THE MARCH OF SCIENCE
In a forecast like the present it is impossible to avoid a certain
amount of overlapping in different sections of the subject and
a certain blending of topics in a single chapter. The attempt to
differentiate consistently between the progress of science as science,
and the concurrent advance of practical invention by which scientific
discovery is turned to use would only involve needless repetition. I
have already had occasion to suggest elements of material progress
which presuppose the advance in pure science that would make them
possible. Thus, in endeavouring to suggest what the methods of commerce
and the condition of our cities are likely to be in the future it
was necessary to conceive certain advances in our knowledge of what
is rather clumsily called "wireless" telegraphy, and to predict
the discovery of new and cheap methods of analysing water into its
component gases as a source of fuel and as means for the production
of electricity: and in order to avoid useless repetition it was found
convenient to work out in a rough manner the various ways in which the
cheap and inexhaustible supplies of hydrogen and oxygen which I have
imagined discovery to have placed at the disposal of invention would
be employed in the arts. Similarly, when we interrogate imagination
on the subject of scientific discovery itself, we shall be forced to
think chiefly of the practical results likely to be achieved by it,
and indeed there would otherwise be hardly any purpose to serve by
the effort. What imports the greatest amount of complexity into the
subject is the difficulty of conceiving the lines upon which science
is likely to travel, unless we allow ourselves to be guided by the
practical requirements of the future as far as we are able to foresee
them. Imagination has indeed superabundant room in which to run riot
when it endeavours to give form to the probabilities of scientific
discovery; and the only danger is that effort may be wasted in purely
fanciful directions, if it be not pretty securely tied down by some
such artificial restraint as the convention of keeping more or less
strictly to the anticipation of discoveries likely to have immediate
practical application.
For instance, there is hardly any end to the developments we might
allow ourselves to imagine as arising out of the new theories, still in
a probationary condition, as to the ultimate physical structure of the
universe. Such conjectures might be followed indefinitely in several
directions, and the resulting conclusions would be more likely to
err by timidity than by extravagance: but as there is no knowledge at
present available which could serve as a guide to the probably-right,
and as a warning against the probably-wrong, directions, it would be
neither interesting nor useful to pursue them. Radium "the revealer,"
as Dr Saleeby has called it in one of those brilliant papers which
fine imagination and delicate fancy have adorned with many another
noble phrase and memorable image, opens the door to a whole world of
new possibilities. Our whole conception of cosmic processes may have
to be remodelled, in the light of those tiny scintillations which the
spinthariscope has popularised. Already our notions concerning the
nature of matter have been revolutionised. We are told that atoms,
regarded hitherto as the ultimate units of matter--so small that Lord
Kelvin has calculated that if a drop of water were magnified to the
size of the earth the atoms in it would be somewhere between the size
of small shot and the size of cricket balls--are themselves made up
of a stuff so almost infinitely more tenuous, that the particles of
it within the atom are, relatively to their size, farther apart than
the planets of the solar system. Nor is this all. These particles,
commonly called electrons, if particles they can still be designated at
all, were at first said to "carry" a charge of electricity. But it now
seems that they are electricity itself. If this be true, we should seem
to be on the point of bridging the void between what used to be called
the eternal antithetics--matter and force: and whither this will lead
us can only with the greatest caution be pre-imagined. In any case the
consequences of this discovery, philosophical as well as scientific,
are stupefying in the possibilities they open up to the thinker as
well as to the man of practical science. At last science begins to join
hands with philosophy. What will be the philosophy of a hundred years
hence, imagination pales before the effort of attempting to conceive.
But the working out of the revelations promised by radiology belongs
rather to this end of the century than to the other. During the
interval there can be no doubt that electricity, already man's chief
handmaid, will have increased and perhaps completed her services
to the race. When, as I ventured to suggest in a former chapter,
inexhaustible and cheap "current" is yielded to us by some method
of utilising the electrical reciprocity of the hydrogen and oxygen
gases derived from water, doubtless all machinery will be electrically
driven, all transport electrically propelled. Perhaps this discovery
lies so far in the foreground of the future as to be irrelevant to any
anticipations of the world's condition a hundred years hence. The
full development of electrically-driven machinery lies in the
middle distance, and the duration of the electrical age can hardly
be precalculated with any greater exactness than the suggestion that
it will probably have reached, or at all events approached, its end
in about a century's time.
The most important problem connected with this subject is to
imagine, if we can, how electrical power will be applied. It is quite
evident that the device of long conductors, either overhead or below
ground--the "live wires" of alarmed America--is too clumsy and too
dangerous to be long tolerated. It is indeed a public scandal that
cables carrying an electrical charge capable of killing or paralysing
at a touch should be suspended over the heads of the citizens, exposed
to momentary breakage by snowfall, high wind, or the inevitable
wear which careless inspectors may overlook: and the mere fact that
a horse can occasionally set foot on a ground plate and fall dead
from the contact shows that even the vaunted "conduit system" must
not be regarded as anything but a strictly-temporary device. Some of
the dangers of the underground electric wires arise out of the use
of our present illuminating gas, when a pipe leaks into a manhole
or inspection chamber, forming an explosive mixture of gas and air,
which presently becomes ignited by an electric spark and blows up the
whole affair. No doubt coal gas is within easily measurable distance
of its end as a convenience of civilisation. But it is extremely
probable that hydrogen and oxygen will be conveyed by mains to houses
and public buildings during a long time: and it is hardly possible
to believe that the mains will not sometimes leak and be capable of
letting out mixtures far more dangerous on ignition than the mixture
of coal gas and air, and still more dangerous because neither of the
gases, nor the mixture of them, has any smell, unless indeed we should
take the precaution of giving them one artificially. Whatever we may
do, and we shall do much, to minimise the dangers of highly-evolved
civilisation, accidents will always occur, and their violence will
probably increase. We must pay our toll to the conveniences of life,
and we shall of course compensate ourselves by a lower death-rate
from diseases, many of which will no doubt in a hundred years' time
have disappeared from the planet.
If we need any motive power other than electricity, or if we need
motive power of some other kind to produce electricity, no doubt
the explosive recombination of oxygen and hydrogen, controlled by
devices developed from existing gas-engines and petrol-engines, will
be a starting-point: because coal will, probably before the complete
exhaustion of the supply of it, have been found altogether too dirty
and unhealthy a thing to use, at all events by way of combustion,
though rumours are heard from time to time of new methods by which
the stored energy of coal may be utilised directly, to the great
economy of the material. [13] In all sorts of ways the early years of
the century will be employing themselves in seeking out new sources
of man's chief necessity--power: and a hundred years hence we shall
have entered upon the full inheritance of them.
But the obtaining of power is only one problem of the mechanician. Of
almost equal, if not quite equal, importance is that of applying power
at the place where it is needed, and the careful reader will not have
overlooked the fact that while we have been discussing the use of
electricity as a source of power we have already been anticipating,
and perhaps anticipating a good deal. For, when we now speak of
machinery and locomotive engines being "driven" by electricity, we
are really only employing a sort of convenient periphrasis. All our
electric machinery, all our electric railways, our "tuppeny" tubes
and the horrible electric trams which make life almost intolerable in
houses along many of the main roads out of London, are really driven by
coal-burning steam engines. In a few places (especially in the Niagara
valley) waterfall power is used. But whatever the real source of power,
electricity is only a means, more or less convenient, of transmitting
it. Even electric launches, and slow-going electric broughams driven
by accumulators, only represent slightly more subtle examples of the
electrical transmission of power. The ultimate source of power is
always either a steam-engine or a waterfall. A few lecture-table toys
and the like are the only existing examples of machinery in which the
actual source of power is electricity. Even here, it may be objected,
the actual source of power is not electricity, but chemical action
in the battery. But no contrivance of man is an ultimate source of
power. Even a steam-engine is only a device for utilising the stored
solar energy of coal. Of course man can no more create power than
he can create matter: the stock of each in the universe is a fixed
quantity. All that we are able to do is to harness to our use a part
of the cosmic store. When I speak of electricity becoming hereafter
a "source" of power, I am merely distinguishing between its use as
a means of transmitting force already perceived as force in some
other form (as where a dynamo-electric machine receives motion from
a steam-engine or waterfall and turns this motion into electricity,
which is conveyed by wires or rails to an electric dynamic engine
that reconverts it into motion) and its use as a primary means of
utilising the cosmic stores of force.
Before we arrive, therefore, at the point of using electricity as
a source of power in itself, our mechanicians will have plenty to
occupy them in the task of devising safer and more convenient methods
of transmitting force, and even at the end of the century, supposing
the use of electricity not to have been entirely superseded by the
discovery of some entirely new force as yet not even conceivable,
invention will doubtless be still busy with further improvements in
the transmission as well as in the production of electricity. It has
been hinted that "wireless" transmission of power will no doubt by
that time have become practicable, and Signor Marconi's achievement
of wireless telegraphy was mentioned as a proof that such transmission
is at least imaginable. In Marconi's invention an enormous electrical
impulse is launched into the æther, and if the very smallest token
of it can be "picked up" in any way at the receiving station, the
wireless telegram is satisfactorily received. But the important fact
for our present purpose is that some product of the original impulse
can be picked up: and though the effort of imagination required to
see in this a starting-point for entirely new inventions, capable
of gathering up a practicable modicum of the transmitted power in
a form capable of being converted into motion, is severe, we shall
bring but a poor imaginative equipment to a task so colossal as that
of guessing what the next century will be capable of if we refuse to
believe that something in the nature of Hertzian waves, or something
propagated as these are propagated, can be used to carry impulse to
machinery at a distance from the source of power. The imaginative
faculty which boggles at this effort will probably overlook the fact
that the mere transmission is only a part of the difficulty which
is pretty sure to have been overcome by this time next century. It
will not be enough to launch waves capable of being used where they
are intended to be used. We must also discover how to launch them
so that they may be incapable of being used anywhere else. I read
the other day the report of a police-court case in which a man was
charged with "stealing electricity" (which seems a rather doubtful
indictment from the point of view of the lawyer) by obtaining the
use of a public telephone station without paying the usual fee. The
electricians of a hundred years hence will certainly have to find
out how to prevent the purloining of wireless force, and perhaps the
police will have to devise means of detecting this at present somewhat
recondite crime. This question of wireless transmission lies within
the province of discovery rather than that of invention. Before it can
receive actuality we have to do more than utilise existing knowledge:
we have to acquire new knowledge.
In the meantime, portable energy will no doubt be achieved in ways
other than electrical. Some very interesting compressed-air tools are
already in limited use. Holes are drilled and rivets driven by little
contrivances which have a store of force within themselves furnished by
compressed air. One of the many uses of the cheap oxygen and hydrogen,
and doubtless of cheaply liquefied gases of high-resisting power, [14]
will no doubt be to work various kinds of machinery. This use of liquid
airs has been much derided, and indeed a good deal of nonsense has been
written as to its possibilities, drawing from a recent and accomplished
writer the remark that "The statements which have sometimes appeared
in the daily papers, announcing impending revolutions in the methods of
obtaining cheap power by the application of liquid air, have originated
from an imperfect comprehension of the problems involved." [15]
In present conditions, and so far as we are able to see at present,
liquefied gases are for a long time not likely to serve any greater
mechanical purpose than that of furnishing a highly portable apparatus
by which great power can be developed for a short time at any required
place. It is easy to believe that it could not be otherwise employed
with any economy, even when discovery has greatly simplified the now
difficult process of liquefaction. But in regard to this matter, and
to almost every other mechanical and engineering improvement suggested
in the present work, it is of the first importance to remember that
the conditions in which the work of the world a hundred years hence
will be done are certain to differ very greatly from anything we know
to-day; and that procedures at present not merely out of proportion,
but in themselves actually chimerical, will become perfectly workable
in the new circumstances of another century. No doubt the problems at
present involved make many of the developments herein suggested almost
laughable to those who examine the subject without imagination. But
what could have been thought of a man who, when Oersted discovered the
influence of a battery current on the compass needle, suggested that
the discovery might, in much less than a hundred years, be practically
developed in such unforeseen ways as to produce locomotive machines
capable of carrying vast weight at a speed of perhaps a hundred
miles an hour? He would have been told that such predictions "could
only have originated from an imperfect comprehension of the problems
involved." But we know that they would have been perfectly sound,
though it would have been difficult to withhold assent from the
derision which instructed hearers would have poured upon them. The
effect of any scientific discovery can only be measured when we are in
a position to judge of the conditions in which it may be applied, and
the further discoveries which may affect it--a consideration which will
help us against the danger of undue caution in estimating the possible
developments of recent discovery when utilised in the conditions of the
next century and reinforced by inventions and discoveries yet to come.
A like caution will, however, teach us to restrain our expectations
from the new knowledge which radium appears to be gradually unfolding,
not because there is any doubt that radio-activity will ultimately
bring priceless gifts to civilisation, but because in our present
ignorance of all but a few facts concerning it we can form no possible
conjecture as to the lines these gifts will follow. Already we seem
to have seen in some of the radium experiments one "element" turn into
another. If this should develop until we acquire the power which used
to be dreamed of as transmutation, the social and economic upheavals
which would result beggar imagination. [16]
The photographic effect of Röntgen rays has already [17] been
the subject of a suggestion, and even the facts now remotest from
practical use in connection with the rays of various sorts so much
discussed in the scientific newspapers will no doubt be utilised in
a manner or in manners far removed from the limited employment in
therapeutics already found for them.
And indeed medicine, not the most progressive of modern sciences,
will no doubt make vast strides during the period under discussion.
It would be altogether fallacious to forecast the position and
probable achievements of medical science in a century's time on the
line of simple development from the practice of to-day. The changes
will be revolutionary rather than evolutionary. When it is remembered
that only fifty years ago limbs were hacked from the quivering flesh
of the sentient patient, held down by muscular assistants lest the
violent struggles of his agony should embarrass the surgeon, and that
wounds of all sorts festered and decayed until a hospital reeked
with their impurity--in other words, that discoveries so great as
anæsthesia and antisepsis are well within living memory--we need not
hesitate to predict for the present century changes in medical and
surgical science almost inconceivable by the light of our present
attainment. Anæsthetics--of which the local kinds, as cocaine and
eucaine, are of entirely recent use--represent an advance in one
direction. Antiseptic surgery, which is the prevention and correction
of blood and wound-poisoning by chemical disinfectants, represented an
advance of a different kind. But antisepsis is already on the point
of being superseded by the far more rational and scientific method
of asepsis, or the exclusion from open wounds of all the germs which
can set up inflammation and festering. The change is typical.
The direction in which medicine is chiefly working at the present
time is that of introducing into the body one disease with the
idea of excluding other diseases. It is conceived that cow-pox
is antagonistic to small-pox, erysipelas possibly to cancer, and
so on. All the talk in medical circles is of serum and attenuated
virus. And, apart from animal products administered by injection, we
cure or attempt to cure all diseases by administering poisons--animal,
vegetable or mineral. Just as by antiseptics we poison the germ which
causes festering and inflammation, so by drugs we attempt to poison
disease--for all drugs are practically poisons. The principle of their
administration is almost wholly empirical. If you ask a doctor why
phenacetin reduces fever, it is impossible to get beyond a metaphysical
explanation. He will reply that phenacetin reduces fever by lowering
the blood pressure, or something of that kind. But this merely
re-states the problem. Why does phenacetin lower blood pressure? We
do not know. The substitution of asepsis for antisepsis--that is,
of cleanliness for disinfection--has hardly yet been perceived
to be in a certain sense the greatest advance in therapeutics
since Hippocrates. It probably contains the germ of future medical
treatment. Hereafter we shall not try to cast out devils of disease
by other disease-germs only less devilish. We shall learn enough of
the causes of disease to stop them at their source, and knowledge
growing from more to more, which has taught us exactly how "matter
in the wrong place"--of whatever sort--is the source of all disease,
will also show how matter may generally be kept in its right place.
Although comparatively little progress has been made by the curative
use of rays, other discoveries, of which we have even now passed the
brink, will have an enormous effect on medicine and surgery. Already
certain kinds of light cure rodent ulcer, one of the most hideous and
terrible diseases, not by the importation of fresh substances into the
body but by the modification of the tissues themselves. When radiation
has been fully studied it will almost certainly be found that the
sun, which is the source of practically all terrestrial activity,
has been showering upon us, ever since the homogeneous vapour which
was the birth-stuff of the universe aggregated itself into worlds and
suns and planets, rays which are capable of correcting every sort of
disease-germination and, properly used, of preventing it. The absolute
deadliness of unmodified sunlight to many sorts of disease-germs is
recognised already. The value of sun-baths--the exposure of the whole
body, undraped or only lightly covered, to the sunlight--is already
discussed in connection with anæmia, chlorosis and the early stages
of consumption. When we know just where all disease originates,
and why it develops, it seems likely that sunlight and oxygen its
child will prevent nearly all disease and cure whatever disease
accidentally arises. In place of temporary and dangerous expedients
like antiseptics, serum and corrective poisons, we shall import nothing
into the human organism, but only exclude what ought to be kept out,
and modify into innocuousness what has found its way in.
A great part of the disease we call constitutional, as distinguished
from infective, arises from food, either because the food itself is
not free from disease, or because, from excess in quantity or error
in choice, the food we take sets up the production of poisons in the
course of digestion, and by yielding, for instance, lactic or uric
acid to the blood causes rheumatism or gout, or by introducing into
the stomach matter in a state of incipient decay, favours typhoid
and other fevers.
When, for reasons already indicated, animal food has been eliminated
from the menu one great source of disease will have been got rid of.
When we completely understand the nature of the infective and
contagious diseases it seems well within the bounds of possibility
that the systematic destruction of their germs may be carried far
enough to remove them altogether from the planet. [18] We have now,
even by the highly imperfect measure of quarantine and a period
of muzzling (from which, on no evident ground except that it would
interfere with the amusements of the governing class to include them,
sporting dogs were excluded), apparently banished hydrophobia from
Great Britain. If it prove to be the case that just as hydrophobia
cannot arise spontaneously, but requires to be "started" by the entry
into the blood of an animal of an existing infection, other infective
diseases require pre-existing disease before they can arise, we may
get rid of them altogether. The dream may appear a wild one. But
it is not wilder than the dreams of a thinker who anticipated any
one of a hundred common facts of to-day must have appeared to our
great-great-grandfathers.
It is, of course, not to be supposed that disease can altogether be
banished from a world so highly artificial as that of the next century
will be. Undoubtedly the growth of sanitary science and the knowledge
of the larger facts of hygiene, which is only now beginning to dawn
upon us, will have a great influence in correcting some of the evils
which over-civilisation at present entails. But the very progress of
the art of healing will no doubt have the effect of perpetuating in a
manner the existence of illness. Every forward step in medicine serves
to save alive some weakling that in a less advanced civilisation would
die; and these survivors, possibly propagating their species, will have
weak descendants, on whom whatever possibility of disease continues
to exist will certainly fasten. The discovery of means by which we
can make a weak "constitution" into a strong one is perhaps the least
likely of medical innovations. It would be altogether contrary to the
general spirit of the times anticipated to expect that we shall have
steeled our hearts to the destruction of feeble lives as dangerous
to the race. We are much more likely to go on finding better means
to perpetuate them: and this means that there will always be work for
the doctor, though the infective fevers will have been banished from
the earth. Medicine, therefore, will still aspire. But apart from
what are called occupation-diseases, caused by certain manufacturing
processes (of which the more deadly, as phosphorus match-making,
lead-glazing of earthenware and the manufacture of enamelled iron
will before long certainly be abolished), the elaborate machinery
and rapid travel of the new age must needs exact a certain toll
of death and mutilation. The surgeon will have more to do than the
physician. Frightful accidents will occur from time to time. The maim,
the halt and the blind must pay the price of progress. And it is hardly
possible that nervous diseases and insanity, incident to the pressure
of civilisation, can be eliminated. But certainly the alleviations of
all but the last, and even of that except in its extreme expression
as total dementia, will have advanced to a high standard. We shall
no doubt, for instance, have discovered means of so acting on the
sensory system that we shall be able innocuously and temporarily to
paralyse at any desired spot the nerves which transmit pain. Thus,
during convalescence, the injured will suffer no discomfort except
that of confinement, and our means of amusing the patient by talking
machines that will read and sing to him, and the theatroscopes that
will project before him moving and coloured pictures of life or the
play, will make the sick bed almost a paradise.
As we have seen that, apart from the sentimental reasons which have
been suggested, [19] animal and flesh foods must, for economical
reasons, have been abandoned long before the end of the century, the
grazing of cattle being far too expensive a method of utilising the
soil, we may be quite sure that the sciences connected with agriculture
will receive far greater attention than they now enjoy. It will grow
more important with every decade to obtain the greatest possible
tribute from the portions of land, steadily decreasing in area,
which can be spared from the growing needs of the builder. Every
discovery of the chemist which can be laid under contribution by the
agriculturist will eagerly be seized upon. Every means which can be
devised for replacing what we take from the soil will be utilised
to the full: and of course the inevitable disappearance of the horse
as a means of traction, and of the flocks and herds which now yield
manure, and perhaps the gradual exhaustion of the minerals (as rock
phosphates) from which artificial soil enrichers are prepared, will
make it necessary to rearrange, on safe, economical and convenient
lines, our present plans of sanitation. The insane wastefulness of
draining into the sea cannot long be tolerated. Every conceivable means
of conserving our mundane capital will have to be made use of. In
other ways science will come to the rescue. The farmer's sufferings
from the depredations of vermin of various kinds will perhaps never
be much affected by invention, because all nature is so curiously
interdependent that the eradication of one pest has an awkward way
of intensifying some greater evil: we destroy birds and are punished
by a plague of caterpillars. The accidents of climate, too, can
perhaps only be obviated in a very small measure, though the science
of meteorology, constantly being helped by facilities for better
observation-reporting, will unquestionably help the agriculturist
by giving him timely warnings. It seems hardly possible to doubt
that the eccentricities of climate and the unexpected shifting of the
rainy season in Manchuria during the Russo-Japanese war must have been
caused by the vast atmospheric disturbances created by days and weeks
of cannonading: and of course it is an old theory that heavy gun-fire
"brings down the rain." Military historians say that the number of
wet-day battles altogether exceeds any expectation which could have
been formed without allowing for effects of this sort. When science
has pondered upon the subject, and instituted in an ordered manner
experiments of a kind hitherto never taken very seriously, it may
very well be that some means less violent than the detonation of
explosives may be discovered by the practical meteorologist for
creating disturbances in the atmosphere; and while it may not be
possible to prevent excessive rainfall at inconvenient times, it
seems easy to conceive that when there is moisture in the atmosphere
we may be able to bring it down as rain. Of course this is a very
different thing from breaking up droughts: and artificial rain-making
cannot in itself be anything but a momentary expedient. The effects
of deforestation have for some time been observed and the plan
of improving waterless areas by the contrary process is already
discussed. While it seems rather a "large order" to undertake to
meddle with the balance of atmospheric composition on a large scale,
especially as we know so little of the conditions that even success
might very possibly be attended by unforeseen and perhaps calamitous
results, there is nothing intrinsically absurd in the notion that we
might adopt means on a vast scale for increasing oceanic evaporation
and, utilising the exact foreknowledge of winds and air currents
which we shall certainly have achieved, bring moisture and rain to
arid tracts or countries suffering from drought. The operation would
no doubt require to be stupendous, but the next century is not going
to be afraid of stupendous operations; and anticipating vast and
unforeseen progress in meteorology, it would be hazardous to believe
that no practical use will be made of such progress.
While our knowledge and mastery of the planet we possess, and of its
forces, are being steadily advanced by scientific discovery, and the
researches of the pure scientist are constantly yielding practical
results at first undreamed of, it is impossible to doubt that man's
knowledge of himself will make equal progress. And it is not alone the
physical constitution of man that will be interrogated. Everything
assists the belief that this century will be among other things the
century of psychical advance. We appear to be on the verge of great
discoveries concerning the human mind, and especially concerning
the relation of body to consciousness. Hypnotism has only during a
comparatively short time been the subject of systematic observation,
even in France; but at any time during the last ten years results have
been achieved which, if foreseen a century ago, would certainly have
produced a widespread recrudescence of belief in witchcraft. What
the developed science of a hundred years hence will be capable
of would certainly be a great deal more surprising if we could
foresee it to-day. It is reported from the Salpetrière Hospital
that a woman, under hypnosis, has had the existence of a picture on
a blank sheet of paper suggested to her with such vividness that,
on the suggestion being revived at a subsequent period, even after
a considerable interval, she was able to detect that the "picture"
was upside down, the blank paper having been actually reversed. This
phenomenon is attributed to a great accentuation of the sense of vision
produced by hypnotism, it being supposed that the paper, perfectly
blank on ordinary observation, had really some local irregularity
of colour or surface which the sharpened vision of the subject was
able, unconsciously, to utilise. What secrets in the mechanism
of the senses may not this fore-shadow? Without any recourse to
hypnotism, as we at present understand hypnotism, impressions have,
in a number of instances sufficient to exclude all possibility of
collusion or error, been conveyed from one mind to another without
the use of any of the ordinary means of communication: and it is
shown in experiments seriously conducted by trained observers that
the faculties of thus communicating and receiving impressions can
be steadily cultivated. In other words, it would appear that human
consciousness possesses some sort of emanation, and although certain
"ray" experiments possibly connected with the subject have not received
universal acceptance, it is evident that the future is going to enlarge
considerably our knowledge of the nature of mental process. At present
we know nothing--and it has been said with some rashness that we must
always remain in a like ignorance--of the interval between sense and
consciousness. We know how the ear receives air-vibrations, how it
collects and conducts them to the auditory nerves, carefully protecting
itself, by the action of beautifully ordered springs and cushions,
from the effects of vibrations violent enough to be dangerous to its
own integrity. But even when we have followed vibrations as far as
the nerve, and recognised the subtle variation of its own substance
by which the nerve conducts the impression of them to the brain, we
have no inkling of the means by which the phenomenon of consciousness
which we call "mind" is produced. Well, now that by suggestion alone we
can with perfect precision, and without the use of any air vibration
whatever, cause a hypnotised person (or even a person who has at some
earlier period been hypnotised but has recovered his normal state)
to hear--in his mind alone--sounds which have no objective existence,
just as vividly and clearly as any sounds we can physically produce,
does it seem extravagant to believe that the whole mechanism of sense,
nay, the dark mind-gulf beyond mechanism too, will receive full
illumination from the science of the coming time? Such a discovery
would, of course, throw utterly into shadow anything we have yet
learned of the nature of man. It would bring us a step nearer to
the knowledge of the unknown soul of him. What secrets might it
not carry with it of those mysterious co-partners, mind and body,
thought and brain? With this, the noblest subject that can be proposed
to the intellect of man, the science of a hundred years hence will
assuredly be busy, and imagination pales before the contemplation
of a notion so vast. Limited as we are by the knowledge of our own
time, we cannot even conjecture whither such discoveries might lead
us. All we can affirm is that the whole outlook of man, nay, the
nature of man himself, might very conceivably be changed by them,
and the greatest problems of the thinker may be resolved when we eat
of the fruit tendered us by this tree of the knowledge of good and
evil. Perhaps the soul of man may quail before the revelations in
store, fearing that in the day we eat thereof we shall surely die.