n6 



SCIENCE. 



two directions at least, in its rate of action and of its rela- 

 tive energy, we may already measure thought, as we meas- 

 ure any other form of energy, by the effects it produces. 



Passing now to the consideration of the general question 

 of the translormation of energy which is effected by living 

 beings, attention may be called to one or two points in gen- 

 eral physics, as bearing upon its solution. The great law 

 of the dissipation of energy, as modified by Thomson from 

 the statement of Clausius, is thus stated : "The entropy of 

 the universe tends to zero." In other words, the energy of 

 the universe available for transmulation is approaching ex- 

 tinction. This conclusion is based upon the fact that while 

 every form of energy can be completely converted into heat, 

 heat cannot be completely converted into other forms of 

 energy, nor these into each other. Hence it arises that en- 

 ergy is being gradually dissipated as heat. Moreover, since 

 transformation can only result when heat passes irom a 

 higher to a lower temperature, it follows that when that per- 

 fect equilibrium of temperaiure is reached toward which 

 events are tending, there can be no other energy than heat ; 

 and this absolutely /nconvertible, irrevocable. To apply 

 this law to the present case, the muscle, for example, is a 

 machine for transforming the energy of food into work.. 

 Since, consequently, this conversion is not complete, it fol- 

 lows that heat must appear as a necessary result of muscu 

 lar action. The heat of animal life, consequently, is not 

 heat especially provided ; it is simply the heat which inev- 

 itably results from an incomplete conversion of energy. 



Again, the form of chemical action thus far assumed by 

 physiologists fo account for the energy of the living animal 

 has been combustion. But the science of thermo-chemistry, 

 as developed in late years by Berthelot and Thomsen, has 

 proved, that direct union of chemical substances may not 

 only not evolve heat, but may actually absorb it. It ap- 

 pears, too, that thermal changes accompany all forms of 

 chemical change, those of decomposition and exchange as 

 well as those of synthesis. The animal absorbs highly 

 complex substances as food, capable of innumerable stages 

 of retrogressive metamorphosis before elimination. In 

 each of these stages heat is evolved, being the energy suc- 

 cessively stored up by the plant when it repeated these 

 stages in the inverse order. 



Another point of interest has reference to the modern 

 views of capillarity. In 1838, J. W. Draper showed that 

 capillarity is an electrical phenomena. Quite recently, 

 Lippmann has developed and extended this view and fully 

 confirmed it. Whenever the free surface of a liquid, curved 

 by capillary action, is electrified it changes its form ; and 

 conversely, when such a surface is made by mechanical 

 means to change its form, an electromotive force is de- 

 veloped. Based upon this principle Lippmann constructed 

 a capillary reversible engine and an extremely sensi- 

 tive capillary electometer. The former, when a current of 

 electricity was applied to it, developed mechanical work 

 and ran as a motor. When turned by hand, it became an 

 electromotor. In the animal organism there are it is true 

 but a few free surfaces where this action can take place. 

 But Gore has shown that the same phenomenon appears 

 between two liquids in contact, their boundary being al- 

 tered in character by electrification. Indeed, when we con- 

 sider the production of electricity by osmose, and of heat 

 and electricity both, by imbibition, both capillary phenom- 

 ena, the wonder is not that so much energy is evolved by 

 the organism, but that it is so little. If the physical and 

 chemical changes which take place within the body took 

 place without it, there would be an abundant evolution of 

 energy. Can we doubt that these changes are the cause of 

 the energy exhibited by the organism ? 



Thus far, when we have spoken of a living being, we 

 have had reference to the organism as a whole, and this of 

 a rather complex kind. In this view of the case, however, 

 we find that biological micioscopists do not agree witli us. 

 " The cell alone," says Kiiss, " is the essentially vital cle- 

 ment." Says Beale, — "There is in living matter nothing 

 which can be called a mechanism, nothing in which structure 

 can be discerned. A little transparent colorless materia! is 

 the seat of these marvellous powers or properties which the 

 form, structure and function of the tissues and organs 

 of all living things are determined." And again, " 1 low- 

 ever much organisms and their tissues in their fully formed 

 state may vary as regards the character, properties and 



composition of the formed material, all were first in the 

 condition of clear, transparent, structureless, formless liv- 

 ing matter." So Ranvier : '' Cellular elements possess all 

 the essential vital properties of the complete organism." 

 And Allman, in his address as President of the British 

 Association last year, is still more explicit. " Every living 

 being," he says, "has protoplasm as the essential matter of 

 every living element of its structure." " No one who con- 

 templates this spontaneously moving matter can deny that 

 it is alive. Liquid as it is, it is a living liquid ; organless 

 and structureless as it is, it manifests the essential pheno- 

 mena of life." " Coextensive with the whole of the organic 

 nature — every vital act being referable to some mode or 

 property of protoplasm, it becomes to the biologist what 

 the ether is to the physicist." From these quotations it 

 would seem that even in the highest animal there is noth- 

 ing living but protoplasm or germinal matter " transparent, 

 colorless, and, as far as can be ascertained by examination 

 with the highest powers of the microscope, perfectly struc- 

 tureless. It exhibits these same characters at every period 

 of its existence." Neither the contractile tissue of the 

 muscle, the axis-cylinder of the nerve, nor the secreting 

 cell of the gland, is living, according to Beale. Hence it 

 would be fair to draw the inference that no vital force 

 should be required to explain the phenomena of the non- 

 living matter of the body, such as the contraction of the 

 muscle or the function of the nerve. If this be conceded it 

 is a great point gained ; since the phenomenon of life be- 

 comes vastly simplified when we have to account for it 

 only as exhibited in this one single form of living matter, 

 protoplasm. In describing its properties, Allman includes 

 this remarkable mobility, these spontaneous movements, 

 and says, "They result from its proper irritability.its essential 

 constitution as living matter. From the facts there is but 

 one legitimate conclusion, that life is a property of proto- 

 plasm." Beale, however, will not allow that life is " a 

 property" of protoplasm. "It cannot be a property of 

 matter," he says, " because it is in all respects essentially 

 different in its actions from all acknowledged properties of 

 matter." But the properties of bodies are only the char- 

 acters by which we differentiate them. Two bodies having 

 the same properties would only be two portions of the same 

 substance. Because life, therefore, is unlike other prop- 

 erties of matter, it by no means follows that it is not a 

 property of matter. No dictum is more absolute in science 

 than the one which predicates properties upon constitution. 

 To say that this property exhibited by protoplasm, marvel- 

 lous and even unique though it be, is not a natural result 

 of the constitution of the matter itself, but is due to an un- 

 known entity, a tertium quid, which inhabits and controls 

 it, is opposed to all scientific analogy and experience. To 

 the statement of the vitalist that there is no evidence that 

 life is a property of matter, we may reply with emphasis 

 that there is not the slightest proof that it is not. 



Chemistry tells us that complexity of composition in- 

 volves complexity of properties. The grand progress which 

 Organic Chemistry has made in recent times has been ow- 

 ing to the distinct recognition of the influence of structure 

 upon properties. Isomerism is one of its most significant 

 developments. The number of possible insomers increases 

 enormously with the complexity of the molecule. Granted 

 that we now know several of the proteid group of substancs : 

 how many thousand may there be yet to know? Bodies of 

 such extreme complexity of constitution may well have an 

 indefinite number of isomers. Not only does chemistry not 

 say that there cannot be such a thing but she encourages 

 the expectation that there will be yet found the precise 

 proteid of which the changes of protoplasm are properties. 

 The rapid march of recent organic synthesis makes it quite 

 certain that every distinct chemical substance of the living 

 body will ultimately be produced in the laboratory ; and 

 this from inorganic materials. Given only the exact con- 

 stitution of a compound, and its synthesis follows. When, 

 therefore, the chemist shall succeed in producing a mass 

 constitutionally identical with protoplasmic albumin, there 

 is every reason to expect that it will exhibit all the pheno- 

 mena which characterize its life ; and this equally whether 

 protoplasm be a single substance or a mixture of several 

 closely allied substances. 



But here a word should be said concerning a remark- 

 able physical condition issumed by matter in organ-* 



