1 64 BACTERIA IN DAILY LIFE 



represented by a passage from - 190 C. to that of 

 i 5 C. 



The bacillus tuberculosis is admittedly a tough 

 antagonist to deal with, and enjoys an unenviable 

 notoriety for its robust constitution amongst the 

 pathogenic members of the microbial world ; hence 

 a knowledge of its behaviour in these trying cir- 

 cumstances, as we now know them to be to bacterial 

 life, becomes of special interest. Great must have 

 been the investigator's satisfaction, then, when he 

 discovered that the vitality of the consumption 

 bacillus had been so seriously impaired by this 

 treatment that its pathogenic properties collapsed, 

 and the animals which were inoculated with these 

 specimens, instead of with the continuously frozen 

 bacilli, suffered no inconvenience, and remained in 

 good health. 



But although no appreciable change either in 

 the structure, vitality, or malignant properties of 

 the particular bacteria investigated have been noted 

 as resulting from their exposure to extremely low 

 temperatures, yet there is no doubt that a certain 

 proportion of the individual micro-organisms 

 present those probably whose constitution is less 

 robust than their more fortunate associates do 

 succumb under these trying conditions. 



This fact has been well brought out by Dr. 

 Belli, of the University of Padua, in the experi- 



