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are renewed, and the syringe boiled and cleaned, after 

 every series of operations. 



(n) All vessels coming in contact with the deuxieme or 

 the virulent vaccines have to be boiled before cleaning. 



1,354. Some general remarks regarding the effect of 

 temperature on bacillus anthracis may be noted here for 

 guidance in the above practices : 



(1) The bacilli are not cultivated under 16 C. 



(2) At 1 6 C. they do not give spores, at least not for a 

 long time. 



(3) At 45 C. they are no longer capable of cultivation 

 in chicken broth. 



(4) At 42 to 45 C. the culture goes on rapidly, but only 

 of filaments. Scarcely any spore formation takes place at 

 this temperature. This is the temperature used by Pasteur 

 to attenuate his vaccine, about 12 days being allowed for 

 the second or stronger vaccine, and 20 days for the weaker 

 or first vaccine. 



(5) The most favourable temperature for the development 

 of the filamentous as well as the sporular states of the 

 bacilli is between 30 and 35 C. 



^6) The filamentous bacilli are killed by a temperature 

 of over 60 C., excess of CO 2 gas, or alcohol. 



(7) Spores, however, are not killed under these condi- 

 tions. They retain their vitality in vacuum also. Spores 

 of bacillus anthracis are never found in the blood of the 

 living animal. They are formed only when the blood comes 

 in contact with the outer atmosphere. They resist a 

 temperature of 95 C. for a short time only, and are certainly 

 killed at 100 C., hence the use of boiling water. 



!>355' It ls curious to observe, however, that spores of 

 bacillus anthracis which resist such adverse conditions are 

 killed by the simple agency of the direct rays of the sun. 

 M. Arloing has shown that the spores of bacillus anthracis 

 contained in the broth of the culture exposed to the sun are 



