364 MICRO-ORGANISMS IN WATER 



Desiccation Experiments Conducted in Diffused Daylight 



(3) Silk threads soaked in anthrax blood and 

 rapidly dried and placed in test-tubes in contact with 

 air, and exposed to diffused light at from 16-22 C. 

 Maximum duration of life of bacilli, seventy days. The 

 final bouillon culture obtained, when inoculated into a 

 guinea-pig, caused death by anthrax in thirty-six hours. 

 If a silk thread which had been exposed for ten days 

 was, however, introduced directly under the skin of a 

 guinea-pig, no ill effects resulted, but if such a thread 

 was placed in bouillon anthrax growths appeared, and 

 some of this culture inoculated into a guinea-pig in- 

 variably induced its death from anthrax. It would 

 appear, suggests Momont, that such dried bacilli when 

 subcutaneously introduced only develop slowly, and 

 before they can do so the migratory cells enclose and 

 destroy them. That the inherent virulence of the 

 bacilli was not destroyed by the above treatment, how- 

 ever, was proved by their subsequent revivification in 

 broth, although such an erroneous conclusion might 

 easily have been arrived at if the negative results ob- 

 tained by direct inoculation of the threads into guinea- 

 pigs had alone been relied on. 



Desiccation Experiments Conducted at High Temperatures 



(4) Exposure to a temperature of 55-58 C. for 

 one hour suffices to destroy all the bacilli present in 

 freshly drawn anthrax blood. If, however, some of this 

 blood was quickly dried, either in test tubes or on cover- 

 glass slips over which it was thinly spread, it was found 

 that the maximum exposure which the bacilli survived 

 was one and a half hour to 92 C., either in the 

 presence or absence of air. The same result was ob- 

 tained whether the blood was taken from an animal 



