the abdominal cavity was lined with a peculiar saclike
membrane, the peritoneum, which also surrounded most of the organs
contained in the cavity, and he made special note that this membrane
also enveloped the liver in a peculiar manner. The exactness of the
last observation seems the more wonderful when we reflect that even
to-day the medical student finds a correct understanding of the position
of the folds of the peritoneum one of the most difficult subjects
in anatomy.

%
\begin{figure}
\noindent \begin{center}\includegraphics[  width=1.0\columnwidth]{1hsci10-Wil1S280}\end{center}

\noindent \begin{center}\noun{\small Galen}\end{center}{\small \par}

\noindent \begin{center}\emph{\footnotesize (From an old print.)}\end{center}
\end{figure}
As a practical physician he was held in the highest esteem by the
Romans. The Emperor Marcus Aurelius called him to Rome and appointed
him physician-inordinary to his son Commodus, and on special occasions
Marcus Aurelius himself called in Galen as his medical adviser. On
one occasion, the three army surgeons in attendance upon the emperor
declared that he was about to be attacked by a fever. Galen relates
how {}``on special command I felt his pulse, and finding it quite
normal, considering his age and the time of day, I declared it was
no fever but a digestive disorder, due to the food he had eaten, which
must be converted into phlegm before being excreted. Then the emperor
repeated three times, `That's the very thing,'\ and asked what was
to be done. I answered that I usually gave a glass of wine with pepper
sprinkled on it, but for you kings we only use the safest remedies,
and it will suffice to apply wool soaked in \textit{\emph{hot}} \emph{}\textit{\emph{nard}}
ointment locally. The emperor ordered the wool, wine, \textit{etc}.,
to be brought, and I left the room. His feet were warmed by rubbing
with hot hands, and after drinking the peppered wine, he said to Pitholaus
(his son's tutor), `We have only one doctor, and that an honest one,'\ and
went on to describe me as the first of physicians and the only philosopher,
for he had tried many before who were not only lovers of money, but
also contentious, ambitious, envious, and malignant.''%
\footnote{\emph{Ibid}.%
}

It will be seen from this that Galen had a full appreciation of his
own abilities as a physician, but inasmuch as succeeding generations
for a thousand years concurred in the alleged statement made by Marcus
Aurelius as to his ability, he is perhaps excusable for his open avowal
of his belief in his powers. His faith in his accuracy in diagnosis
and prognosis was shown when a colleague once said to him, {}``I
have used the prognostics of Hippocrates as well as you. Why can I
not prognosticate as well as you?''\ To this Galen replied, {}``By
God's help I have never been deceived in my prognosis.''%
\footnote{Johann Hermann Bass, \emph{History of Medicine}, New York, 1889.%
} It is probable that this statement was made in the heat of argument,
and it is hardly to be supposed that he meant it literally.

His systems of treatment were far in advance of his theories regarding
the functions of organs, causes of disease, \textit{etc}., and some
of them are still first principles with physicians. Like Hippocrates,
he laid great stress on correct diet, exercise, and reliance upon
nature. {}``Nature is the overseer by whom health is supplied to
the sick,''\ he says. {}``Nature lends her aid on all sides, she
decides and cures diseases. No one can be saved unless nature conquers
the disease, and no one dies unless nature succumbs.''

From the picture thus drawn of Galen as an anatomist and physician,
one might infer that he should rank very high as a scientific exponent
of medicine, even in comparison with modern physicians. There is,
however, another side to the picture. His knowledge of anatomy was
certainly very considerable, but many of his deductions and theories
as to the functions of organs, the cause of diseases, and his methods
of treating them, would be recognized as absurd by a modern school-boy
of average intelligence. His greatness must be judged in comparison
with ancient, not with modern, scientists. He maintained, for example,
that respiration and the pulse-beat were for one and the same purpose---that
of the reception of air into the arteries of the body. To him the
act of breathing was for the purpose of admitting air into the lungs,
whence it found its way into the heart, and from there was distributed
throughout the body by means of the arteries. The skin also played
an important part in supplying the body with air, the pores absorbing
the air and distributing it through the arteries. But, as we know
that he was aware of the fact that the arteries also contained blood,
he must have believed that these vessels contained a mixture of the
two.

Modern anatomists know that the heart is divided into two approximately
equal parts by an impermeable septum of tough fibres. Yet, Galen,
who dissected the hearts of a vast number of the lower animals according
to his own account, maintained that this septum was permeable, and
that the air, entering one side of the heart from the lungs, passed
through it into the opposite side and was then transferred to the
arteries.

He was equally at fault, although perhaps more excusably so, in his
explanation of the action of the nerves. He had rightly pointed out
that nerves were merely connections between the brain and spinal-cord
and distant muscles and organs, and had recognized that there were
two kinds of nerves, but his explanation of the action of these nerves
was that {}``nervous spirits''\ were carried to the cavities of
the brain by blood-vessels, and from there transmitted through the
body along the nerve-trunks.

In the human skull, overlying the nasal cavity, there are two thin
plates of bone perforated with numerous small \textit{\emph{apertures}}\emph{.}
\textit{\emph{These}} \emph{}\textit{\emph{apertures}} allow the passage
of numerous nerve-filaments which extend from a group of cells in
the brain to the delicate membranes in the nasal cavity. These perforations
in the bone, therefore, are simply to allow the passage of the nerves.
But Galen gave a very different explanation. He believed that impure
{}``animal spirits''\ were carried to the cavities of the brain
by the arteries in the neck and from there were sifted out through
these perforated bones, and so expelled from the body.

He had observed that the skin played an important part in cooling
the body, but he seems to have believed that the heart was equally
active in overheating it. The skin, therefore, absorbed air for the
purpose of {}``cooling the heart,''\ and this cooling process was
aided by the brain, whose secretions aided also in the cooling process.
The heart itself was the seat of courage; the brain the seat of the
rational soul; and the liver the seat of love.

The greatness of Galen's teachings lay in his knowledge of anatomy
of the organs; his weakness was in his interpretations of their functions.
Unfortunately, succeeding generations of physicians for something
like a thousand years rejected the former but clung to the latter,
so that the advances he had made were completely overshadowed by the
mistakes of his teachings.


\chapter*{\raggedright XI. A RETROSPECTIVE GLANCE AT CLASSICAL SCIENCE}

\addcontentsline{toc}{chapter}{XI. A RETROSPECTIVE GLANCE AT\\
CLASSICAL SCIENCE}

\markboth{A HISTORY OF SCIENCE, BOOK I}{XI. A RETROSPECTIVE GLANCE}

It is a favorite tenet of the modern historian that history is a continuous
stream. The contention has fullest warrant. Sharp lines of demarcation
are an evidence of man's analytical propensity rather than the work
of nature. Nevertheless it would be absurd to deny that the stream
of history presents an ever-varying current. There are times when
it seems to rush rapidly on; times when it spreads out into a broad---seemingly
static---current; times when its catastrophic changes remind us of
nothing but a gigantic cataract. Rapids and whirlpools, broad estuaries
and tumultuous cataracts are indeed part of the same stream, but they
are parts that vary one from another in their salient features in
such a way as to force the mind to classify them as things apart and
give them individual names.

So it is with the stream of history; however strongly we insist on
its continuity we are none the less forced to recognize its periodicity.
It may not be desirable to fix on specific dates as turning-points
to the extent that our predecessors were wont to do. We may not, for
example, be disposed to admit that the Roman Empire came to any such
cataclysmic finish as the year 476 A.D., when cited in connection
with the overthrow of the last Roman Empire of the West, might seem
to indicate. But, on the other hand, no student of the period can
fail to realize that a great change came over the aspect of the historical
stream towards the close of the Roman epoch.

The span from Thales to Galen has compassed about eight hundred years---let
us say thirty generations. Throughout this period there is scarcely
a generation that has not produced great scientific thinkers---men
who have put their mark upon the progress of civilization; but we
shall see, as we look forward for a corresponding period, that the
ensuing thirty generations produced scarcely a single scientific thinker
of the first rank. Eight hundred years of intellectual activity---thirty
generations of greatness; then eight hundred years of stasis---thirty
generations of mediocrity; such seems to be the record as viewed in
perspective. Doubtless it seemed far different to the contemporary
observer; it is only in reasonable perspective that any scene can
be viewed fairly. But for us, looking back without prejudice across
the stage of years, it seems indisputable that a great epoch came
to a close at about the time when the barbarian nations of Europe
began to sweep down into Greece and Italy. We are forced to feel that
we have reached the limits of progress of what historians are pleased
to call the ancient world. For about eight hundred years Greek thought
has been dominant, but in the ensuing period it is to play a quite
subordinate part, except in so far as it influences the thought of
an alien race. As we leave this classical epoch, then, we may well
recapitulate in brief its triumphs. A few words will suffice to summarize
a story the details of which have made up our recent chapters.

In the field of cosmology, Greek genius has demonstrated that the
earth is spheroidal, that the moon is earthlike in structure and much
smaller than our globe, and that the sun is vastly larger and many
times more distant than the moon. The actual size of the earth and
the angle of its axis with the ecliptic have been measured with approximate
accuracy. It has been shown that the sun and moon present inequalities
of motion which may be theoretically explained by supposing that the
earth is not situated precisely at the centre of their orbits. A system
of eccentrics and epicycles has been elaborated which serves to explain
the apparent motions of the heavenly bodies in a manner that may be
called scientific even though it is based, as we now know, upon a
false hypothesis. The true hypothesis, which places the sun at the
centre of the planetary system and postulates the orbital and axial
motions of our earth in explanation of the motions of the heavenly
bodies, has been put forward and ardently championed, but, unfortunately,
is not accepted by the dominant thinkers at the close of our epoch.
In this regard, therefore, a vast revolutionary work remains for the
thinkers of a later period. Moreover, such observations as the precession
of the \textit{\emph{equinoxes}} and the moon's evection are as yet
unexplained, and measurements of the earth's size, and of the sun's
size and distance, are so crude and imperfect as to be in one case
only an approximation, and in the other an absurdly inadequate suggestion.
But with all these defects, the total achievement of the Greek astronomers
is stupendous. To have clearly grasped the idea that the earth is
round is in itself an achievement that marks off the classical from
the Oriental period as by a great gulf.

In the physical sciences we have seen at least the beginnings of great
things. Dynamics and hydrostatics may now, for the first time, claim
a place among the sciences. Geometry has been perfected and trigonometry
has made a sure beginning. The conception that there are four elementary
substances, earth, water, air, and fire, may not appear a secure foundation
for chemistry, yet it marks at least an attempt in the right direction.
Similarly, the conception that all matter is made up of indivisible
particles and that these have adjusted themselves and are perhaps
held in place by a whirling motion, while it is scarcely more than
a scientific dream, is, after all, a dream of marvellous insight.

In the field of biological science progress has not been so marked,
yet the elaborate garnering of facts regarding anatomy, physiology,
and the zoological sciences is at least a valuable preparation for
the generalizations of a later time.

If with a map before us we glance at the portion of the globe which
was known to the workers of the period now in question, bearing in
mind at the same time what we have learned as to the seat of labors
of the various great scientific thinkers from Thales to Galen, we
cannot fail to be struck with a rather startling fact, intimations
of which have been given from time to time---the fact, namely, that
most of the great Greek thinkers did not live in Greece itself. As
our eye falls upon Asia Minor and its outlying islands, we reflect
that here were born such men as Thales, Anaximander, Anaximenes, Heraclitus,
Pythagoras, Anaxagoras, Socrates, Aristarchus, Hipparchus, Eudoxus,
Philolaus, and Galen. From the northern shores of the \AE{}gean came
Lucippus, Democritus, and Aristotle. Italy, off to the west, is the
home of Pythagoras and Xenophanes in their later years, and of Parmenides
and Empedocles, Zeno, and Archimedes. Northern Africa can claim, by
birth or by adoption, such names as Euclid, \textit{\emph{Apollonius}}
of Perga, Herophilus, Erasistratus, Aristippus, Eratosthenes, Ctesibius,
Hero, Strabo, and Ptolemy. This is but running over the list of great
men whose discoveries have claimed our attention. Were we to extend
the list to include a host of workers of the second rank, we should
but emphasize the same fact.

All along we are speaking of Greeks, or, as they call themselves,
\textit{\emph{Hellenes}}, and we mean by these words the people whose
home was a small jagged peninsula jutting into the Mediterranean at
the southeastern extremity of Europe. We think of this peninsula as
the home of Greek culture, yet of all the great thinkers we have just
named, not one was born on this peninsula, and perhaps not one in
five ever set foot upon it. In point of fact, one Greek thinker of
the very first rank, and one only, was born in Greece proper; that
one, however, was Plato, perhaps the greatest of them all. With this
one brilliant exception (and even he was born of parents who came
from the provinces), all the great thinkers of Greece had their origin
at the circumference rather than the centre of the empire. And if
we reflect that this circumference of the Greek world was in the nature
of the case the widely circling region in which the Greek came in
contact with other nations, we shall see at once that there could
be no more striking illustration in all history than that furnished
us here of the value of racial mingling as a stimulus to intellectual
progress.

But there is one other feature of the matter that must not be overlooked.
Racial mingling gives vitality, but to produce the best effect the
mingling must be that of races all of which are at a relatively high
plane of civilization. In Asia Minor the Greek mingled with the Semite,
who had the heritage of centuries of culture; and in Italy with the
Umbrians, Oscans, and Etruscans, who, little as we know of their antecedents,
have left us monuments to testify to their high development. The chief
reason why the racial mingling of a later day did not avail at once
to give new life to Roman thought was that the races which swept down
from the north were barbarians. It was no more possible that they
should spring to the heights of classical culture than it would, for
example, be possible in two or three generations to produce a racer
from a stock of draught horses. Evolution does not proceed by such
vaults as this would imply. Celt, Goth, Hun, and Slav must undergo
progressive development for many generations before the population
of northern Europe can catch step with the classical Greek and prepare
to march forward. That, perhaps, is one reason why we come to a period
of stasis or retrogression when the time of classical activity is
over. But, at best, it is only one reason of several.

The influence of the barbarian nations will claim further attention
as we proceed. But now, for the moment, we must turn our eyes in the
other direction and give attention to certain phases of Greek and
of Oriental thought which were destined to play a most important part
in the development of the Western mind---a more important part, indeed,
in the early medi\ae{}val period than that played by those important
inductions of science which have chiefly claimed our attention in
recent chapters. The subject in question is the old familiar one of
false inductions or pseudoscience. In dealing with the early development
of thought and with Oriental science, we had occasion to emphasize
the fact that such false inductions led everywhere to the prevalence
of superstition. In dealing with Greek science, we have largely ignored
this subject, confining attention chiefly to the progressive phases
of thought; but it must not be inferred from this that Greek science,
with all its secure inductions, was entirely free from superstition.
On the contrary, the most casual acquaintance with Greek literature
would suffice to show the incorrectness of such a supposition. True,
the great thinkers of Greece were probably freer from this thraldom
of false inductions than any of their predecessors. Even at a very
early day such men as Xenophanes, Empedocles, Anaxagoras, and Plato
attained to a singularly rationalistic conception of the universe.

We saw that {}``the father of medicine,''\ Hippocrates, banished
demonology and conceived disease as due to natural causes. At a slightly
later day the sophists challenged all knowledge, and Pyrrhonism became
a synonym for scepticism in recognition of the leadership of a master
doubter. The entire school of Alexandrians must have been relatively
free from superstition, else they could not have reasoned with such
effective logicality from their observations of nature. It is almost
inconceivable that men like Euclid and Archimedes, and Aristarchus
and Eratosthenes, and Hipparchus and Hero, could have been the victims
of such illusions regarding occult forces of nature as were constantly
postulated by Oriental science. Herophilus and Erasistratus and Galen
would hardly have pursued their anatomical studies with equanimity
had they believed that ghostly apparitions watched over living and
dead alike, and exercised at will a malign influence.

Doubtless the Egyptian of the period considered the work of the Ptolemaic
anatomists an unspeakable profanation, and, indeed, it was nothing
less than revolutionary---so revolutionary that it could not be sustained
in subsequent generations. We have seen that the great Galen, at Rome,
five centuries after the time of Herophilus, was prohibited from dissecting
the human subject. The fact speaks volumes for the attitude of the
Roman mind towards science. Vast audiences made up of every stratum
of society thronged the amphitheatre, and watched exultingly while
man slew his fellow-man in single or in multiple combat. Shouts of
frenzied joy burst from a hundred thousand throats when the death-stroke
was given to a new victim. The bodies of the slain, by scores, even
by hundreds, were dragged ruthlessly from the arena and hurled into
a ditch as contemptuously as if pity were yet unborn and human life
the merest bauble. Yet the same eyes that witnessed these scenes with
ecstatic approval would have been averted in pious horror had an anatomist
dared to approach one of the mutilated bodies with the scalpel of
science. It was sport to see the blade of the gladiator enter the
quivering, living flesh of his fellow-gladiator; it was joy to see
the warm blood spurt forth from the writhing victim while he still
lived; but it were sacrilegious to approach that body with the knife
of the anatomist, once it had ceased to pulsate with life. Life itself
was held utterly in contempt, but about the realm of death hovered
the threatening ghosts of superstition. And such, be it understood,
was the attitude of the Roman populace in the early and the most brilliant
epoch of the empire, before the Western world came under the influence
of that Oriental philosophy which was presently to encompass it.

In this regard the Alexandrian world was, as just intimated, far more
advanced than the Roman, yet even there we must suppose that the leaders
of thought were widely at variance with the popular conceptions. A
few illustrations, drawn from Greek literature at various ages, will
suggest the popular attitude. In the first instance, consider the
poems of Homer and of Hesiod. For these writers, and doubtless for
the vast majority of their readers, not merely of their own but of
many subsequent generations, the world is peopled with a multitude
of invisible apparitions, which, under title of gods, are held to
dominate the affairs of man. It is sometimes difficult to discriminate
as to where the Greek imagination drew the line between fact and allegory;
nor need we attempt to analyse the early poetic narratives to this
end. It will better serve our present purpose to cite three or four
instances which illustrate the tangibility of beliefs based upon pseudo-scientific
inductions.

Let us cite, for example, the account which Herodotus gives us of
the actions of the Greeks at Plat\ae{}a, when their army confronted
the remnant of the army of Xerxes, in the year 479 B.C. Here we see
each side hesitating to attack the other, merely because the oracle
had declared that whichever side struck the first blow would lose
the conflict. Even after the Persian soldiers, who seemingly were
a jot less superstitious or a shade more impatient than their opponents,
had begun the attack, we are told that the Greeks dared not respond
at first, though they were falling before the javelins of the enemy,
because, forsooth, the entrails of a fowl did not present an auspicious
appearance. And these were Greeks of the same generation with Empedocles
and Anaxagoras and \AE{}schylus; of the same epoch with Pericles
and Sophocles and Euripides and Phidias. Such was the scientific status
of the average mind---nay, of the best minds---with here and there
a rare exception, in the golden age of Grecian culture.

Were we to follow down the pages of Greek history, we should but repeat
the same story over and over. We should, for example, see Alexander
the Great balked at the banks of the Hyphasis, and forced to turn
back because of inauspicious auguries based as before upon the dissection
of a fowl. Alexander himself, to be sure, would have scorned the augury;
had he been the prey of such petty superstitions he would never have
conquered Asia. We know how he compelled the oracle at Delphi to yield
to his wishes; how he cut the Gordian knot; how he made his dominating
personality felt at the temple of Ammon in Egypt. We know, in a word,
that he yielded to superstitions only in so far as they served his
purpose. Left to his own devices, he would not have consulted an oracle
at the banks of the Hyphasis; or, consulting, would have forced from
the oracle a favorable answer. But his subordinates were mutinous
and he had no choice. Suffice it for our present purpose that the
oracle was consulted, and that its answer turned the conqueror back.

One or two instances from Roman history may complete the picture.
Passing over all those mythical narratives which virtually constitute
the early history of Rome, as preserved to us by such historians as
Livy and Dionysius, we find so logical an historian as Tacitus recording
a miraculous achievement of Vespasian without adverse comment. {}``During
the months when Vespasian was waiting at Alexandria for the periodical
season of the summer winds, and a safe navigation, many miracles occurred
by which the favor of Heaven and a sort of bias in the powers above
towards Vespasian were manifested.'' Tacitus then describes in detail
the cure of various maladies by the emperor, and relates that the
emperor on visiting a temple was met there, in the spirit, by a prominent
Egyptian who was proved to be at the same time some eighty miles distant
from Alexandria.

It must be admitted that Tacitus, in relating that Vespasian caused
the blind to see and the lame to walk, qualifies his narrative by
asserting that {}``persons who are present attest the truth of the
transaction when there is nothing to be gained by falsehood.'' Nor
must we overlook the fact that a similar belief in the power of royalty
has persisted almost to our own day. But no such savor of scepticism
attaches to a narrative which Dion Cassius gives us of an incident
in the life of Marcus Aurelius---an incident that has become famous
as the episode of The Thundering Legion. Xiphilinus has preserved
the account of Dion, adding certain picturesque interpretations of
his own. The original narrative, as cited, asserts that during one
of the northern campaigns of Marcus Aurelius, the emperor and his
army were surrounded by the hostile Quadi, who had every advantage
of position and who presently ceased hostilities in the hope that
heat and thirst would deliver their adversaries into their hands without
the trouble of further fighting. {}``Now,''\ says Dion, {}``while
the Romans, unable either to combat or to retreat, and reduced to
the last extremity by wounds, fatigue, heat, and thirst, were standing
helplessly at their posts, clouds suddenly gathered in great number
and rain descended in floods---certainly not without divine intervention,
since the Egyptian Maege Arnulphis, who was with Marcus Antoninus,
is said to have invoked several genii by the aerial mercury by enchantment,
and thus through them had brought down rain.''

Here, it will be observed, a supernatural explanation is given of
a natural phenomenon. But the narrator does not stop with this. If
we are to accept the account of Xiphilinus, Dion brings forward some
striking proofs of divine interference. Xiphilinus gives these proofs
in the following remarkable paragraph:\ 

{}``Dion adds that when the rain began to fall every soldier lifted
his head towards heaven to receive the water in his mouth; but afterwards
others hold out their shields or their helmets to catch the water
for themselves and for their horses. Being set upon by the barbarians\ \ldots{}\ while
occupied in drinking, they would have been seriously incommoded had
not heavy hail and numerous thunderbolts thrown consternation into
the ranks of the enemy. Fire and water were seen to mingle as they
left the heavens. The fire, however, did not reach the Romans, but
if it did by chance touch one of them it was immediately extinguished,
while at the same time the rain, instead of comforting the barbarians,
seemed merely to excite like oil the fire with which they were being
consumed. Some barbarians inflicted wounds upon themselves as though
their blood had power to extinguish flames, while many rushed over
to the side of the Romans, hoping that there water might save them.''

We cannot better complete these illustrations of pagan credulity than
by adding the comment of Xiphilinus himself. That writer was a Christian,
living some generations later than Dion. He never thought of questioning
the facts, but he felt that Dion's interpretation of these facts must
not go unchallenged. As he interprets the matter, it was no pagan
magician that wrought the miracle. He even inclines to the belief
that Dion himself was aware that Christian interference, and not that
of an Egyptian, saved the day. {}``Dion knew,''\ he declares, {}``that
there existed a legion called The Thundering Legion, which name was
given it for no other reason than for what came to pass in this war,''\ and
that this legion was composed of soldiers from Militene who were all
professed Christians. {}``During the battle,''\ continues Xiphilinus,
{}``the chief of the Pretonians had set at Marcus Antoninus, who
was in great perplexity at the turn events were taking, representing
to him that there was nothing the people called Christians could not
obtain by their prayers, and that among his forces was a troop composed
wholly of followers of that religion. Rejoiced at this news, Marcus
Antoninus demanded of these soldiers that they should pray to their
god, who granted their petition on the instant, sent lightning among
the enemy and consoled the Romans with rain. Struck by this wonderful
success, the emperor honored the Christians in an edict and named
their legion The Thundering. It is even asserted that a letter existed
by Marcus Antoninus on this subject. The pagans well knew that the
company was called The Thunderers, having attested the fact themselves,
but they revealed nothing of the occasion on which the leader received
the name.''%
\footnote{Dion Cassius, as preserved by Xiphilinus. Our extract is quoted from
the translation given in \emph{The Historians'\ History of the World}
(edited by Henry Smith Williams), 25 \textit{\emph{vols}}., London
and New York, 1904, Vol.\ VI., p.\ 297 \textit{ff}.%
}

Peculiar interest attaches to this narrative as illustrating both
credulousness as to matters of fact and pseudo-scientific explanation
of alleged facts. The modern interpreter may suppose that a violent
thunderstorm came up during the course of a battle between the Romans
and the so-called barbarians, and that owing to the local character
of the storm, or a chance discharge of lightning, the barbarians suffered
more than their opponents. We may well question whether the philosophical
emperor himself put any other interpretation than this upon the incident.
But, on the other hand, we need not doubt that the major part of his
soldiers would very readily accept such an explanation as that given
by Dion Cassius, just as most readers of a few centuries later would
accept the explanation of Xiphilinus. It is well to bear this thought
in mind in considering the static period of science upon which we
are entering. We shall perhaps best understand this period, and its
seeming \textit{\emph{retrogressions}}, \textit{\emph{if}} we suppose
that the average man of the Middle Ages was no more credulous, no
more superstitious, than the average Roman of an earlier period or
than the average Greek; though the precise complexion of his credulity
had changed under the influence of Oriental ideas, as we have just
seen illustrated by the narrative of Xiphilinus.


\chapter*{\raggedright APPENDIX: NOTES}

\addcontentsline{toc}{chapter}{APPENDIX: NOTES}

\markboth{A HISTORY OF SCIENCE, BOOK I}{APPENDIX: NOTES}


\section*{\raggedright CHAPTER I.\ PREHISTORIC SCIENCE}

Length of the Prehistoric Period.---It is of course quite impossible
to reduce the prehistoric period to any definite number of years.
There are, however, numerous bits of evidence that enable an anthropologist
to make rough estimates as to the relative lengths of the different
periods into which prehistoric time is divided. Gabriel de Mortillet,
one of the most industrious students of prehistoric arch\ae{}ology,
ventured to give a tentative estimate as to the numbers of years involved
in each period. He of course claimed for this nothing more than the
value of a scientific guess. It is, however, a guess based on a very
careful study of all data at present available. Mortillet divides
the prehistoric period, as a whole, into four epochs. The first of
these is the preglacial, which he estimates as comprising seventy-eight
thousand years; the second is the glacial, covering one hundred thousand
years; then follows what he terms the Solutreen, which numbers eleven
thousand years; and, finally, the Magdalenien, comprising thirty-three
thousand years. This gives, for the prehistoric period proper, a term
of about two hundred and twenty-two thousand years. Add to this perhaps
twelve thousand years ushering in the civilization of Egypt, and the
six thousand years of stable, sure chronology of the historical period,
and we have something like two hundred and thirty thousand or two
hundred and forty thousand years as the age of man.

{}``These figures,''\ says Mortillet, {}``are certainly not exaggerated.
It is even probable that they are below the truth. Constantly new
discoveries are being made that tend to remove farther back the date
of man's appearance.'' We see, then, according to this estimate,
that about a quarter of a million years have elapsed since man evolved
to a state that could properly be called human. This guess is as good
as another, and it may advantageously be kept in mind, as it will
enable us all along to understand better than we might otherwise be
able to do the tremendous force of certain prejudices and preconceptions
which recent man inherited from his prehistoric ancestor. Ideas which
had passed current as unquestioned truths for one hundred thousand
years or so are not easily cast aside.

In going back, in imagination, to the beginning of the prehistoric
period, we must of course reflect, in accordance with modern ideas
on the subject, that there was no year, no millennium even, when it
could be said expressly: {}``This being was hitherto a primate, he
is now a man.'' The transition period must have been enormously long,
and the changes from generation to generation, even from century to
century, must have been very slight. In speaking of the extent of
the age of man this must be borne in mind: it must be recalled that,
even if the period were not vague for other reasons, the vagueness
of its beginning must make it indeterminate.

Bibliographical Notes.---A great mass of literature has been produced
in recent years dealing with various phases of the history of prehistoric
man. No single work known to the writer deals comprehensively with
the scientific attainments of early man; indeed, the subject is usually
ignored, except where practical phases of the mechanical arts are
in question. But of course any attempt to consider the condition of
primitive man takes into account, by inference at least, his knowledge
and attainments. Therefore, most works on anthropology, ethnology,
and primitive culture may be expected to throw some light on our present
subject. Works dealing with the social and mental conditions of existing
savages are also of importance, since it is now an accepted belief
that the ancestors of civilized races evolved along similar lines
and passed through corresponding stages of nascent culture. Herbert
Spencer's \emph{Descriptive Sociology} presents an unequalled mass
of facts regarding existing primitive races, but, unfortunately, its
inartistic method of arrangement makes it repellent to the general
reader. E.\ B.\ Tyler's \emph{Primitive Culture and Anthropology};
Lord Avebury's \emph{Prehistoric Times}, \emph{The Origin of Civilization},
and \emph{The Primitive Condition of Man}; W.\ Boyd Dawkin's \emph{Cave-Hunting
and Early Man in Britain}; and Edward Clodd's \emph{Childhood of the
World} and \emph{Story of Primitive Man} are deservedly popular. Paul
Topinard's \emph{Elements d'Anthropologie Generale} is one of the
best-known and most comprehensive French works on the technical phases
of anthropology; but Mortillet's \textit{Le} \textit{Pr\'{e}historique}
has a more popular interest, owing to its chapters on primitive industries,
though this work also contains much that is rather technical. Among
periodicals, the \emph{Revue de l'Ecole d'Anthropologie de Paris},
published by the professors, treats of all phases of anthropology,
and the \emph{American Anthropologist}, edited by F.\ W.\ Hodge
for the American Anthropological Association, and intended as {}``a
medium of communication between students of all branches of anthropology,''\ contains
much that is of interest from the present stand-point. The last-named
journal devotes a good deal of space to Indian languages.


\section*{\raggedright CHAPTER II. EGYPTIAN SCIENCE}

The most accessible recent sources of information as to the social
conditions of the ancient Egyptians are the works of Maspero and Erman,
above mentioned; and the various publications of W.\ M.\ Flinders
Petrie, \emph{The Pyramids and Temples of} \textit{Gizeh}, London,
1883; \emph{Tanis I}., London, 1885; \emph{Tanis H., Nebesheh, and
Defe-nnel}, London, 1887; \emph{Ten Years'\ Diggings}, London, 1892;
Syria and Egypt from the \emph{}\textit{Tel}-\textit{el}-\textit{Amar}-\textit{na}
\emph{Letters}, London, 1898, \textit{etc}. The various works of Professor
Petrie, recording his explorations from year to year, give the fullest
available insight into Egyptian arch\ae{}ology.


\section*{\raggedright CHAPTER III. SCIENCE OF BABYLONIA AND ASSYRIA}

Of the books mentioned above,%
\footnote{\emph{I.e.}, in the footnotes---R.B.%
} that of Hommel is particularly full in reference to culture development;
Goodspeed's small volume gives an excellent condensed account; the
original documents as translated in the various volumes of \emph{Records
of the Past} are full of interest; and Menant's little book is altogether
admirable. The work of excavation is still going on in old Babylonia,
and newly discovered texts add from time to time to our knowledge,
but A.\ H.\ Layard's \emph{Nineveh and its Remains} (London, 1849)\ still
has importance as a record of the most important early discoveries.
The general histories of Antiquity of Duncker, Lenormant, Maspero,
and Meyer give full treatment of Babylonian and Assyrian development.
Special histories of Babylonia and Assyria, in addition to these named
above, are Tiele's \textit{Babylonisch}-\emph{Assyrische} \textit{Geschichte}
(\textit{\emph{Zwei}} Tiele, Gotha, 1886-1888); Winckler's \textit{Geschichte}
\emph{Babyloniens} \textit{und} Assyriens (Berlin, 1885-1888), and
Rogers'\ \emph{History of Babylonia and Assyria}, New York and London,
1900, the last of which, however, deals almost exclusively with political
history. Certain phases of science, particularly with reference to
chronology and cosmology, are treated by Edward \textit{\emph{Meyer}}
(\textit{Geschichte} \textit{des} \emph{Alterthum}, Vol.\ I., Stuttgart,
1884), and by P.\ Jensen (\emph{Die} \textit{Kosmologie} \textit{der}
\textit{Babylonier}, \textit{\emph{Strassburg}}, 1890), but no comprehensive
specific treatment of the subject in its entirety has yet been attempted.


\section*{\raggedright CHAPTER IV. THE DEVELOPMENT OF THE ALPHABET}

For facsimiles of the various scripts, see Henry Smith Williams' \emph{History
of the Art Of Writing}, 4 \textit{\emph{vols}}, New York and London,
1902-1903.
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