W. a. 8TEVEN8OX. 99-(69 



vital entity should be discovered, if anywhere, for here 

 we have the primal seat of life, the very fountain of ge 

 netic power. 



Analysis, however, finds room for it in nutrienl 

 action no more than in the mysteries which lie concealed 

 in every expression of energy throughout nature's do- 

 main. Why will friction of a glass tube produce a con- 

 dition or property which will repel pith balls, while 

 friction of sealing-wax produces a condition which will 

 attract them? Are these movements caused by some 

 kind of life principle developed in so simple a way? 

 No ; they come from positive and negative electricity 

 evolved by friction, and with this answer, science asserts 

 the explanation is complete. When asked what is elec- 

 tricity, beyond a special display of energy, there is no 

 answer. 



If we question the various organic functions of the 

 body, physical and chemical laws alone confront us. A 

 muscle contracts according to mechanical laws, and its 

 work is expressed in mechanical equivalents. Electric 

 tension is lost, heat is evolved, carbon dioxide ap- 

 pears, and the muscular tissue, before neutral in reaction, 

 is now acid. Whatever may be the nature of the vital 

 force, if such there be, operating in muscular contraction, 

 it, at least, is not independent of physical and chemical 

 forces, and the evidence is cumulative that these will 

 alone explain the phenomenon. Respiration is purely a 

 chemical process, in harmony with the laws of gaseous 

 diffusion. 



Circulation, with its pumps, pipes and valves, is ;i hy- 

 draulic operation. Absorption is osmotic, and a similar 

 selective affinity for special things is exhibited in inor- 

 ganic material, as well as in animal membranes. 



There seems no good reason why we should hesitate to 

 regard the •• vital" force as correlated with the physical 

 forces known to us as heat, light, electricity and actin- 

 ism. That some relation exists there can be no doubt, 

 for the effect of physical forces upon organic life is mark- 

 ed, and their energy is made potential in the tissues of 

 both vegetables and animals. This potential energy is, 

 after a time, transformed into active energy and new phe 

 nomena result. 



