CHAPTER VII

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.