384 PHYSIOLOGY, CHEMISTRY AND MORPHOLOGY. 



developed by til em is trausformed into function; liow, in tlie compli- 

 cated meclianism of our tissues, it comes to manifest itself in tlie form 

 of heat, electricity, muscular movement, secretion, and nervous activity. 

 Is not tlie same coal burned in the different engines'? Yet liow many 

 varied effects may be manifested by tliese different causes! Altliouiih 

 tbe chemical basis of their function may be the same, does not that 

 function remain invariable, even when the nature of the fuel consumed 

 in the furnace varies"? Consider the immense variety of metabolisms of 

 animals and plants; coippare that with the admirable functional unity 

 of these beings, and tell me if that does not suffice to show how slight 

 is the importance of chemical work in the development of a special 

 function. 



All this appears to me to be forgotten by those who, impelled by that 

 enthusiasm for system now so much in vogue, see in every organic func- 

 tion a chemical tact and nothing else. We, on the contrary, recognize 

 truly that chemical action is the cause of the energy dis]>layed, but we 

 can not forget that function is self-determined, transforming that energy 

 and presenting it under an infinite number of manifestations. 



The admirable researches of Eaoul Tictet' show clearly the share 

 that in functional acts ought to be ascribed to chemical reactions and 

 that Avhich should be given to the organization of the tissues. This 

 experimenter has recently shown that a very low temperature — 100^ 

 below zero — stops all chemical reaction, no matter what; even sulphuric 

 acid and nitric acid no longer combine with soda, potash, and ammonia. 

 These experiments .show that at absolute zero heterogeneous l)odics no 

 longer react upon each other, whatever may be their affinities, for the 

 reason, according to Pictet, that they have attained the limit of cohe- 

 sion, and that no sufficient force brings the atoms near enough to each 

 other to get them within the sphere of each other's activity. If, on the 

 other hand, we keep living things in a refrigerating apparatus for a 

 long time, it may be observed that after thawing they again resume 

 their functions in an absolutely normal manner.' Pictet thus ol)tainsa 

 complete restoration of the manifestations of life in bacilli and seeds 

 kept at 200° below zero. Vibratile cilia that have supported a tempera- 

 ture of 00° and fish that have been so frozen as to form a solid mass 

 with the ice in which they are embedded and have become as brittle as 

 glass may also be recalled to life. 



These experiments are of great importance, inasmuch as they demon- 

 strate that an arrest of chemical activity in the tissues does not destroy 

 the i^otential conditions of life, and that the latter finds the basis fi)r its 

 continuity rather in the organization of the body, that is in its structural 

 mechanism. To use a somewhat crude illustration, the usual relation 

 of chemistry to the functional activity of a living being is like that of 



' Raoul Pictet. "Essai d'une methode g6ni5rale dc syntbese chimique," Archives des 

 sciences ph,ysi([ues et uaturelles, T. XX VIII, page 397, 1892. 



-Raoul Pictet. "La vie et les basses temijoratures," Revue Scientifique, T. LII, 

 page 577, 1893. 



