82 FRAGMENTS OF SCIENCE. 



of complexity. Men of science avail themselves of all 

 possible means of exploring their molecular architecture. 

 For this purpose they employ in turn, as agents of 

 exploration, light, heat, magnetism, electricity, and 

 sound. Polarised light is especially useful and powerful 

 here. A beam of such light, when sent in among the 

 molecules of a crystal, is acted on by them, and from this 

 action we infer with more or less clearness the manner in 

 which the molecules are arranged. That differences, 

 for example, exist between the inner structure of rock- 

 salt and that of crystallised sugar or sugar-candy, is 

 thus strikingly revealed. These actions often display 

 themselves in chromatic phenomena of great splendour, 

 the play of molecular force being so regulated as to 

 cause the removal of some of the coloured constituents 

 of white light, while others are left with increased in- 

 tensity behind. 



And now let us pass from what we are accustomed 

 to regard .as a dead mineral, to a living grain of corn. 

 When this is examined by polarised light, chromatic 

 phenomena similar to those noticed in crystals are 

 observed. And why ? Because the architecture of the 

 grain resembles that of the crystal. In the grain also 

 the molecules are set in definite positions, and in 

 accordance with their arrangement they act upon the 

 light. But what has built together the molecules of the 

 corn ? Regarding crystalline architecture, I have already 

 said that you may, if you please, consider the atoms and 

 molecules to be placed in position by a Power external 

 to themselves. The same hypothesis is open to you now. 

 But if in the case of crystals you have rejected this 

 notion of an external architect, I think you are bound 

 to reject it in the case of the grain, and to conclude 

 that the molecules of the corn, also, are posited by the 

 forces with which they act upon each other. It would 



