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BACTERIOLOGY. 



The spirillum of Asiatic cholera is notorious for its 

 slight resistance to desiccation ; according to the ex- 

 haustive investigations of Koch and the above-men- 

 tioned observers, its life-duration is only from one to 

 five hours, depending upon the method of desiccation 

 employed. 



The results of all investigators, however, would seem 

 to indicate that the greatest possible care must be exer- 

 cised in desiccation experiments to come to any positive 

 conclusions; but recently most astonishing results have 

 been obtained with regard to many species usually sup- 

 posed to be particularly sensitive to desiccation, showing 

 that under certain conditions they may retain their 

 vitality in a dry state for a very long time. Thus, 

 Koch found that cholera spirilla lived only a few hours 

 when dry; Kitasato determined their life-duration at 

 fourteen days at most; while Berckholz and various 

 French observers have found that they may, under 

 favorable conditions, live 150 to 200 days. The vary- 

 ing results sometimes reported by different observers in 

 such experiments may be explained by the fact that the 

 conditions under which they were made were different, 

 depending upon the desiccator used, the medium upon 



