208 BOARD OF AGRICULTURE. 



of the veterinarian and the medical man to the people, that 

 it would, 1 think, be interesting to review, briefly, bis 

 career and some of his methods, before proceeding. 



Pasteur and his work is a subject on which a small volume 

 might easily be written, but we have time to devote only a 

 few words to him and to what he has done. 



Louis Pasteur was born about sixty-five years ago, and 

 was educated as a chemist ; in 1854 he was appointed pro- 

 fessor of chemistry at Strasburg, and soon after was made 

 "Dean of the Faculty of Sciences," at Lille. During his 

 investigations and experiments, his attention was called to 

 microscopic forms of life seen in connection with certain 

 chemical changes. Some of these fungi had been observed 

 before, but they had been supposed to retard the chemical 

 changes rather than to assist them, and it was thought that 

 these changes were due to the action of oxygen. Pasteur 

 was the first to find out that very many of these chemical 

 changes were due to the presence of these organisms, and 

 could not take place without them. He demonstrated that 

 the formation of alcohol was due to the presence of the yeast 

 plant. Soon after he discovered the bacterium of the lactic 

 acid ferment, and the acetic acid ferment ; the acetic acid 

 ferment beino; what we know as the " mother of vinegar." 

 He also investigated other similar ferments, which we have 

 not time to mention. Pasteur thus gradually became a 

 biologist, instead of a chemist, and his time was henceforth 

 to be devoted to the study of the lower forms of vegetable 

 life, especially those which are now believed to be the 

 causes of various contao'ious diseases of animals and man, 

 and popularly known as " disease germs." 



Pasteur's first w^ork in the field of animal plagues, if you 

 will allow me to speak of a worm as an animal, was his 

 investigation of the silk-worm disease, which had almost 

 destroyed the silk industry of France. He occupied himself 

 with these researches from 1865 to 1869, when he brought 

 his labors to a successful termination, and restored to his 

 country what might be called a lost industry. He found 

 that the moths sufiered fi'om a disease due to a microscopic 

 organism, and that this disorder was transmitted from the 

 female moths to the eggs, being both hereditary and con- 



