424 Chapter XIII 



cholera vibrio but also from Gamaleia's vibrio. As soon as rabbits 

 begin to feed on vegetables they acquire an immunity which is 

 insuperable. 



It is most assuredly not the digestive ferments of the intestine 

 that protect the animal against infection through the intestine. 

 The contents of every part of the small intestine of the Vertebrata 

 permit an abundant development of all sorts of bacteria, and in 

 solutions of trypsin not only do pathogenic and resistant micro- 

 organisms grow luxuriantly, but also saprophytes and the most 

 inoffensive bacteria. Weigert 1 influenced by this fact even saw in it 

 an objection to the theory that the destruction of micro-organisms 

 in the animal, notably that which is effected by the phagocytes, is to 

 be regarded as an act of digestion. It is a remarkable fact that 

 whilst trypsin is so powerless against micro-organisms the intra- 

 cellular ferments, and especially micro-cytase, whose kinship with the 

 group of trypsins is undeniable, are able to bring about their digestion 

 so completely. 



[445] It was thought that among the digestive fluids the bile more 

 especially exerts a definite antiseptic power. It is undeniable that 

 this fluid is not indifferent for certain bacteria. Talma affirms 

 that it is bactericidal for several micro-organisms, especially the 

 diphtheria bacillus. In many of his experiments, however, the bile 

 proved to be incapable of killing micro-organisms introduced directly 

 into the gall-bladder. According to the researches of Gilbert and 

 Dominici 2 the bile does not prevent the abundant development of 

 micro-organisms capable of setting up diseases of the biliary passages, 

 such as the Bacillus coli. I have tried to prevent the multiplication 

 of the cholera vibrio by the addition of bile, but my results were 

 entirely negative. If the bile in an undiluted state has such a slight 

 action upon so many kinds of bacteria, it is evident that we cannot 

 count upon its antiseptic action when it passes into the small 

 intestine, where it is mixed with all sorts of other substances. 



The digestive fluids of the small intestine, either those that are 

 non-bactericidal, the pancreatic juice, or those that are not very 

 active, the bile, are, nevertheless, capable of producing a marked 

 influence on certain poisons, and amongst others on certain microbial 

 toxins. According to the experiments of Nencki and of Mmes Sieber 

 and Schoumow-Simanowski (I.e.), trypsin is much more antitoxic 



1 Fortschr. d. Med., Berlin, 1888, Bd. vi, S. 809. 

 * Compt. rend. Soc. de biol., Paris, 1894, p. 38. 



