December 7, 191 1] 



NATURE 



193 



n the coal and oil of the earth, at present being exploited, 

 tfe exhausted. 



So far as I am aware, the results of modern discovery 

 lave had no effect in weakening our belief in the truth of 

 he great principle of the conservation of energy as defined 

 n what is commonly called the first law of thermo- 

 lynamics, which law is really a statement that the sum 

 )i energy in the universe, just as the amount of matter, 

 ^ a constant, and cannot be either increased or diminished 

 Jy any means whatever. 



' When, however, we come to the so-called second law, 

 vhich, as stated by Clausius, is that it is impossible for a 

 elf-acting machine, unaided by external agency, to convey 

 leat from one body to another at a higher temperature, 

 >r, as given by Lord Kelvin in a somewhat different form, 

 it is impossible by means of inanimate material 

 > to derive mechanical effect from any portion of 

 i -r by cooling it below the temperature of the coldest 

 it tile surrounding objects, we find that even the authors 

 )t these statements are prepared to admit that this second 

 aw stands on a totally different basis from the first law, 

 ^nd, as declared by Maxwell, can only be said to be 

 itatistically correct, or correct only when we are dealing 

 vith masses of matter and not with individual molecules. 



Indeed, it was in this connection that Maxwell pro- 

 >ounded his celebrated proposition, in which he supposes 

 hat a demon who could see individual molecules, and was 

 )ossessed of superhuman dexterity, could open and close 

 m aperture in a partition dividing a vessel into two 

 leparate portions, A and B, so as to allow only the swifter 

 nolecules to pass from A to B, and only the slower ones 

 rom B to A, in which case, without the expenditure of 

 vork, the temperature of B would be raised and that of 

 \. lowered, in contradiction to this second law. 



It will further be observed that in the definitions quoted 

 ibove Clausius is careful to qualify his statement by words 



the effect that there must be no external aid, while 

 >ord Kelvin is even still more specific, and expressly limits 

 he whole law to things inanimate. 



Now lately, in London, we have had — I suppose 

 s the result of Prof. Bergson's remarkable writings — one 

 f the usual periodic outbreaks of more or less meta- 

 hysical discussion, and, incidentally, there has been raised 

 uite seriously the question as to whether living organisms 

 re subject to these laws of thermodynamics or not. 



So far as the first law is concerned, there seems to be 

 omplete agreement that there can be no question of any 

 ut an affirmative reply, as we can scarcely suppose living 

 'lings to be capable of creating energy any more than of 

 reating matter. 



But when we come to the second law there are appar- 

 ntly those who hold that it is different — who, in fact, 

 elieve that there is good reason for doubting whether this 

 scond law, which prevents us by the use of any mere 

 lachine from getting mechanical effect from the general 

 tock of heat, applies to living organisms at all. Indeed, 

 n the contrary, it is contended that it is probable that, 



1 the case of certain animate bodies, this is actually being 

 ccomplished all the time ; in other words, that there exist 

 ving things which in some fashion or other do very much 

 'hat was the business of Maxwell's demons to do, and in 

 lis manner extract the energy that they require from the 

 eneral stock. Here, obviously, is a most important 

 latter for investigation, and one, having regard to its 

 jmbined physiological and physical aspects, peculiarly 

 dapted to be tackled by the members of the Rontgen 

 ociety, that is to say, if those who put it forward can 

 lake out a sufficient case to make actual experiment 

 'orth while. 



Thf^ interest of the question will be especially apparent 

 ) anyone who has seen the so-called Brownlan movements 

 'hich can be perceived by ultramicroscopic methods in 

 nely divided solid matter, such as particles of colloidal 

 old suspended in a liquid or of tobacco smoke in a gas. 

 hese movements are now believed to be due to the actual 

 >stling of the minute particles by the moving molecules 

 lemselves, and give the most wonderful notion of the 

 ;asr>Iess state of agitation that exists among the molecules 

 F all substances at any temperature above that of the 

 Itlmate zero, and the vast amount of enorgy that is stored 

 \ these perpetual movements. 



NO. ^TO-. VOL. 88] 



Indeed, so remarkable do the Brownian movements 

 appear that their original discoverer, who detected them 

 in finely divided vegetable matter, came to the conclusion 

 that the particles were alive. 



To return to the main question, however, without pre- 

 suming to pronounce any opinion one way or another on 

 the very startling idea that living matter is not always 

 subject to the second law of thermodynamics, but finds 

 means, in some cases at all events, to evade its provision, 

 I desire to direct attention to the stupendous consequences 

 that would follow could such a view be established. Here, 

 at last, we should have the equivalent of the perpetually 

 burning lamp of the story books, which consumed no oil ; 

 the perpetual fire of the burning bush, which required no 

 fuel. We should have immediately to hand the means of 

 producing the perpetual motion dreamed of by mediaeval 

 philosophers. We should only have to cultivate the right 

 kind of organisms in sufficient masses, and they would do 

 all this for us. Moreover, there would be nothing lost ; 

 the heat that was thus accumulated locally for our needs 

 would dissipate itself again into the common store, as 

 would also the mechanical eft'ects after they had done their 

 work. The unordered molecular motions of which the 

 Brownian movements give us an indication — motions which 

 constitute heat — would merely be directed for a time in the 

 particular manner needful to give us the power that we 

 require. Life would be the directing force ; but it would 

 be a directing force only, and would do no work. 



It is a fascinating prospect, giving us a glimpse of what 

 some may perhaps Uiink is destined to take the place of 

 fuel a few hundred years hence, when the latter is all 

 exhausted and before means have been found to unlock the 

 still greater stores of atomic energy that have already been 

 alluded to. To those, however, who have been brought up 

 to rely on the orthodox doctrines of thermodynamics, it 

 seems not only very revolutionary, but also very heterodox 

 from a physical point of view. Personally, as one totally 

 ignorant of biology, I am only here concerned to point out 

 the inevitable consequence of admitting that living matter 

 is not subject to the second thermodynamic law, a proposi- 

 tion which I venture to believe has never before now been 

 put forward seriously in any responsible quarters. 



Among the many scientific problems that await solution, 

 problems which, if satisfactorily solved, would have an 

 enormous effect on the habits of mankind, is that of 

 distant electric vision, or the power to see objects a great 

 way off by electrical means ; in other words, to do for the 

 sense of sight what the telephone has done for the sense of 

 hearing. Indeed, if this extension of our sense of vision 

 was obtained, we could well afford to dispense with any 

 extension of our other senses, namely, those of taste, smell, 

 and touch, the senses of sight and of hearing being, for 

 all ordinary purposes, much more important to us than are 

 the others. 



So long ago as the year 1908, in connection with a 

 paper published in Nature by the late Mr. Shelford Bid- 

 well, I wrote a letter in that journal suggesting that the 

 difficulty of obtaining the necessary enormous numbers of 

 synchronised operations per second could possibly be solved 

 by the employment of two beams of kathode rays, one at 

 the transmitting and one at the receiving station, sychron- 

 ously deflected by the varying fields of two electromagnets 

 placed at right angles to one another and energised by two 

 alternating electric currents of widely different frequencies, 

 so that the moving extremities of the two beams would be 

 caused to sweep synchronously over the whole of the re- 

 quired surfaces within the one-tenth of a second necessary 

 to take advantage of visual persistence ; and that, so far 

 as the receiving apparatus was concerned, the moving 

 kathode beam would only have to be arranged to impinge 

 on a sufficiently sensitive fluorescent screen, and, given 

 suitable variations in its intensity, to obtain the desired 

 result. As, since that date, I have several times been 

 asked to explain more in detail this idea, I now propose 

 to do so, though it must be distinctly understood that my 

 plan is an idea only, and that the apparatus has never been 

 constructed. Furthermore, I would explain that I do not 

 for a moment suppose it could be got to work without a 

 great deal of experiment, and probably much modification. 

 It is, indeed, only an effort of my imagination, and can 

 be useful merely as a suggestion of a direction in which 



