NON-MATHEMATICAL SCIENCES 169 



with an accuracy of one part in ten million. 

 Later he has the genius to discover that a simple 

 model following laws closely akin to those of 

 classical mechanics and electromagnetics would 

 give the phenomena which have been observed. 

 From his simple model he proceeds to more com- 

 plex ones, involving a greater number of parts, 

 and calculates as best he can the perturbations 

 produced in part of his model by another part. 

 And thus from his model as a center he works 

 out into the unknown. 



The method of the chemist is radically differ- 

 ent. It is convergent rather than divergent. His 

 data are far less exact, but they are vastly more 

 numerous. Some are rough measurements, but 

 the greater part are not even metrical in char- 

 acter. They are based upon the observations of 

 thousands of different substances, and from 

 these observations come rough generalizations 

 like the periodic law of Mendeleef. And so he 

 works gradually through the complex molecule 

 into the very heart of the atom. 



The history of science shows that we must 

 not rank either method higher than the other 

 in power or attainments. Yet those who follow 

 the first of these two great methods of scientific 

 inquiry are apt to look askance at the results 



