about from place to place, eating now here and now there and then making
selection, from one motive or another, but presumably following the
dictates of its own taste or fancy. What does it not do? First, it does
not, from choice, eat anything bad. Secondly, it does not necessarily
consume all of its food in this way. If it finds a particularly choice
spot, it may confine its feeding to that spot; or, if its owner sees fit,
he may remove it to the stable, where it may stand all day and eat what he
chooses to give it. The benefits of browsing are, first, the nourishment
actually derived from the food taken, coupled with the fact that it is
taken in small quantities, and in great variety; and secondly, the
knowledge of good spots, obtained from the testing of one spot after
another, throughout the whole broad pasture.

Now I submit that our figure of speech holds good in all these
particulars. The literary "browser" partakes of his mental food from books
and is thereby nourished and stimulated; he takes it here and there in
brief quantities, moving from section to section and from shelf to shelf,
selecting choice morsels of literature as fancy may dictate. He does not,
if he is a healthy reader, absorb voluntarily anything that will hurt him,
and this method of literary absorption does not preclude other methods of
mental nourishment. He may like a book so much that he proceeds to devour
it whole, or his superiors in knowledge may remove him to a place where
necessary mental food is administered more or less forcibly. And having
gone so far with our comparison, we shall make no mistake if we go a
little further and say that the benefits of browsing to the reader are
twofold, as they are to the material feeder--the absorption of actual
nutriment in his own wilful, wayward manner--a little at a time and in
great variety; and the knowledge of good reading obtained from such a wide
testing of the field.

Are not these real benefits, and are they not desirable? I fear that our
original surmise was correct and that browsing is condemned not for what
it does, but because it fails to do something that it could not be
expected to do. Of course, if one were to browse continuously he would be
unable to feed in any other way. Attendance upon school or the continuous
reading of any book whatever would be obviously impossible. To avoid
misunderstanding, therefore, we will agree at this point that whatever may
be said here in commendation of browsing is on condition that it be
occasional and not excessive and that the normal amount of continuous
reading and study proceed together with it.

Having settled, therefore, that browsing is a good thing when one does not
occupy ones' whole time with it, let us examine its advantages a little
more in detail.

First: about the mental nourishment that is absorbed in browsing; the
specific information, the appreciation of what is good, the intellectual
stimulation--not that which comes from reading suggested or guided by
browsing, but from the actual process itself. I have heard it strenuously
denied that any such absorption occurs; the bits taken are too small, the
motion of the browser is too rapid, the whole process is too desultory.
Let us see. In the first place a knowledge of authors and titles and of
the general character of their works is by no means to be despised. I
heard the other day of a presumably educated woman who betrayed in a
conversation her ignorance of Omar Khayyam--not lack of acquaintance with
his works, but lack of knowledge that such a person had ever existed. If
at some period in her life she had held in her hand a copy of "The
Rubaiyat," and had glanced at its back, without even opening it, how much
embarrassment she might have been spared! And if, in addition, she had
glanced within for just ten seconds and had discovered that he wrote
poetry in stanzas of four lines each, she would have known as much about
Omar as do many of those who would contemptuously scoff at her ignorance.
With so brief effort may we acquire literary knowledge sufficient to avoid
embarrassment in ordinary conversation. Browsing in a good library, if the
browser has a memory, will soon equip him with a wide range of knowledge
of this kind. Nor is such knowledge to be sneered at as superficial. It is
all that we know, or need to know, about scores of authors. One may never
study higher mathematics, but it may be good for him to know that Lagrange
was a French author who wrote on analytical mechanics, that Euclid was a
Greek geometer, and that Hamilton invented quaternions. All this and
vastly more may be impressed on the mind by an hour in the mathematical
alcove of a library of moderate size. And it will do no harm to a boy to
know that Benvenuto Cellini wrote his autobiography, even if the
inevitable perusal of the book is delayed for several years, or that
Felicia Hemans, James Thomson, and Robert Herrick wrote poetry,
independently of familiarity with their works, or that "Lamia" is not
something to eat or "As you like it" a popular novel. Information of this
kind is almost impossible to acquire from lists or from oral statement,
whereas a moment's handling of a book in the concrete may fix it in the
mind for good and all. So far, we have not supposed that even a word of
the contents has been read. What, now, if a sentence, a stanza, a
paragraph, a page, passes into the brain through the eye? Those who
measure literary effect by the thousand words or by the hour are making a
great mistake. The lightning flash is over in a fraction of a second, but
in that time it may reveal a scene of beauty, may give the traveller
warning of the fatal precipice, or may shatter the farmer's home into
kindling wood. Intellectual lightning may strike the "browser" as he
stands there book in hand before the shelf. A word, a phrase, may sear
into his brain--may turn the current of his whole life. And even if no
such epoch-making words meet his eye, in how brief a time may he read,
digest, appreciate, some of the gems of literature! Leigh Hunt's "Jennie
kissed me" would probably take about thirty seconds; on a second reading
he would have it by heart--the joy of a life-time. How many meaty epigrams
would take as long? The whole of Gray's "Elegy" is hardly beyond the
browser's limit.

In an editorial on the Harvard Classics in the "Chicago evening post",
(April 22), we read, "the cultural tabloid has very little virtue;... to
gain everything that a book has to give one must be submerged in it,
saturated and absorbed". This is very much like saying, "there is very
little nourishment in a sandwich; to get the full effect of a luncheon you
must eat everything on the table". It is a truism to say that you can not
get everything in a book without reading all of it; but it by no means
follows that the virtue of less than the whole is negligible.

So much for the direct effect of what one may thus take in, bit by bit.
The indirect effect is even more important. For by sampling a whole
literature, as he does, he not only gets a bird's-eye view of it, but he
finds out what lie likes and what he dislikes; he begins to form his
taste. Are you afraid that he will form it wrong? I am not. We are
assuming that the library where he browses is a good one; here is no
chance of evil, only a choice between different kinds of good. And even if
the evil be there, it is astonishing how the healthy mind will let it slip
and fasten eagerly on the good. Would you prefer a taste fixed by someone
who tells the browser what he ought to like? Then that is not the reader's
own taste at all, but that of his informant. We have too much of this sort
of thing--too many readers without an atom of taste of their own who will
say, for instance, that they adore George Meredith, because some one has
told them that all intellectual persons do so. The man who frankly loves
George Ade and can yet see nothing in Shakespeare may one day discover
Shakespeare. The man who reads Shakespeare merely because he thinks he
ought to is hopeless.

But what a triumph, to stand spell-bound by the art of a writer whose name
you never heard, and then discover that he is one of the great ones of the
world! Nought is comparable to it except perhaps to pick out all by
yourself in the exhibition the one picture that the experts have chosen
for the museum or to be able to say you liked olives the first time you
tasted them.

Who are your favorites? Did some one guide you to them or did you find
them yourselves? I will warrant that in many cases you discovered them and
that this is why you love them. I discovered DeQuincey's romances, Praed's
poetry, Béranger in French, Heine in German, "The Arabian nights",
Molière, Irving's "Alhambra," hundreds of others probably. I am sure that
I love them all far more than if some one had told me they were good
books. If I had been obliged to read them in school and pass an
examination on them, I should have hated them. The teacher who can write
an examination paper on Gray's "Elegy", would, I firmly believe, cut up
his grandmother alive before the physiology class.

And next to the author or the book that you have discovered yourself comes
the one that the discoverer himself--your boy or girl friend--tells you
about. _He_ knows a good thing--_she_ knows it! No school nonsense about
that; no adult misunderstanding. I found out Poe that way, and Thackeray's
"Major Gahagan", and many others.

To go back to our old illustration and consider for a moment not the book
but the mind, the personality whose ideas it records, such association
with books represents association with one's fellowmen in society--at a
reception, in school or college, at a club. Some we pass by with a nod,
with some we exchange a word; sometimes there is a warm handgrasp;
sometimes a long conversation. No matter what the mental contact may be,
it has its effects--we are continually gaining knowledge, making new
friends, receiving fresh inspiration. The complexion of this kind of daily
association determines the cast of one's mind, the thoroughness of his
taste, the usefulness or uselessness of what he does. A man is known by
the company he keeps, because that company forms him; he gets from it what
becomes brain of his brain and soul of his soul.

And no less is he formed by his mental associations with the good and the
great of all ages whom he meets in books and who talk to him there. More
rather than less; for into a book the writer puts generally what is best
in him, laying aside the pettiness, the triviality, the downright
wickedness that may have characterized him in the flesh.

I have often heard the comment from one who had met face to face a writer
whose work he loved--"Oh! he disappointed me so!" How disappointed might
we be with Thackeray, with Dickens, even with Shakespeare, could we meet
them in the flesh! Now they can not disappoint us, for we know only what
they have left on record--the best, the most enduring part, purified from
what is gross and earthly.

In and among such company as this it is your privilege to live and move,
almost without money and without price. Thank God for books; let them be
your friends and companions through life--for information, for recreation,
but above all for inspiration.




ATOMIC THEORIES OF ENERGY[6]

[6] Read before the St. Louis Academy of Science.


A theory involving some sort of a discrete or discontinuous structure of
energy has been put forward by Prof. Max Planck of the University of
Berlin. The various aspects of this theory are discussed and elaborated by
the late M. Henri Poincaré in a paper entitled "L'Hypothèse des Quanta,"
published in the _Revue Scientifique_ (Paris, Feb. 21, 1912).

A paper in which a discontinuous or "atomic" structure of energy was
suggested was prepared by the present writer fifteen years ago but remains
unpublished for reasons that will appear later. Although he has no desire
to put in a claim of priority and is well aware that failure to publish
would put any such claim out of court, it seems to him that in connection
with present radical developments in physical theory the paper, together
with some correspondence relating thereto, has historical interest.
Planck's theory was suggested by thermodynamical considerations. In the
paper now to be quoted the matter was approached from the standpoint of a
criterion for determining the identity of two portions of matter or of
energy. The paper is as follows:


_Some Consideration on the Identity of Definite Portions of Energy_

It has been remarked recently that physicists are now divided into two
opposing schools according to the way in which they view the subject of
energy, some regarding it as a mere mathematical abstraction and others
looking upon it as a physical entity, filling space and continuously
migrating by definite paths from one place to another. It may be added
that there are numerous factions within these two parties; for instance,
not all of those who consider energy to be something more than a mere
mathematical expression would maintain that a given quantity of it retains
its identity just as a given quantity of matter does. In fact a close
analysis would possibly show that opinions are graded very closely and
continuously from a view hardly differing from that of Lagrange, who
clearly saw and freely used the mathematical considerations involving
energy before the word had been invented or its physical meaning
developed, up to that stated recently in its extreme form by Professor
Ostwald, who would replace what he terms a mechanical theory of the
universe by an "energetical" theory, and would dwell exclusively on energy
as opposed to its vehicles.

Differences of opinion of this sort very frequently reduce to differences
of definition, and in this case the meaning of the word "identity" or some
similar word or phrase has undoubtedly much to do with the view that is
taken of the matter. It may be interesting, for instance, to look for a
moment at our ideas of the identity of matter and the extent to which they
are influenced by the accepted theory of its constitution.

Very few persons would hesitate to admit that the matter that now
constitutes the universe is identical in amount with that which
constituted it one million years ago, and that any given portion of that
matter is identical with an equal amount of matter that then existed,
although the situations of the parts of that portion might be and probably
were widely different in the two classes. To assert this is of course a
very different thing from asserting that the identity of the two portions
or any parts thereof could have been practically shown by following them
during all their changes of location or state. That cannot be done even in
the case of some simple changes that are effected in a fraction of a
second. For instance, if water from the pail A be mixed with water from
the pail B there is no possible way of telling which pail any given
portion of the mixture came from or in what proportions, yet it is certain
that such portion is identical with a portion of equal mass that recently
occupied part of one or both pails.

How far our certainty as to this is influenced by our ideas regarding the
ultimate constitution of the water is worthy of investigation. All who
accept the molecular theory, for instance, will regard our inability to
trace the elements of a mixture as due to purely physical limitations. A
set of Maxwell's "demons" if bidden to watch the molecules of the water in
pail A, one demon being assigned to each molecule, would be able to tell
us at any time the precise proportions of any given part of the mixture.
But if we should not accept the molecular theory and believe for instance,
that water is a continuum, absolutely homogeneous, no matter how small
portions of it be selected, then our demons would be as powerless as we
ourselves now are to trace the constituents in the mixture.

We are now in a position to ask the question: Is the matter in a mixture
of two continua identical with that of its constituents? The identity
certainly seems of a different kind or degree from that which obtains in
the first case, for there is no part, however small, that was derived from
one pail alone. The mixture is something more than a mere juxtaposition of
elements each of which has retained its identity; it is now of suck nature
that no part of it is identical with any part of A alone or of B alone,
nor of A+B, where the sign + denotes simple juxtaposition. It is
identical, to be sure, with a perfect mixture of certain parts of A and B,
but this is simply saying that it is identical with what it is now, that
is, with itself, not with something that went before.

Probably no one now believes that water or any other kind of matter is a
continuum, but the bearing of what has been said may be seen when we
remember that this is precisely the present stage of our belief regarding
energy.

No one, so far as I know, has ventured to suggest what may be termed a
molecular theory of energy, a somewhat remarkable fact when we consider
the control now exercised over all thought in physics by molecular
theories of matter. While we now believe, for instance, that a material
body, say a crystal, can by no possibility increase continuously in mass,
but must do so step by step, the minimum mass of matter that can be added
being the molecule, we believe on the contrary that the energy possessed
by the same body can and may increase with absolutely perfect continuity,
being hampered by no such restriction.

It is not the purpose of this paper to discuss whether we have grounds for
belief that there is such a thing as a minimum quantity, or atom, of
energy, that does not separate into smaller parts, no matter what changes
it undergoes. Suffice it to say that there appears to be no _a priori_
absurdity in such an idea. At first sight both matter and energy appear
non-molecular in structure. But we have been forced to look upon the
gradual growth of a crystal as a step-by-step process, and we may some
day, by equally cogent considerations, be forced to regard the gradual
increase of energy of an accelerating body as also a step-by-step process,
although the discontinuity is as invisible to the eye in the latter case
as in the former.

Without following this out any farther, however, the point may be here
emphasized that it is hardly possible for one who, like the majority of
physicists, regards matter as molecular and energy as a continuum, to hold
the same ideas regarding the identity of the two. Efforts to show that
definite portions of energy, like definite portions of matter, retain
their identity have hitherto been made chiefly on the lines of a
demonstration that energy travels by definite and continuous paths in
space just as matter does. This is very well, but it would appear to be
necessary to supplement it with evidence to show that the lines
representing these paths do not form at their intersections continuous
blurs that not only forbid any practical attempt at identification on
emergence, but make it doubtful whether we can in any true sense call the
issuing path identical with the entering one. Otherwise the identity of
energy can be admitted to be only that kind of identity that could be
preserved by matter if its molecular structure did not exist. One who can
admit that this sort of identity is the same sort that can be preserved by
molecular matter may be able to hold the identity of energy in the present
state of the evidence, but the present attitude of physicists would seem
to show that, whether they realize the connection of the two subjects or
not, they cannot take this view. In other words, modern views of the
identity of matter seem closely connected with modern views of its
structure, and the same connection will doubtless hold good for energy.

Regarding the probable success of an attempt to prove that energy has a
"structure" analogous to the molecular structure of matter, any prediction
would doubtless be rash just now. The writer has been unable, up to the
present time, to disprove the proposition, but the subject is one of
corresponding importance to that of the whole molecular theory of matter
and should not be entered upon lightly.

*       *       *       *       *

The writer freely acknowledges at present that the illustrations in the
foregoing are badly chosen and some of the statements are too strong, but
it still represents essentially his ideas on the subject. No reputable
scientific journal would undertake to publish it. The paper was then sent
to Prof. J. Willard Gibbs of Yale, and elicited the following letter from
him:

"NEW HAVEN, JUNE 2, 1897.

"MY DEAR MR. BOSTWICK:

"I regret that I have allowed your letter to lie so long
unanswered. It was in fact not very easy to answer, and when one
lays a letter aside to answer, the weeks slip away very fast.

"I do not think that you state the matter quite right in regard to
the mixture of fluids if they were continuous. The mixing of water
as I regard it would be like this, if it were continuous and not
molecular. Suppose you should take strips of white and red glass
and heat them until soft and twist them together. Keep on drawing
them out and doubling them up and twisting them together. It would
soon require a microscope to distinguish the red and white glass,
which would be drawn out into thinner and thinner filaments if the
matter were continuous. But it would be always only a matter of
optical power to distinguish perfectly the portion of red and
white glass. The stirring up of water from two pails would not
really mix them but only entangle filaments from the pails.

"To come to the case of energy. All our ideas concerning energy
seem to require that it is capable of gradual increase. Thus the
energy due to velocity can increase continuously if velocity can.
Since the energy is as the square of the velocity, if the velocity
can only increase discontinuously by equal increments, the energy
of the body will increase by unequal increments in such a way as
to make the exchange of energy between bodies a very awkward
matter to adjust.

"But apart from the question of the increase of energy by
discontinuous increments, the question of relative and absolute
motion makes it very hard to give a particular position to energy,
since the 'energy' we speak of in any case is not one quantity but
may be interpreted in a great many ways. Take the important case
of two equal elastic balls. One, moving, strikes the other at
rest, we say, and gives it nearly all its energy. But we have no
right to call one ball at rest and we can not say (as anything
absolute) which of the balls has lost and which has gained energy.
If there is such a thing as absolute energy of motion it is
something entirely unknowable to us. Take the solar system,
supposed isolated. We may take as our origin of coordinates the
center of gravity of the system. Or we may take an origin with
respect to which the center of gravity of the solar system has any
(constant) velocity. The kinetic energy of the earth, for example,
may have any value whatever, and the principle of the conservation
of energy will hold in any case for the whole solar system. But
the shifting of energy from one planet to another will take place
entirely differently when we estimate the energies with reference
to different origins.

"It does not seem to me that your ideas fit in with what we know
about nature. If you ask my advice, I should not advise you to try
to publish them.

"At best you would be entering into a discussion (perhaps not in
bad company) in which words would play a greater part than precise
ideas.

"This is the way I feel about it.

"I remain,
"Yours faithfully,
"J.W. GIBBS."

Professor Gibbs's criticism of the illustration of water-mixture is
evidently just. Another might well have been used where the things mixed
are not material--for instance, the value of money deposited in a bank. If
A and B each deposits $100 to C's credit and C then draws $10, there is
evidently no way of determining what part of it came from A and what from
B. The structure of "value", in other words, is perfectly continuous.
Professor Gibbs's objections to an "atomic" theory of the structure of
energy are most interesting. The difficulties that it involves are not
overstated. In 1897 they made it unnecessary, but since that time
considerations have been brought forward, and generally recognized, which
may make it necessary to brave those difficulties.

Planck's theory was suggested by the apparent necessity of modifying the
generally accepted theory of statistical equilibrium involving the so
called "law of equipartition," enunciated first for gases and extended to
liquids and solids.

In the first place the kinetic theory fixes the number of degrees of
freedom of each gaseous molecule, which would be three for argon, for
instance, and five for oxygen. But what prevents either from having the
six degrees to which ordinary mechanical theory entitles it? Furthermore,
the oxygen spectrum has more than five lines, and the molecule must
therefore vibrate in more than five modes. "Why," asks Poincaré, "do
certain degrees of freedom appear to play no part here; why are they, so
to speak, 'ankylosed'?" Again, suppose a system in statistical
equilibrium, each part gaining on an average, in a short time, exactly as
much as it loses. If the system consists of molecules and ether, as the
former have a finite number of degrees of freedom and the latter an
infinite number, the unmodified law of equipartition would require that
the ether should finally appropriate all energy, leaving none of it to the
matter. To escape this conclusion we have Rayleigh's law that the radiated
energy, for a given wave length, is proportional to the absolute
temperature, and for a given temperature is in inverse ratio to the fourth
power of the wave-length. This is found by Planck to be experimentally
unverifiable, the radiation being less for small wave-lengths and low
temperatures, than the law requires.

Still again, the specific heats of solids, instead of being sensibly
constant at all temperatures, are found to diminish rapidly in the low
temperatures now available in liquid air or hydrogen and apparently tend
to disappear at absolute zero. "All takes place," says Poincaré, "as if
these molecules lost some of their degrees of freedom in cooling--as if
some of their articulations froze at the limit."

Planck attempts to explain these facts by introducing the idea of what he
calls "quanta" of energy. To quote from Poincaré's paper:

"How should we picture a radiating body? We know that a Hertz resonator
sends into the ether Hertzian waves that are identical with luminous
waves; an incandescent body must then be regarded as containing a very
great number of tiny resonators. When the body is heated, these resonators
acquire energy, start vibrating and consequently radiate.

"Planck's hypothesis consists in the supposition that each of these
resonators can acquire or lose energy only by abrupt jumps, in such a way
that the store of energy that it possesses must always be a multiple of a
constant quantity, which he calls a 'quantum'--must be composed of a whole
number of quanta. This indivisible unit, this quantum, is not the same for
all resonators; it is in inverse ratio to the wave-length, so that
resonators of short period can take in energy only in large pieces, while
those of long period can absorb or give it out by small bits. What is the
result? Great effort is necessary to agitate a short-period resonator,
since this requires at least a quantity of energy equal to its quantum,
which is great. The chances are, then, that these resonators will keep
quiet, especially if the temperature is low, and it is for this reason
that there is relatively little short-wave radiation in 'black
radiation'... The diminution of specific-heats is explained similarly:
When the temperature falls, a large number of vibrators fall below their
quantum and cease to vibrate, so that the total energy diminishes faster
than the old theories require."

Here we have the germs of an atomic theory of energy. As Poincaré now
points out, the trouble is that the quanta are not constant. In his study
of the matter he notes that the work of Prof. Wilhelm Wien, of Würzburg,
leads by theory to precisely the conclusion announced by Planck that if we
are to hold to the accepted ideas of statistical equilibrium the energy
can vary only by quanta inversely proportional to wave-length. The
mechanical property of the resonators imagined by Planck is therefore
precisely that which Wien's theory requires. If we are to suppose atoms of
energy, therefore, they must be variable atoms. There are other objections
which need not be touched upon here, the whole theory being in a very
early stage. To quote Poincaré again:

"The new conception is seductive from a certain standpoint: for some time
the tendency has been toward atomism. Matter appears to us as formed of
indivisible atoms; electricity is no longer continuous, not infinitely
divisible. It resolves itself into equally-charged electrons; we have also
now the magneton, or atom of magnetism. From this point of view the quanta
appear as _atoms_ of _energy_. Unfortunately the comparison may not be
pushed to the limit; a hydrogen atom is really invariable.... The
electrons preserve their individuality amid the most diverse vicissitudes,
is it the same with the atoms of energy? We have, for instance, three
quanta of energy in a resonator whose wave-length is 3; this passes to a
second resonator whose wave-length is 5; it now represents not 3 but 5
quanta, since the quantum of the new resonator is smaller and in the
transformation the number of atoms and the size of each has changed."

If, however, we replace the atom of energy by an "atom of action," these
atoms may be considered equal and invariable. The whole study of
thermodynamic equilibrium has been reduced by the French mathematical
school to a question of probability. "The probability of a continuous
variable is obtained by considering elementary independent domains of
equal probability.... In the classic dynamics we use, to find these
elementary domains, the theorem that two physical states of which one is
the necessary effect of the other are equally probable. In a physical
system if we represent by _q_ one of the generalized coordinates and by
_p_ the corresponding momentum, according to Liouville's theorem the
domain [double integral]_dpdq_, considered at given instant, is invariable
with respect to the time if _p_ and _q_ vary according to Hamilton's
equations. On the other hand _p_ and _q_ may, at a given instant take all
possible values, independent of each other. Whence it follows that the
elementary domain is infinitely small, of the magnitude _dpdq_.... The new
hypothesis has for its object to restrict the variability of _p_ and _q_
so that these variables will only change by jumps.... Thus the number of
elementary domains of probability is reduced and the extent of each is
augmented. The hypothesis of quanta of action consists in supposing that
these domains are all equal and no longer infinitely small but finite and
that for each [double integral]_dpdq_ equals _h_, _h_ being a constant."

Put a little less mathematically, this simply means that as energy equals
action multiplied by frequency, the fact that the quantum of energy is
proportional to the frequency (or inversely to the wave-length as stated
above) is due simply to the fact that the quantum of action is constant--a
real atom. The general effect on our physical conceptions, however, is the
same: we have a purely discontinuous universe--discontinuous not only in
matter but in energy and the flow of time. M. Poincaré thus puts it: "A
physical system is susceptible only of a finite number of distinct states;
it leaps from one of these to the next without passing through any
continuous series of intermediate states."

He notes later:

"The universe, then, leaps suddenly from one state to another; but in the
interval it must remain immovable, and the divers instants during which it
keeps in the same state can no longer be discriminated from one another;
we thus reach a conception of the discontinuous variation of time--the
atom of _time_."

I quote in conclusion, Poincaré's final remarks:

"The present state of the question is thus as follows: the old theories,
which hitherto seemed to account for all the known phenomena, have met
with an unexpected obstacle. Seemingly a modification becomes necessary. A
hypothesis has presented itself to M. Planck's mind, but so strange a one
that one is tempted to seek every means of escaping it; these means,
however, have been sought vainly. The new theory, however, raises a host
of difficulties, many of which are real and not simply illusions due to
the indolence of our minds, unwilling to change their modes of thought....

"Is discontinuity to reign through out the physical universe, and is its
triumph definitive? Or rather shall we find that it is but apparent and
hides a series of continuous processes?... To try to give an opinion just
now on these questions would only be to waste ink."

It only remains to call attention again to the fact that this conception
of the discontinuity of energy, the acceptance of which Poincaré says
would be "the most profound revolution that natural philosophy has
undergone since Newton" was suggested by the present writer fifteen years
ago. Its reception and serious consideration by one of the first
mathematical physicists of the world seems a sufficient justification of
its suggestion then as a legitimate scientific hypothesis.




THE ADVERTISEMENT OF IDEAS


Writing is a device for the storage of ideas--the only device for this
purpose prior to the invention of the phonograph, and not now likely to be
generally superseded. A book consists of stored ideas; sometimes it is
like a box, from which the contents must be lifted slowly and with more or
less toil; sometimes like a storage battery where one only has to make the
right kind of contact to get a discharge. At any rate, if we want people
to use books or to use them more, or to use them better, or to use a
different kind from that which they now use, we must lose sight for a
moment of the material part of the book, which is only the box or the lead
and acid of the storage battery, and fix our attention on the stored
ideas, which are what everybody wants--everybody, that is, except those
who collect books as curiosities. The subject of this lecture is thus only
library advertising, about which we have heard a good deal of late, but we
shall try to confine its applications to this inner or ideal substance
which it is our special business as librarians to purvey. And first, in
considering the matter, it may be worth while to say a word about
advertising in general. Practically an advertisement is an announcement by
somebody who has something to distribute. Announcements of this kind may
be classified, it seems to me, as economic, uneconomic and illegitimate.

The most elementary form is that of the person who tells you where you can
get something that you want--a simple statement that someone is a barber
or an inn-keeper, or gives music lessons, or has shoes for sale. This may
be accompanied by an effort to show that the goods offered are of
specially good quality or have some feature that makes them particularly
desirable, either to consumers in general or to those of a certain class.
This is all surely economic, so long as nothing but the truth is told.
Next we have an effort not only to supply existing wants and to direct
them into some particular channel, but to create a new field, to make
people realize a lack previously not felt; in other words to make people
want something that they need. This may be done simply by exhibiting or
describing the article or it may require long and skillful presentation of
the matter. All this is still economic. But it requires only a step to
carry us across the line. Next the enthusiastic advertiser strives to make
someone want that which he does not need. As may be seen, the line here is
difficult to determine, but this sort of advertising is surely not
economic. So long as the thing not needed is not really injurious,
however, the advertising cannot be called illegitimate. It is simply
uneconomic. The world would be better off without it, but we may look for
its abolition only to the increase of good judgment and intelligence among
consumers. When an attempt however, is made to cause a man to want
something that is really injurious, then the act becomes illegitimate and
should be prevented. Another class of illegitimate advertising is that
which would be perfectly allowable if it were truthful and becomes
objectionable only because its representations are false. It may be
ostensibly of any of the types noted above.

As we have already noted, the material objects distributed by the
librarian are valued not for their physical characteristics but for a
different reason altogether, the fact that they contain stored ideas.
Ideas which, according to some, are merely the relative positions of
material particles in the brain, and which are indisputably accompanied
and conditioned by such positions, here subsist in the form of peculiar
and visible arrangements of particles of printer's ink upon paper, which
are capable under certain conditions of generating in the human brain
ideas precisely similar to those that gave them birth. And although the
book cannot think for itself, but must merely preserve the idea intrusted
to it, without change, it is vastly superior in stability to the brain
that gave it birth, so that thousands of years after that brain has
mouldered into dust it is capable of reproducing the original ideas in a
second brain where they may germinate and bear fruit. How familiar all
this is, and yet how perennially wonderful! The miracle of it is
sufficient excuse for this digression.

Now books, beside this modern form of distribution by loan, are widely
distributed commercially both by loan and by sale, and especially in the
latter form advertisement is now very extensively used in connection with
the distribution. In fact we have all the different types specified
above--economic, uneconomic and illegitimate, both through
misrepresentation and the harmful character of the subject matter. The
reason for all illegitimate forms of advertising is of course not a desire
to misrepresent or to do harm per se, but to make money, the profit to the
distributor being proportioned to the amount of distribution done and not
at all dependent on its economic value. Distribution by public officers is
of course not open to this objection, nor are the distributors subject to
temptation, since their compensation does not depend on the amount of
distribution. If they are capable and interested, furthermore, they are
particularly desirous to increase the economic value of the work that they
are doing. Since this is so and since the danger of uneconomic or harmful
forms of advertising is thus reduced to a minimum, there would seem to be
special reason why the economic forms should be employed very freely. But
the fact is that they have been used sparingly, and by some librarians
shunned altogether.

Let us see what library advertising of the economic types may mean. In the
first place it means telling those who want books where they may get them.
This simple task is rarely performed completely or satisfactorily. It is
astonishing how many inhabitants of a large town do not even know where
the public library is. Everyone realizes this who has ever tried to find a
public library in a strange place. I once asked repeatedly of passers-by
in a crowded city street a block distant from a library (in this case not
architecturally conspicuous) before finding one who knew its whereabouts;
in another city I inquired in vain of a conductor who passed the building
every few hours in his car. In the latter case the library was a beautiful
structure calculated to move the curiosity of a less stolid citizen. In
New York inquiry would probably cause you to reach the nearest branch
library, anything more remote than that being beyond the local
intelligence. Sometimes I think we had better drop all our far-reaching
plans for civic betterment and devote our time for a few years to causing
citizens, lettered and unlettered alike to memorize some such simple
formula as this: "There is a Public Library. It is on Blank street. We may
borrow books there, free."

You will notice that I have inserted in this formula one item of
information that pertains to use, not location. For of those who know of
the existence and location of the Public Library there are many whose
ideas of its contents and their uses, and of the conditions and value of
such uses, are limited and crude. The advertising that succeeds in
bettering this state of things is surely doing an economic service. All
these things the self-respecting citizen should know. But beyond and above
all this there is the final economic service of advertising--the causing a
man to want that which he needs but does not yet desire. Every man, woman
and child in every town and village needs books in some shape, degree,
form or substance. And yet the proportion of those who desire them is yet
outrageously small, though encouragingly on the increase. Here no
memorizing of a formula, even could we compass it, could suffice. This
kind of advertising means the realization of something lacking in a life.
Is the awakening of such a realization too much for us? Are we to stand by
and see our neighbors all about us awakening to the undoubted fact that
they need telephones in their houses, and electric runabouts, and
mechanical fans in hot weather, and pianolas, and new kinds of breakfast
food, while we despair of awakening them to their needs of books--quite as
undoubted? Are we to admit that personal gain, which was the victorious
motive that spurred on the commercial advertisers in these and countless
other instances, is to be counted more mighty than the desire to do a
service to our fellowmen and to fulfill the duties of our positions--which
should spur us on?

I am not foolish enough to suppose that by placarding the fences with the
words "Books! Books!" as the patent medicine man does with "Curoline!
Curoline!" we shall make any progress. The patent medicine man is right;
he wants to excite curiosity and familiarize the public with the name of
his nostrum. They all know what a book is--and alas the name is not even
unknown and mysterious--would that it were! It calls up in many minds
associations which, if we are to be successful we must combat, overthrow,
and replace by others. To many--sad it is to say it--a book is an
abhorrent thing; to more still, it is a thing of absolute indifference. To
some a book is merely a collection of things, having no ascertainable
relationships, that one is required to memorize; to others it is a
collection of statements, difficult to understand, out of which the
meaning must be extracted by hard study; to very few indeed does the book
appear to be what it really is--a message from another mind. People will
go to a seance and listen with thrills to the silliest stuff purporting to
proceed from Plato or Daniel Webster or Abraham Lincoln, when in the
Public Library, a few blocks away are important and authentic messages
from those same persons, to which they have never given heed. Such a
message derives interest and significance from circumstances outside
itself. Very few books create their own atmosphere unaided. They
presuppose a system of abilities, opinions, prejudices, likes and
dislikes, intellectual connections and what not, that is little less than
appalling, if we try to follow it up. Dislike of books or indifference
toward them is often simply the result of a lack of these things or of
some component part of them. We must supply what is lacking if we are to
arouse a desire for books in those who do not yet possess it. I say that
such a labor is difficult enough to interest him whose pleasure it is to