Semi-Centennial Volume. 23 



A Half Century of Bacteriology. 



PRESIDENTIAL ADDRESS, 1918. 



Frank Ulyssks Hbant Agbelius, President, 1917-'1H. 



Of all living things, those that are the smallest are probably the most 

 important. This may not be literally true, but we venture the assertion 

 that it is a close approximation to the truth. And we would venture 

 another statement of about equal breadth: That the nation or people 

 that acts in harmony with the most advanced knowledge of bacteriology 

 will have a great advantage in the world; and that, on the other hand, 

 the group that orders its affairs contrary to such wisdom is as cer- 

 tainly doomed to decline. It is partly because of this belief that I have 

 chosen to discuss what I consider one of the most remarkable and at the 

 same time a most encouraging record of man's achievement. 



We know of no field of human endeavor in which the prophecy, "Ye 

 shall know the truth, and the truth shall make you free," more aptly 

 applies than in that of man and his relation to bacteria and other germs. 

 For untold ages of time he had been enslaved by insidious enemies, 

 scourged by tyrannical foes, thwarted again and again in his endeavors 

 by forces more powerful than he. At the same time other myriads of 

 beings were toiling industriously that soil might exist in which green 

 plants could grow and furnish food for themselves and all other living 

 things. Man now knows that countless tiny, but nevertheless powerful 

 and harmful, germs are at all times ready to cause him suffering and 

 often death, and that they are a real thing to be avoided, or their work 

 counteracted. He also knows that probably many more germs are much 

 more industriously toiling for him in many ways, and that without these 

 latter he could not exist on the earth. Furthermore, and what is very 

 important, he is learning that there are many ways in which he may 

 avoid the possible harm from the one class, and that he may make even 

 greater use of the other helpful class. 



Another peculiar fact in connection with this science is that it has 

 made practically its entire growth since that time, the fiftieth anniver- 

 sary of which we celebrate in this session. Not only this, but very 

 much of this development has been made in a much shorter period than 

 fifty years. 



One cannot take up a discussion such as this without seeing the 

 rather odd fact that to one man alone it has come to lay by far the 

 greater portion of the foundation of such an important science. The 

 world is indebted to Louis Pasteur for a large proportion of the funda- 

 mental facts upon which the science of bacteriology rests, and through 

 this such a far-reaching amelioration of conditions that it may well 

 style him "The World's Helper." 



Fifty years ago Pasteur had found the cause and cure of the two 

 serious diseases of the silk worm and a cause of the souring of milk. 

 He had done considerable work with the fermentation of various sub- 

 stances, showing that such changes were due to the activities of minute 



