_An Address delivered July 7, 1875, at the Opening of the Summer
Courses of Instruction in Chemistry, at Harvard University._
You have come together this morning to begin various elementary courses
of instruction in chemistry and mineralogy. As I have been informed,
most of you are teachers by profession, and your chief object is to
become acquainted with the experimental methods of teaching physical
science, and to gain the advantages in your study which the large
apparatus of this university is capable of affording.
In all this I hope you will not be disappointed. You, as teachers, know
perfectly well that success must depend, first of all, on your own
efforts; but, since the methods of studying Nature are so different from
those with which you are familiar in literary studies, I feel that the
best service I can render, in this introductory address, is to state,
as clearly as I can, the great objects which should be kept in view in
the courses on which you are now entering.
By your very attendance on these courses you have given the strongest
evidence of your appreciation of the value of chemical studies as a part
of the system of education, and let me say, in the first place, that you
have not overvalued their importance. The elementary principles and more
conspicuous facts of chemistry are so intimately associated with the
experience of every-day life, and find such important applications in
the useful arts, that no man at the present day can be regarded as
educated who is ignorant of them. Not to know why the fire burns, or how
the sulphur trade affects the industries of the world, will be regarded,
by the generation of men among whom your pupils will have to win their
places in society, as a greater mark of ignorance than a false quantity
in Latin prosody or a solecism in grammar.
Moreover, I need not tell you that physical science has become a great
power in the world. Indeed, after religion, it is the greatest power of
our modern civilization. Consider how much it has accomplished during
the last century toward increasing the comforts and enlarging the
intellectual vision of mankind. The railroad, the steamship, the
electric telegraph, photography, gaslights, petroleum oils, coal-tar
colors, chlorine bleaching, anaesthesia, are a few of its recent
material gifts to the world; and not only has it made one pair of hands
to do the work of twenty, but it has so improved and facilitated the old
industries that what were luxuries to the fathers of our republic have
become necessities to our generation.
And when, passing from these material fruits, you consider the purely
intellectual triumphs of physical science, such as those which have been
gained with the telescope, the microscope, and the spectroscope, you can
not wonder at the esteem in which these branches of study are held in
this practical age of the world.
Now, these immense results have been gained by the application to the
study of Nature of a method which was so admirably described by Lord
Bacon in his "Novum Organon," and which is now generally called the
experimental method. What we observe in Nature is an orderly succession
of phenomena. The ancients speculated about these phenomena as well as
ourselves, but they contented themselves with speculations, animating
Nature with the products of their wild fancies. Their great master,
Aristotle, has never been excelled in the art of dialectics; but his
method of logic applied to the external world was of very necessity an
utter failure. It is frequently said, in defense of the exclusive study
of the records of ancient learning, that they are the products of
thinking, loving, and hating men, like ourselves, and it is claimed that
the study of science can never rise to the same nobility because it
deals only with lifeless matter. But this is a mere play on words, a
repetition of the error of the old schoolmen.
Physical science is noble because it does deal with thought, and with
the very noblest of all thought. Nature at once manifests and conceals
an Infinite Presence: her methods and orderly successions are the
manifestations of Omnipotent Will; her contrivances and laws the
embodiment of Omniscient Thought. The disciples of Aristotle so signally
failed simply because they could see in Nature only a reflection of
their idle fancies. The followers of Bacon have so gloriously succeeded
because they approached Nature as humble students, and, having first
learned how to question her, have been content to be taught and not
sought to teach. The ancient logic never relieved a moment of pain, or
lifted an ounce of the burden of human misery. The modern logic has made
a very large share of material comfort the common heritage of all
civilized men.
In what, then, does this Baconian system consist? Simply in these
elements: 1. Careful observation of the conditions under which a given
phenomenon occurs; 2. The varying of these conditions by experiments,
and observing the effects produced by the variation. We thus find that
some of the conditions are merely accidental circumstances, having no
necessary connection with the phenomenon, while others are its
invariable antecedent. Having now discovered the true relations of the
phenomenon we are studying, a happy guess, suggested probably by
analogy, furnishes us with a clew to the real causes on which it
depends. We next test our guess by further experiments. If our
hypothesis is true, this or that must follow; and, if in all points the
theory holds, we have discovered the law of which we are in search. If,
however, these necessary inferences are not realized, then we must
abandon our hypothesis, make another guess, and test that in its turn.
Let me illustrate by two well-known examples:
The, of old, universally accepted principle that all living organisms
are propagated by seeds or germs (_omnia ex ovo_) has been seriously
questioned by a modern school of naturalists. Various observers have
maintained that there were conditions under which the lower forms of
organic life were developed independently of all such accessories, but
other, and equally competent, naturalists, who have attempted to
investigate the subject, have obtained conflicting results.
Thus it was observed that certain low forms of life were quite
constantly developed in beef juice that had been carefully prepared and
hermetically sealed in glass flasks, even after these flasks had been
exposed for a long time to the temperature of boiling water. "Here,"
proclaims the new school, "is unmistakable evidence of spontaneous
generation; for, if past experience is any guide, all germs must have
been killed by the boiling water." "No," answer the more cautious
naturalists, "you have not yet proved your point. You have no right to
assume that all germs are killed at this temperature."
The experiments, therefore, were repeated under various conditions and
at different temperatures, but with unsatisfactory results, until
Pasteur, a distinguished French physicist, devised a very simple mode of
testing the question. He reasoned thus: "If, as is generally believed,
the presence of invisible spores in the air is an essential condition of
the development of these lower growths, then their production must bear
some proportion to the abundance of these spores. Near the habitations
of animals and plants, where the spores are known to be in abundance,
the development would be naturally at a maximum, and we should expect
that the growth would diminish in proportion as the microscope indicated
that the spores diminished in the atmosphere."
Accordingly, Pasteur selected a region in the Jura Mountains suitable
for his purpose, and repeated the well-known experiment with beef juice,
first at the inn of a town at the foot of the mountains, and then at
various elevations up to the bare rocks which covered the top of the
ridge, a height of some eight thousand feet. At each point he sealed up
beef juice in a large number of flasks, and watched the result. He found
that while in the town the animalcules were developed in almost all the
flasks, they appeared only in two or three out of a hundred cases where
the flasks had been sealed at the top of the mountain, and to a
proportionate extent in those sealed at the intermediate elevations.
What, now, did these experiments prove? Simply this, that the
development of these organic forms was in direct proportion to the
number of germs in the air. It did not settle the question of
spontaneous generation, but it showed that false conclusions had been
deduced from the experiments which had been cited to prove it.
A still more striking illustration of the same method of questioning
Nature is to be found in the investigation of Sir Humphry Davy, on the
composition of water. The voltaic battery which works our telegraphs was
invented by Volta in 1800; and later, during the same year, it was
discovered in London, by Nicholson and Carlisle, that this remarkable
instrument had the power of decomposing water. These physicists at once
recognized that the chief products of the action of the battery on water
were hydrogen and oxygen gases, thus confirming the results of
Cavendish, who, in 1781, had obtained water by combining these
elementary substances; oxygen having been previously discovered in 1775,
and hydrogen, at least, as early as 1766. It was, however, very soon
also observed that there were always formed by the action of the battery
on water, besides these aeriform products, an alkali and an acid, the
alkali collecting around the negative pole, and the acid around the
positive pole of the electrical combination. In regard to the nature of
this acid and alkali, there was the greatest difference of opinion among
the early experimenters on this subject. Cruickshanks supposed that the
acid was nitrous acid, and the alkali ammonia. Desormes, a French
chemist, attempted to prove that the acid was muriatic acid; while
Brugnatelli asserted that a new and peculiar acid was formed, which he
called the electric acid.
It was in this state of the question that Sir Humphry Davy began his
investigation. From the analogies of chemical science, as well as from
the previous experiments of Cavendish and Lavoisier, he was persuaded
that water consisted solely of oxygen and hydrogen gases, and that the
acid and alkali were merely adventitious products. This opinion was
undoubtedly well founded; but, great disciple of Bacon as he was, Davy
felt that his opinion was worth nothing unless substantiated by
experimental evidence, and accordingly he set himself to work to obtain
the required proof.
In Davy's first experiments the two glass tubes which he used to contain
the water were connected together by an animal membrane, and he found,
on immersing the poles of his battery in their respective tubes, that,
besides the now well-known gases, there were really formed muriatic acid
in one tube, and a fixed alkali in the other. Davy at once, however,
suspected that the acid and alkali came from common salt contained in
the animal membrane, and he therefore rejected this material and
connected the glass tubes by carefully washed cotton fiber, when, on
submitting the water as before to the action of the voltaic current, and
continuing the experiment through a great length of time, no _muriatic_
acid appeared; but he still found that the water in the one tube was
strongly alkaline, and in the other strongly acid, although the acid was
chiefly, at least, nitrous acid. A part of the acid evidently came from
the animal membrane, but not the whole, and the source of the alkali was
as obscure as before.
Davy then made another guess. He knew that alkali was used in the
manufacture of glass; and it occurred to him that the glass of the
tubes, decomposed by the electric current, might be the origin of the
alkali in his experiments. He therefore substituted for the glass tubes
cups of agate, which contains no alkali, and repeated the experiment,
but still the troublesome acid and alkali appeared. Nevertheless, he
said, it is possible that these products may be derived from some
impurities existing in the agate cups, or adhering to them; and so, in
order to make his experiments as refined as possible, he rejected the
agate vessels and procured two conical cups of pure gold, but, on
repeating the experiments, the acid and alkali again appeared.
And now let me ask who is there of us who would not have concluded at
this stage of the inquiry that the acid and alkali were essential
products of the decomposition of water? But not so with Davy. He knew
perfectly well that all the circumstances of his experiments had not
been tested, and until this had been done he had no right to draw such a
conclusion. He next turned to the water he was using. It was distilled
water, which he supposed to be pure, but still, he said, it is possible
that the impurities of the spring-water may be carried over to a slight
extent by the steam in the process of distillation, and may therefore
exist in my distilled water to a sufficient amount to have caused the
difficulty. Accordingly, he evaporated a quart of this water in a silver
dish, and obtained seven-tenths of a grain of dry residue. He then added
this residue to the small amount of water in the gold cones and again
repeated the experiment. The proportion of alkali and acid was sensibly
increased.
You think he has found at last the source of the acid and alkali in the
impurities of the water. So thought Davy, but he was too faithful a
disciple of Bacon to leave this legitimate inference unverified.
Accordingly, he repeatedly distilled the water from a silver alembic
until it left absolutely no residue on evaporation, and then with water
which he knew to be pure, and contained in vessels of gold from which he
knew it could acquire no taint, he still again repeated the already
well-tried experiment. He dipped his test-paper into the vessel
connected with the positive pole, and the water was still decidedly
acid. He dipped the paper into the vessel connected with the negative
pole, and the water was still alkaline.
You might well think that Davy would have been discouraged here. But not
in the least. The path to the great truths which Nature hides often
leads through a far denser and a more bewildering forest than this; but
then there is not infrequently a "blaze" on the trees which points out
the way, although it may require a sharp eye in a clear head to see the
marks. And Davy was well enough trained to observe a circumstance which
showed that he was now on the right path and heading straight for the
goal.
On examining the alkali formed in this last experiment, he found that
it was not, as before, a fixed alkali, soda or potash, but the volatile
alkali ammonia. Evidently the fixed alkali came from the impurities of
the water, and when, on repeating the experiment with pure water in
agate cups or glass tubes, the same results followed, he felt assured
that so much at least had been established. There was still, however,
the production of the volatile alkali and of nitrous acid to be
accounted for. As these contain only the elements of air and water, Davy
thought that possibly they might be formed by the combination of
hydrogen at the one pole and of oxygen at the other with the nitrogen of
the air, which was necessarily dissolved in the water. In order,
therefore, to eliminate the effect of the air, he again repeated the
experiment under the receiver of an air-pump from which the atmosphere
had been exhausted, but still the acid and alkali appeared in the two
cups.
Davy, however, was not discouraged by this, for the "blazes" on the
trees were becoming more numerous, and he now felt sure that he was fast
approaching the end. He observed that the quantity of acid and alkali
had been greatly diminished by exhausting the air, and this was all that
could be expected, for, as Davy knew perfectly well, the best air-pumps
do not remove all the air. He therefore, for the last experiment, not
only exhausted the air, but replaced it with pure hydrogen, and then
exhausted the hydrogen and refilled the receiver with the same gas
several times in succession, until he was perfectly sure that the last
traces of air had been as it were washed out. In this atmosphere of pure
hydrogen he allowed the battery to act on the water, and not until the
end of twenty-four hours did he disconnect the apparatus. He then dips
his test-paper into the water connected with the positive pole, and
there is no trace of acid; he dips it into the water at the negative
pole, and there is no alkali; and you may judge with what satisfaction
he withdraws those slips of test-paper, whose unaltered surfaces showed
that he had been guided at last to the truth, and that his perseverance
had been rewarded.
The fame of Sir Humphry Davy rests on his discovery of the metals of the
alkalies and earths which first revealed the wonderful truth that the
crust of our globe consists of metallic cinders; but none of these
brilliant results show so great scientific merit or such eminent power
of investigating Nature as the experiments which I have just detailed. I
have not, however, described them here for the purpose of glorifying
that renowned man. His honored memory needs no such office at my hands.
My only object was to show you what is meant by the Baconian method of
science, and to give some idea of the nature of that modern logic which
within the last fifty years has produced more wonderful transformations
in human society than the author of Aladdin ever imagined in his wildest
dreams. In this short address I can of course give you but a very dim
and imperfect idea of what I have called the Baconian system of
experimental reasoning. Indeed, you can not form any clear conception of
it, until in some humble way you have attempted to use the method, each
one for himself, and you have come here in order that you may acquire
such experience.
My object, however, will be gained if these illustrations serve to give
emphasis to the following statements, which I feel I ought to make at
the opening of these courses of instruction--statements which have an
especial appropriateness in this place, since I am addressing teachers,
who are in a position to exert an important influence on the system of
education in this country.
In the first place, then, I must declare my conviction that no educated
man can expect to realize his best possibilities of usefulness without a
practical knowledge of the methods of experimental science. If he is to
be a physician, his whole success will depend on the skill with which he
can use these great tools of modern civilization. If he is to be a
lawyer, his advancement will in no small measure be determined by the
acuteness with which he can criticise the manner in which the same tools
have been used by his own or his opponent's clients. If he is to be a
clergyman, he must take sides in the great conflict between theology and
science which is now raging in the world, and, unless he wishes to play
the part of the doughty knight Don Quixote, and think he is winning
great victories by knocking down the imaginary adversaries which his
ignorance has set up, he must try the steel of his adversary's blade.
Let me be fully understood. It is not to be expected or desired that
many of our students should become professional men of science. The
places of employment for scientific men are but few, and more in the
future than in the past they will naturally be secured by those whom
Nature has endowed with special aptitudes or tastes--usually the signs
of aptitudes--to investigate her laws. That our country will always
offer an honorable career to her men of genius, we have every reason to
expect, and these born students of Nature will usually follow the plain
indications of Providence without encouragement or direction from us.
It is different, however, with the great body of earnest students who
are conscious of no special aptitudes, but who are desirous of doing the
best thing to fit themselves for usefulness in the world; and I feel
that any system of education is radically defective which does not
comprise a sufficient training in the methods of experimental science
to make the mass of our educated men familiar with this tool of modern
civilization: so that, when, hereafter, new conquests over matter are
announced and great discoveries are proclaimed, they may be able not
only to understand but also to criticise the methods by which the
assumed results have been reached, and thus be in a position to
distinguish between the true and the false. Whether we will or not, we
must live under the direction of this great power of modern society, and
the only question is whether we will be its ignorant slave or its
intelligent servant.
In the second place, it seems fitting that I should state to you what I
regard as the true aims to be kept in view in a course of scientific
study, and to give my reasons for the methods we have adopted in
arranging the courses you are about beginning.
In our day there has arisen a warm discussion as to the relative claims
of two kinds of culture, and attempts are made to create an antagonism
between them. But all culture is the same in spirit. Its object is to
awaken and strengthen the powers of the mind; for these, like the
muscles of the body, are developed and rendered strong and active only
by exercise; while, on the other hand, they may become atrophied from
mere want of use. Science culture differs in its methods from the old
classical culture, but it has the same spirit and the same object. You
must not, therefore, expect me to advocate the former at the expense of
the latter; for, although I have labored assiduously during a quarter of
a century to establish the methods of science teaching which have now
become general, I am far from believing that they are the only true
modes of obtaining a liberal education. So far from this, if it were
necessary to choose one of two systems, I should favor the classical;
and why?
Language is the medium of thought, and can not be separated from it. He
who would think well must have a good command of language, and he who
has the best command of language I am almost tempted to say will think
the best. For this reason a certain amount of critical study of language
is essential for every educated man, and such study is not likely to be
gained except through the great ancient languages; the advocates of
classical scholarship frequently say, can not be gained. I am not ready
to accept this dictum; but I most willingly concede that in the present
state of our schools it is not likely to be gained. I never had any
taste myself for classical studies; but I know that I owe to the study a
great part of the mental culture which has enabled me to do the work
that has fallen to my share in life.
But, while I concede all this, I do not believe, on the other hand, that
the classical is the only effective method of culture; you evidently do
not think so, for you would not be here if you did. But, in abandoning
the old tried method, which is known to be good, for the new, you must
be careful that you gain the advantages which the new offers; and you
will not gain the new culture you seek unless you study science in the
right way. In the classical departments the methods are so well
established, and have been so long tested by experience, that there can
hardly be a wrong way. But in science there is not only a wrong way, but
this wrong way is so easy and alluring that you will most certainly
stray into it unless you strive earnestly to keep out of it. Hence I am
most anxious to point out to you the right way, and do what I can to
keep you in it; and you will find that our courses and methods have been
devised with this object.
When advocating in our mother University of Cambridge, in Old England,
the claims of scientific culture, I was pushed with an argument which
had very great weight with the eminent English scholars present, and
which you will be surprised to learn was regarded as fatal to the
success of the science "triposes" then under debate. The argument was
that the experimental sciences could not be made the subjects of
competitive examinations. Some may smile at such an objection; but, as
viewed from the English standpoint, there was really a great deal in it,
and the argument brought out the radical difference between scientific
and classical culture.
The old method of culture may be said to have culminated in the
competitive examinations of the English universities. We have no such
examinations here. Success depends not simply on knowing your subject
thoroughly, but on having it at your fingers' ends, and those fingers so
agile that they can accomplish not only a prodigious amount of work in a
short time, but can do this work with absolute accuracy. For the only
approach we make to an experience of this kind, we must look to our
athletic contests. It may of course be doubted whether the ability, once
in a man's life, to perform such mental feats, is worth what it costs.
Still it implies a very high degree of mental culture, and it is
perfectly certain that the experimental sciences give no field for that
sort of mental prize-fights. It is easy to prepare written examinations
which will show whether the students have been faithful to their work,
but they can not be adapted to such competitions as I have described
without abandoning the true object of science culture. The ability of
the scientific student can only be shown by long-continued work at the
laboratory table, and by his success in investigating the problems which
Nature presents.
We have here struck the true key-note of the scientific method. The
great object of all our study should be to study Nature, and all our
methods should be directed to this one object. This aim alone will
ennoble our scholarship as students, and will give dignity to our
scientific calling as men of science. It is this high aim, moreover,
which vindicates the worth of the mode of culture we have chosen. What
is it that ennobles literary culture but the great minds which, through
this culture, have honored the nations to which they belong?
The culture we have chosen is capable of even greater things; not
because science is nobler than art, for both are equally noble--it is
the thought, the conception, which ennobles, and I care not whether it
be attained through one kind of exercise of the mental faculties or
another--but we are capable of grander and nobler thoughts than Plato,
Cicero, Shakespeare, or Newton, because we live in a later period of the
world's history, when, through science, the world has become richer in
great ideas. It is, I repeat, the great thought which ennobles, and it
ennobles because it raises to a higher plane that which is immortal in
our manhood.
If I have made my meaning clear, and if you sympathize with my feelings,
you will understand why I regard culture as so important to the
individual and to the nation. The works of Shakespeare and of Bacon are
of more value to England to-day than the memories of Blenheim or
Trafalgar; and those great minds will still be living powers in the
world when Marlborough and Nelson are only remembered as historical
names.
I therefore believe that it is the first duty of a country to foster the
highest culture, and that it should be the aim of every scholar to
promote this culture both by his own efforts and his active influence. A
nation can become really great in no other way. We live in a country of
great possibilities; and the danger is that, as with many men I have
known in college, of great potential abilities, the greatness will end
where it begins. The scholars of the country should have but one voice
in this matter, and urge upon the government and upon individuals the
duty of encouraging and supporting mental culture for its own sake.
The time has passed when we can afford to limit the work of our higher
institutions of learning to teaching knowledge already acquired.
Henceforth the investigation of unsolved problems, and the discovery of
new truth, should be one of the main objects at our American
universities, and no cost grudged which is required to maintain at them
the most active minds, in every branch of knowledge which the country
can be stimulated to produce.
I could urge this on the self-interest of the nation as an obvious
dictate of political economy. I could say, and say truly, that the
culture of science will help us to develop those latent resources of
which we are so proud; will enable us to grow two blades of grass where
one grew before; to extract a larger percentage of metal from our ores;
to economize our coal, and in general to direct our waiting energies so
that they may produce a more abundant pecuniary reward. I could tell of
Galvani studying for twenty long years, to no apparent purpose, the
twitching of frogs' hind-legs, and thus sowing the seed from which has
sprung the greatest invention of modern times. Or, if our Yankee
impatience would be unwilling to wait half a century for the fruit to
ripen, I could point to the purely theoretical investigations of organic
chemistry, which in less than five years have revolutionized one of the
great industries of Europe, and liberated thousands of acres for a more
beneficent agriculture. This is all true, and may be urged properly if
higher considerations will not prevail. It is an argument I have used in
other places, but I will not use it here; although I gladly acknowledge
the Providence which brings at last even material fruits to reward
conscientious labor for the advancement of knowledge and the
intellectual elevation of mankind. I would rather point to that far
greater multitude who worked in faith for the love of knowledge, and who
ennobled themselves and ennobled their nation, not because they added to
its material prosperity, but because they made themselves and made their
fellows more noble men.
I come back now again to the moral of all this, to urge upon you, as
the noblest patriotism and the most enlightened self-interest, the duty
of striving for yourselves and encouraging in others the highest culture
in the studies you have chosen, and this culture with one end in view,
to advance knowledge. I am far, of course, from advising you to grapple
immaturely with unsolved problems, or, when you have gained the
knowledge with which you can dare to venture from the beaten track, to
undertake work beyond your power. Many a young scientific man has
suffered the fate of Icarus in attempting to soar too high. Moreover, I
am far from expecting that all or many of you will ever have the
opportunity of going beyond the well-explored fields of knowledge; but
you can all have the aim, and that aim will make your work more worthy
and more profitable to yourselves. Every American boy can not be
President of the United States, but if, as our English cousins allege,
he believes that he can be, the very belief makes him an abler man.
We have dwelt long enough on these generalities, and it is time to come
down to commonplaces, and to inquire what are the essential conditions
of this scientific culture which shall fit us to investigate Nature; and
the first thought that occurs to me in this connection may be expressed
thus: Science presents to us two aspects, which I may call its objective
and its subjective aspect. Objectively it is a body of facts, which we
have to observe, and subjectively it is a body of truths, conclusions,
or inferences, deduced from these facts; and the two sides of the
subject should always be kept in view.
I propose next to say a few words in regard to each of these two aspects
of our study, and in regard to the best means of training our faculties
so as to work successfully in each sphere. First, then, success in the
observation of phenomena implies three qualities at least, namely,
quickness and sharpness of perception, accuracy in details, and
truthfulness; and on its power to cultivate these qualities a large part
of the value of science, as a means of education, depends.
To begin with the cultivation of our perceptions. We are all gifted with
senses, but how few of us use them to the best advantage! "We have eyes
and see not"; for, although the light paints the picture on the retina,
our dull perceptions give no attention to the details, and we retain
only a confused impression of what has passed before our eyes. "But
how," you may ask, "are we to cultivate this sharpness of perception?" I
answer, only by making a conscious effort to fix our attention on the
objects we study until the habit becomes a second nature. I have often
noticed, with surprise, the power which uneducated miners frequently
possess of recognizing many minerals at sight. This they have acquired
by long experience and close familiarity with such objects, and such
power of observation is with them so purely a habit that they are
frequently unable to state clearly the grounds on which their
conclusions are based. They recognize the minerals by what in common
language is called their "looks" and they notice delicate differences in
the "looks" to which most men are blind. It is, however, the business of
the scientific mineralogist to analyze these "looks," and to point out
in what the differences consist; so that by fixing his attention on
these points the student may gain, by a few hours' study, the power
which the miner acquires only after long experience.
The chief difficulty, however, which we find in teaching mineralogy is,
that the students do not readily see the differences when they are
pointed out, or, if they see them, do not remember them with sufficient
precision to render their subsequent observations conclusive and
precise. This either arises from a failure to cultivate the powers of
observation in childhood, or the subsequent blunting of them by disuse.
The ladies will scout the idea that a brooch of cut-glass is as
ornamental as one of diamond, and yet I venture to assert that there is
not one person in fifty, at least of those who have not made a study of
the subject, who can tell the difference between the two. The external
appearance depends simply on what we call lustre. The lustre of glass
is vitreous, that of the diamond adamantine; and I know of no other
distinction which it is more difficult for students to recognize than
this. Those of you who study mineralogy will experience this difficulty,
and it can be overcome only by giving careful attention to the subject.
The teacher can do nothing more than put in your hands the specimens
which illustrate the point, and you must study these specimens until you
see the difference. It is a question of sight, not of understanding, and
all the optical theories of the cause of the lustre will not help you in
the least toward seeing the difference between diamond and glass, or
anglesite and heavy spar.
Another illustration of the same fact is the constant failure of
students to distinguish by the eye alone between the two minerals called
copper-glance and gray copper. There is a difference of color and lustre
which, although usually well marked, it requires an educated eye to
distinguish.
Mineralogy undoubtedly demands a more careful cultivation of the
perceptions than the other branches of chemistry; but still you will
find abundant practice for close observation in them all. I have often
known students to reach erroneous results in qualitative analysis by
mistaking a white precipitate in a colored liquid for a colored
precipitate, or by not attending to similar broad distinctions, which
would have been obvious to any careful observer; and so in quantitative
analysis, mere delicacy of touch or handling is a great element of
success.
But I must pass on to speak of the importance in the study of Nature of
accuracy in detail, which is the second condition of successful
observation of which I spoke. We must cultivate not only accuracy in
observing details, but also accuracy in following details which have
been laid down by others for our guidance. In science we can not draw
correct conclusions from our premises unless we are sure that we have
all the facts, and what seemed at first an unimportant detail often
proves to be the determining condition of the result; and, again, if we
are told that under certain conditions a certain sign is the proof of
the presence of a certain substance, we have no right to assume that the
sign is of any value unless the conditions are fulfilled. A black
precipitate, for example, obtained under certain conditions, is a proof
of the presence of nickel, but we can not assert that we have found
nickel unless we have followed out those details in every particular.
Of course, we must avoid empiricism as far as we can. We must seek to
learn the reasons of the details, and such knowledge will not only
render our work intelligent, but will also frequently enable us to
judge how far the details are essential, and to what extent our
processes may be varied with safety. We must also avoid trifling, and,
above all, "the straining at a gnat and swallowing a camel," as is the
habit with triflers. Large knowledge and good judgment will avoid all
such errors; but, if we must choose between fussiness and carelessness,
the first is the least evil. Slovenly work means slovenly results, and
habits of carefulness, neatness, and order produce as excellent fruits
in the laboratory as in the home.
Last in order but first in importance of the conditions of successful
observation, mentioned above, stands truthfulness. Here you may think I
am approaching a delicate subject, of which even to speak might seem to
cast a reproach. But not so at all. I am not speaking here of conscious
deception, for I assume that no one who aspires to be a student of
Nature can be guilty of that. But I am speaking of a quality whose
absence is not necessarily a mark of sinfulness, but whose possession,
in a high degree, is a characteristic of the greatest scientific talent.
As every lawyer knows, he is a rare man whose testimony is not colored
by his interests, and a very large amount of self-deception is
compatible with conscious honesty of purpose.
So among scientific students the power to keep the mind unbiased, and
not to color our observations in the least degree, is one of the rarest
as it is one of the noblest of qualities. It is a quality we must strive
after with all our might, and we shall not attain it unless we strive.
Remember, our observations are our data, and, unless accurate,
everything deduced from them must have the taint of our deception. We
can not deceive Nature, however much we may deceive ourselves; and there
is many a student who would cut off his right hand rather than be guilty
of a conscious untruth, who is yet constantly untruthful to himself.
Every year students of mineralogy present to me written descriptions of
mineral specimens which particularize, as observed, characters that do
not appear on the specimen given them to determine, although they may be
the correct characters of some other mineral.
There is usually no want of honesty in this, but, deceived by some
accident, the student has made a wrong guess, and then imagined that he
saw on the specimen those characters which he knew from the descriptions
ought to appear on the assumed mineral. So, also, it not unfrequently
happens that a student in qualitative analysis, who has obtained some
hints in regard to the composition of his solution, will torture his
observations until they seem to him to confirm his erroneous inferences;
and again the student in quantitative analysis, who finds out the exact
weight he ought to obtain, is often insensibly influenced by this
knowledge--in the washing and ignition of his precipitate, or in some
other way--and thus obtains results whose only apparent fault may be a
too close agreement with theory, but which, nevertheless, are not
accurate because not true. It is evident how fatal such faults as these
must be to the investigation of truth, and they are equally destructive
of all scientific scholarship. Their effect on the student is so marked
that, although he may deceive himself, he will rarely deceive his
teacher. That he should lose confidence in his own results is, to the
teacher, one of the most marked indications of such false methods of
study, but the student usually refers his want of success to any cause
but the real one--his own untruthfulness. He will complain of the
teacher, or of the methods of instruction, and may even persuade himself
that all scientific results are as uncertain as his own. As I have said,
mere ordinary truthfulness, which spurns any conscious deception, will
not save us from falling into such faults. Our scientific study demands
a much higher order of truthfulness than this. We should so love the
truth above all price as to strive for it with single-hearted and
unswerving purpose. We must be constantly on our guard to avoid any
circumstance which would tend to bias our minds or warp our judgments,
and we must make the attainment of the truth our sole motive, guide, and
end.
It remains for me, before closing this address, to say a few words on
what I have called the subjective aspect of scientific study. Science
offers us not only a mass of phenomena to be observed, but also a body
of truths which have been deduced from these observations; and, without
the power of drawing correct inferences from the data acquired, exact
observations would be of little value. I have already described the
inductive method of reasoning, and illustrated it by two noteworthy
examples, and, in a humbler measure, we must apply the same method in
our daily work in the laboratory. We must learn how to vary our
experiments so as to eliminate the accidental circumstances, and make
evident the essential conditions of the phenomena we are studying. Such
power can only be acquired by practice, and a somewhat long experience
in active teaching has convinced me that there is no better means of
training this logical faculty than the study of qualitative chemical
analysis in which many of you are to engage.
The results of the processes of qualitative analysis are perfectly
definite and trustworthy; but they are only reached by following out the
indications of experiments which are frequently obscure, and even
apparently contradictory; reconciling by new experiments the seeming
discrepancies, and, at last, having eliminated all other possible causes
of the phenomena observed, discovering the true nature of the
substances under examination.
The study of mineralogy affords an almost equally good practice,
although in a somewhat different form. By comparing carefully many
specimens of the same mineral, you learn to distinguish the accidental
from the essential characters, and on this distinction you must base
your inferences in regard to the nature of the specimens you may be
called upon to determine. A single remark occurs to me which may aid you
in cultivating this scientific logic.
Do not attempt to reason on insufficient data. Multiply your
observations or experiments, and when your premises are ample, the
conclusion will generally take care of itself. Are you in doubt in
regard to a mineral specimen? Repeat your observations again and again,
multiply them with the aid of the blow-pipe or goniometer, compare the
specimen with known specimens which it resembles, until either your
doubts are removed or you are satisfied that you are unequal to the
task; and remember that, in many cases, the last is the only honest
conclusion.
Are you in doubt in regard to the reactions of the substance you are
analyzing, whether they are really those of a metal you suspect to be
present? Do not rest in such a frame of mind, and, above all, do not try
to remove the doubt by comparing your experience with that of your
neighbor, but multiply your own experiments; procure some compound of
the metal, and compare its reactions with those you have observed until
you reach either a positive or a negative result.
Remember that the way to remove your doubts is to widen your own
knowledge, and not to depend on the knowledge of others. When your
knowledge of the facts is ample, your inferences will be satisfactory,
and then an unexplained phenomenon is the guide to a new discovery. Do
not be discouraged if you have to labor long in the dark before the day
begins to dawn. It will at last dawn to you, as it has dawned to others
before, and, when the morning breaks, you will be satisfied with the
result of your labor.
Moreover, I feel confident that such experience will very greatly tend
to increase your appreciation of the value of scientific studies in
training the reasoning faculties of the mind. This, as every one must
admit, is the best test of their utility in a scheme of education, and
it is precisely here that I claim for them the very highest place. It
has generally been admitted that mathematical studies are peculiarly
well adapted to train the logical faculties, but still many persons have
maintained that, since the mathematics deal wholly with absolute
certainties, an exclusive devotion to this class of subjects unfits the
mind for weighing the probable evidence by which men are chiefly guided
in the affairs of life.
But, without attempting to discuss this question, on which much might be
said on both sides, it is certain that no such objection can be urged
against the study of the physical sciences if conducted in the manner I
have attempted to describe. These subjects present to the consideration
of the student every degree of probable evidence, accustoming him to
weigh all the evidence for or against a given conclusion, and to reject
or to provisionally accept only on the balance of probabilities.
Moreover, in practical science, the student is taught to follow out a
chain of probable evidence with care and caution, to eliminate all
accidental phenomena, and supply, by experiment or observation, the
missing links, until he reaches the final conclusion--an intellectual
process which, though based wholly on probable evidence, may have all
the force and certainty of a mathematical demonstration.
Indeed, that highly valued scientific acumen and skill which enables the
student to brush away the accidental circumstances by which the laws of
Nature are always concealed until the truth stands out in bold relief,
is but a higher phase of the same talent which marks professional skill
in all the higher walks of life. The physician who looks through the
external symptoms of his patient to the real disease which lurks
beneath; the lawyer, who disentangles a mass of conflicting testimony,
and follows out the truth successfully to the end; the statesman, who
sees beneath the froth of political life the great fundamental
principles which will inevitably rule the conduct of the state, and thus
foresees and provides for the coming change; the general, who discovers
amid the confusion of the battlefield the weak point of his enemy's
front; the merchant, even, who can interpret the signs of the unsettled
market--employ the same faculty, and frequently in not a much lower
degree, that discovered the law of gravitation, and which, since the
days of Newton, has worked so successfully to unveil the mysteries of
the material creation.
Moreover, I hope, my friends, that you will come to value scientific
studies, not simply because they cultivate the perceptive and reasoning
faculties, but also because they fill the mind with lofty ideals,
elevated conceptions, and noble thoughts. Indeed, I claim that there is
no better school in which to train the aesthetical faculties of the mind,
the tastes, and the imagination, than the study of natural science.
The beauty of Nature is infinite, and the more we study her works the
more her loveliness unfolds. The upheaved mountain, with its mantle of
eternal snow; the majestic cataract, with its whirl and roar of waters;
the sunset cloud, with its blending of gorgeous hues, lose nothing of
their beauty for him who knows the mystery they conceal. On the
contrary, they become, one and all, irradiated by the Infinite Presence
which shines through them, and fill the mind with grander conceptions
and nobler ideas than your uneducated child of Nature could ever attain.
Remember that I am not recommending an exclusive devotion to the natural
sciences. I am only claiming for them their proper place in the scheme
of education, and I do not, of course, deny the unquestionable value of
both the ancient and the modern classics in cultivating a pure and
elevated taste. But I do say that the poet-laureate of England has drawn
a deeper inspiration from Nature interpreted by science than any of his
predecessors of the classical school; and I do also affirm that the
pre-Raphaelite school of painting, with all its grotesque mimicry of
Nature, embodies a truer and purer ideal than that of any Roman fable or
Grecian dream.
And what shall we say of the imagination? Where can you find a wider
field for its exercise than that opened by the discoveries of modern
science? And as the mind wanders over the vast expanse, crossing
boundless spaces, dwelling in illimitable time, witnessing the displays
of immeasurable power, and studying the adaptations of Omniscient
skill, it lives in a realm of beauty, of wonder, and of awe, such as no
artist has ever attained to in word, in sound, in color, or in form. And
if such a life does not lead man to feel his own dependence, to yearn
toward the Infinite Father, and to rest on the bosom of Infinite Love,
it is simply because it is not the noble in intellect, not the great in
talent, not the profound in knowledge, not the rich in experience, not
the lofty in aspiration, not the gifted in imagery, but solely the pure
in heart, who see God.
Such, then, is a very imperfect presentation of what I believe to be the
value of scientific studies as a means of education. In what I have
stated I have implied that, for these studies to be of any real value,
the end must be constantly kept in view, and everything made subservient
to the one great object.
To study the natural sciences merely as a collection of interesting
facts which it is well for every educated man to know, seldom serves a
useful purpose. The young mind becomes wearied with the details, and
soon forgets what it has never more than half acquired. The lessons
become an exercise of the memory and of nothing more; and if, as is too
frequently the case, an attempt is made to cram the half-formed mind in
a single school-year with an epitome of half the natural
sciences--natural philosophy, astronomy, and chemistry, physiology,
zooelogy, botany, and mineralogy, following each other in rapid
succession--these studies become a great evil, an actual nuisance, which
I should be the first to vote to abate. The tone of mind is not only not
improved, but seriously impaired, and the best product is a superficial,
smattering smartness, which is the crying evil not only of our schools
but also of our country.
In order that the sciences should be of value in our educational system,
they must be taught more from things than from books, and never from
books without the things. They must be taught, also, by real living
teachers, who are themselves interested in what they teach, are
interested also in their pupils, and understand how to direct them
aright. Above all, the teachers must see to it that their pupils study
with the understanding, and not solely with the memory, not permitting a
single lesson to be recited which is not thoroughly understood, taking
the greatest care not to load the memory with any useless lumber, and
eschewing merely memorized rules as they would deadly poison. The great
difficulty against which the teachers of natural science have to contend
in the colleges are the wretched tread-mill habits the students bring
with them from the schools. Allow our students to memorize their
lessons, and they will appear respectably well, but you might as easily
remove a mountain as to make many of them think. They will solve an
involved equation of algebra readily enough so long as they can do it by
turning their mental crank, when they will break down on the simplest
practical problem of arithmetic which requires of them only thought
enough to decide whether they shall multiply or divide.
Many a boy of good capabilities has been irretrievably ruined, as a
scholar, by being compelled to learn the Latin grammar by rote at an age
when he was incapable of understanding it; and I fear that schools may
still be found where young minds are tortured by this stupefying
exercise. Those of us who have faith in the educational value of
scientific studies are most anxious that the students who resort to our
colleges should be as well fitted in the physical sciences as in the
classics, for otherwise the best results of scientific culture can not
be expected. As it is, our students come to the university, not only
with no preparation in physical science, but with their perceptive and
reasoning faculties so undeveloped that the acquisition of the
elementary principles of science is burdensome and distasteful; and good
scholars, who are ambitious of distinction, can more readily win their
laurels on the old familiar track than on an untried course of which
they know nothing, and for which they must begin their training anew.
We have improved our system of instruction in the college as fast as we
could obtain the means, but we are persuaded that the best results can
not be reached without the cooeperation of the schools. We feel,
therefore, that it is incumbent upon us, in the first place, to do
everything in our power to prove to the teachers of this country how
great is the educational value of the physical sciences, when properly
taught; and secondly, to aid them in acquiring the best methods of
teaching these subjects. It is with such aims that our summer courses
have been instituted, and your presence here in such numbers is the best
evidence that they have met a real want of the community. We welcome you
to the university and to such advantages as it can afford, and we shall
do all in our power to render your brief residence here fruitful, both
in experience and in knowledge; hoping, also, that the university may
become to you, as she has to so many others, a bright light shining
calmly over the troubled sea of active life, ever suggesting lofty
thoughts, encouraging noble endeavors, and inciting all her children to
work together toward those great ends, the advancement of knowledge and
the education of mankind.