SCIENTIFIC MATERIALISM 89 



of matter to organize itself, to grow into shape, to as- 

 sume definite forms in obedience to tlie definite action of 

 force, is, as I have said, all- pervading. It is in the 

 ground on which you tread, in the water you drink, in 

 the air you breathe. Incipient life, as it were, manifests 

 itself throughout the whole of what we call inorganic 

 nature. 



The forms of the minerals resulting from this play of 

 polar forces are various, and exhibit different degrees of 

 complexity. Men of science avail themselves of all pos- 

 sible means of exploring their molecular architecture. 

 For this purpose they employ in turn, as agents of ex- 

 ploration, light, heat, magnetism, electricity, and sound. 

 Polarized light is especially useful and powerful here. 

 A beam of such light, when sent in among the mole- 

 cules 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 crystallized sugar or sugar- candy is thus 

 strikingly revealed. These actions often display them- 

 selves in chromatic phenomena of great splendor, the 

 play of molecular force being so regulated as to cause 

 the removal of some of the colored constituents of white 

 light, while others are left with increased intensity 

 behind. 



And now let us pass from what we are accustomed 

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

 "When this is examined by polarized light, chromatic 

 phenomena similar to those noticed in crystals are ob- 

 served. And why ? Because the architecture of the 

 grain resembles that of the crystal. In the grain also 



