CHOLERA. l6l 



particles in suspension and of pieces of mud," development occurs, " especi- 

 ally on the floating solid fragments. " Koch's experiments, however, have 

 shown that cholera bacilli mixed with spring water were still alive after the 

 lapse of a period of thirty days. In Berlin sewer water they lived only six 

 to seven days, mixed vrith excrement only twenty-seven hours, and in cess- 

 pool water they were not alive at the end of twenty-four hours. Babes' 

 experiments, as already stated, did not bear out these statistics in their 

 entirety. 



Infection through the agency of milk has aheady been 

 mentioned, and water has been referred to as a vehicle by 

 which the bacillus may be carried. Macnamara gives an 

 experience of infection through water, for the absolute 

 accuracy of which, in the case of such a skilled observer, 

 Koch contends there can be little doubt. In a region in 

 which no cholera prevailed, the dejecta from a sporadic 

 case of cholera became accidentally mixed with some water, 

 which, after remaining exposed to the heat of the sun for a 

 whole day, was partaken of by nineteen persons, of whom 

 five were attacked with unmistakable cholera within thirty- 

 six hours ; the evidence here given was so conclusive that 

 little doubt can be entertained as to the relation of the 

 dejecta to the water, and to the subsequent cases of cholera. 

 It should here be mentioned, however, that Klein, who does 

 not believe in the specific nature of Koch's cholera organism, 

 in order to prove his position, drank a quantity of fluid 

 which was said to contain cholera material without feel- 

 ing any ill effects ; and that Bochfontaine swallowed 

 cholera dejecta in pills without suffering any incovenience ; 

 but in both cases there is ample evidence that the persons 

 experimenting upon themselves were suiFering from no gas- 

 tric or intestinal derangement of any kind, and that the 

 gastric juice was sufficiently active to prevent the multipli- 

 cation of the cholera organisms, and it is probable that the 

 fourteen men of the nineteen not attacked in Macnamara's 

 case were in a similar impregnable condition. As positive 

 evidence to set against the above is a most striking case that 

 occurred in connection with Koch's cholera courses, carried 

 on in the Hygienic Institute in Berlin. A doctor who had 

 been for eight days engaged on work in the cholera course 

 became affected with a slight disturbance of digestion, which 

 was accompanied by diarrhoea ; he continued to get worse, 

 and was at length so ill that he started for home, where he 

 was almost immediately attacked with symptoms of true 



12 



