CHAPTER VII. 



EXPERIMENTAL PRODUCTION OF CHOLERA. 



KOCH in his first pamphlet (p. 27) told us that he has 

 made every imaginable effort to produce cholera in animals 

 experimentally. The experiments of feeding white mice with 

 cholera dejecta, first made by Tiersch and then by Burden 

 Sanderson, were repeated by Koch over and over again on 

 fifty white mice fed with fresh material (dejecta of cholera 

 patients, and the contents of the intestine of cholera corpses) 

 and with choleraic material after it had begun to decompose, 

 but no result whatever followed ; the mice remained healthy. 

 " We then made experiments on monkeys, cats, poultry, 

 dogs and various other animals that we were able to get hold 

 of, but we were never able to arrive at anything in animals 

 similar to the cholera process. In precisely the same manner 

 we made experiments with the cultivations of comma-bacilli ; 

 these were given as food in all stages of development. 

 When experiments were made by feeding animals with large 

 quantities of comma-bacilli, on killing them and examining 

 the contents of their stomachs and intestines with a view to 

 find comma-bacilli, it was seen that the comma-bacilli had 

 already perished in the stomach, and had usually not reached 



the intestinal canal The comma-bacilli had been 



destroyed in the stomachs of these animals. . . . The 



