468 CHEMICAL DISCOVERY AND INVENTION 



from being as yet a justification for the pronouncements which 

 have within the last few years found their way into print and 

 which have too much the air of being uttered ex cathedra. 



The origin of life and hence the origin of mind constitute 

 problems which it is safe to assert will occupy mankind for 

 generations to come. Fascinating as they are, the further we 

 penetrate the more perplexing these problems become, and it 

 is open to those who look at them from the standpoint of the pure 

 physicist or the pure chemist to hold the view that physiology, 

 being the chief handmaid of medicine, would be rendering a 

 greater service to humanity by devoting all her great powers 

 to furthering that branch of science rather than attempting the 

 solution of problems which have every appearance of being in- 

 soluble. At any rate, it is urgently desirable that any statement 

 of the new views should be communicated to the public only 

 when the fundamental facts have been established beyond 

 controversy, and that the bio-chemical and physiological student 

 will not allow his enthusiasm to colour his hypotheses indepen- 

 dently of the light which can be cast upon them. 



The scientific chemist has a large field to himself in which will 

 be found problems as perplexing as those which are presented 

 to the biologist. At present who can say what is chemical 

 affinity or attraction, what is the proper measure of valency, 

 what is the real nature of the relation of the elements to one 

 another ? The term " energy " is freely used, and the physicist 

 speaks commonly of potential energy and distinguishes it from 

 kinetic energy, but he cannot define energy, he can only measure 

 it. " Energy," therefore, is in the same category as " life," but 

 no one would deny its existence because he can no more say 

 exactly what it is than he can define matter, space, or time. 



The future of scientific chemistry will probably depend on the 

 activity of research in two main directions. On the one hand, 

 there will certainly be large additions to the long list of already 

 known definite compounds, especially in the so-called " organic " 

 division of compounds built up on a foundation of carbon as the 

 characteristic element. In this direction little that is new in 

 principle must be expected. But, on the other hand, develop- 

 ments of physical chemistry will doubtless lead to a better 

 knowledge of the laws which regulate chemical change and 

 which connect together chemical constitution and physical 

 properties. The extension of this kind of knowledge will enable 



