438 ELECTRICITY IN THE PHENOMENA OF ANIMAL LIFE. 



the sub-stauce formed. - - - It seems permissible to assume that, 

 in every case of chemical combination, electrical energy may exist 

 before thermic energy, and that the latter may be but the result of a 

 transformation of the former; that, if this way of looking at the facts 

 is but i>artially sustained by experiment, the reason is to be found in 

 our working under conditions which cause the immediate transforma- 

 tion, in whole or m part, of electricity into heat. 



In support of this mode of looking at the facts let us noti(;e that 

 electricity is capable of decomposing a substance without sensibly 

 raising its temperature, while this is far from being true in regard to 

 heat; hence the i)roduct of an electrolysis is much greater than that 

 of a dissociation due to heat alone. It follows that electricity appears 

 to us as endowed with a peculiar and specific character, of which we 

 shall have to take account. - - - 



II.— OF THE UELATION.S EXISTIXG BETWEEN THE PHEXOMENA OK PHY.SICS AND OK 

 CHEMISTUY — UNITY OF THE THYSICAL FOIICES. 



- - - We may, it seems to me, explain all phenoaiona, both phys- 

 ical and chemical, by assuming that every mass of matter (particle, 

 molecule, or atom) is endowed with a specific character which is a 

 mathematical function of its temperature, of its pressure, and of its 

 potential energy or its electrical state.' 



Expanding this proposition, here stated in its most general form, we 

 recognize that it affords us the means of explaining, not only the 

 attractive force acting between the parts of matter of the same kind, 

 but also and equally well the sijecial elective power which characterizes 

 the chemical force called affinity; that it enables us to interpret the 

 variations which this latter force exhibits under the influence of changes 

 in temperature, pressure, or j^revious electrical state (dissociation, 

 action in the nascent state, etc.); that in short this very function of 

 which we are speaking must be the exi)ression of the physical force 

 called cohesion or of the chemical force known as affinity, according as 

 the substances brought together are identical or different in nature. 



All phenomena, physical and chemical, are thus blended, and fall 

 into two great clas.ses: 



( 1 ) Endothermic phenomena, whi(;h consume, absorb, or render latent 

 a certain quantity of external energy; and 



(2) Exothermic phenomena, which set free a part of the energy exist- 

 ing in the potential state in the ingredients which unite in the forma- 

 tion of a new body. 



Let us go back now to what has been said (in I) as to the i)reappear- 

 ance of electrical energy in the act of chemical combination. 



If it be true that chemical and physical phenomena present no essen- 

 tial points of difference, and are but the manifestations of a single and 



' Since tlie potential energy may be expressed as electrical energy. 



