SPIRILLUM CHOLERvE ASIATICS. 441 



substrata, and by the other conditions of life, and also 

 what is the nature of the toxic substance. 



Some experiments have been made on man with Experiments 

 cholera dejecta or cultivations, partly intentionally and 

 partly unintentionally. Thus during the last cholera Experiments 

 epidemic in Paris Bochefontaine swallowed pills con- tJin^anf 01 '" 

 taining cholera dejecta, and Klein in Bombay drank a Klein, 

 fluid said to contain comma bacilli. In neither case did 

 illness follow ; but in neither was there any proof that 

 living comma bacilli were present in the material taken. 

 And besides, the negative, like the positive, result of 

 these two experiments was of no value in reference to 

 the etiology of the disease, as it is well known that by 

 no means every man who swallows the infective material 

 suffers from cholera, but only those who are predisposed 

 to infection ; and, on the other hand, had illness followed 

 these infective experiments it might quite well have 

 been objected that it was due to some other cause, for 

 the experiments were made in a place where cholera was 

 prevalent. 



On the other hand, another experiment unintentionally Infection of 

 made on man furnishes a further support for the etio- tivations of 

 logical significance of the comma bacilli. One of those comma bacilli, 

 who took part in the courses on cholera, which were 

 held in Berlin in November, 1884, under Koch's direc- 

 tion, became ill with somewhat severe symptoms of 

 cholera. At this time there was no case of cholera 

 either in Berlin or in Germany ; the only possible source 

 of the infection was the pure cultivations of comma 

 bacilli with which the physician in question was work- 

 ing ; and this physician was more predisposed to infec- 

 tion by these cultivations than any of the other students, 

 because for some days he had suffered from gastric dis- 

 turbances and slight diarrhoea. After the appearance of 

 the symptoms of cholera the watery dejecta of the patient 

 were examined, and \vere found to contain very large 

 numbers of comma bacilli which coincided in all respects 

 with those obtained by Koch from cholera dejecta in 

 India. 



There is, as yet, no definite proof that the virulent 



