PRESIDENTIAL ADDRESS XUI 



in it, and consumes it. This inebriate likes its liquor weak and 

 won't have anything to do with drinks containing more than 

 about 10 per cent, of alcohol, but it effectually alters these and 

 under its depraved influence reduces them to the sourest vinegar. 

 Acetous fermentation — an oxidation of alcohol — has been 

 brought about by the growth of bacteria. *^^' 



Alcohol. Oxygen. Acetic Acid. Water. 



Besides these fermentations mentioned, are the Lactic 

 {BacilliiK ticidi lactici) and the Butyric (IjuciUus biiti/ricus). 



Pathogenetic Bacteria or the Micro-organisms of the 

 Infections of Animal, and Plant Life. — It has been thoroughly 

 established that some of the diseases to which flesh is heir are 

 induced by specific germs of bacterial origin. 



A list is given of 17 diseases of more or less established 

 bacteriology, 19 are catalogued as uncertain, 5 appear as com- 

 municable from animals to man, and 2 are due to protozoa ; a. 

 total of 43 ailments. <25 to 43) 



Now that the action of the Zymogens is uuderstood — the 

 breaking down complex organic substances into simpler products 

 — it may naturally lead one to suspect that the morbiferous 

 micro-organisms, during their proliferation in the human fluids 

 and tissues, effect changes not unallied to fermentation ; and 

 long before the days of bacteriology something of the kind was 

 believed, and many diseases were grouped as Zi/motir, a term 

 now practically extinct. 



In the normal blood and tissues, so far as is known, no 

 micro-organisms exist ; but they are found on the skin and 

 on the mucous surfaces. In the mouth they are plentiful, and 

 quite ten years ago Miller described and cultivated some fifty 

 different kinds found there, and from the number on the mucous 

 surface of the prima via, it has been argued that the process of 

 digestion is not wholly independent of bacterial aid.. 



This is neither the time nor the place to dwell on the 

 influences of bacterial activity, on infection or contagion, on 

 susceptibility or predisposition, and on immunity — factors which 

 have to be taken into account when war between parasite and 

 host is declared or waged. Suffice that an invasion by the former 

 may be successfully resisted by the P/tacoci/tes— (44-45-46) tj^e police- 

 men of the blood current — who, alarmed by the intrusion of an 

 enemy, pounce upon him and destroy him by summarily eating- 



