CHAPTER V 



THE PROBLEMS OF SOLUTION 



" If we accept the hypothesis that the elementary substances 

 are composed of atoms, we cannot avoid concluding that electricity 

 also ... is divided into definite elementary portions, which behave 

 like atoms of electricity." — H. vON Helmholtz, "Faraday 

 Lecture," 1881. 



To one inexperienced in the problems which 

 confront the workers in the world of natural 

 science, the whole question of solution and its 

 attendant phenomena may appear, at first sight, 

 of small account. Yet the study of these same 

 phenomena, and the unravelling of their intricate 

 connections, are of fundamental importance. 

 Furthermore, as the work of the last twenty 

 years has shown, the problems involved are of 

 increasing interest, not only from the point of 

 view of physics and chemistry, but also, and 

 perhaps especially, from the physiological stand- 

 point. More and more the reactions of inorganic 

 substances, whether liquid or solid, are referred 

 to their properties in a state of solution, while 

 every process of life to be investigated by the 

 biologist seems capable of interpretation only 

 through attention to the conditions thereby in- 

 volved. Moreover, most chemical actions, especi- 

 ally those examined easily in the laboratory, occur 

 between substances one or more of which are 

 actually in the liquid state ; while the application 



98 



