136 Annual Report of the Council. 



Throughout his career he instinctively opposed the 

 materialistic and materialising tendencies of the age. The 

 primary motive of all his researches was the demonstra- 

 tion of the existence of an impassable gulf between the 

 principle of life and its products, and the mere physical 

 forces of inorganic matter and its compounds. We 

 detect this idea in his mind in his earliest researches 

 as a chemist on crystallisation, resulting in his dis- 

 covery of the "left-handed" tartrate. The power of a 

 substance in solution to rotate the plane of polarised light 

 was to him associated in some mysterious way with the 

 principle of life ; molecular disymmetry and unsymmetrical 

 crystals suggested the difference between his own right 

 and left hands. Symmetry was uniformity, death; disym- 

 metry was variety, growth, life. Hence when brought 

 face to face with Mitscherlich's active tartrate and inert 

 paratartrate, both apparently identical, Pasteur attacked 

 the problem by searching for his disymmetrical crystals, 

 and proved that the inertness of the paratartrate was due 

 to its being a compound of right and left handed salts 

 which neutralised such other's specific action on the plane 

 of polarisation. We see the same guiding thought in 

 Pasteur's next attempt to establish a specific relation 

 between the right and left handed tartaric acids and the 

 life of specific organisms, demonstrating, for instance, that 

 particular fungi fed on the carbon of the right-handed acid 

 in preference to that of the left-handed acid. From this he 

 was led on to his researches on all fermentation as a vital 

 process due to the life of specific organisms, the nature of 

 the products obtained, whether agreeable, useful, nauseous, 

 or noxious, being dependent on the nature of the organism ; 

 to his long and determined struggle with the believers in 

 spontaneous generation, and to his triumph over them. His 

 great investigations into the silk-worm diseases, and into 

 the "diseases" of wine and of beer, were applications of 



