TIME AND TEMPERATURE 



193 



" The influence of time," Prof. Delepine adds, " is well shown by 

 the number of specimens remaining good, even at a high temperature, 

 when the milk had been kept only half a day. On the other hand, 

 the influence of temperature is still more, evident, for in every 

 category the number of good specimens is almost inversely propor- 

 tional to the height of the temperature. Still, it is important to keep 

 the two factors of time and temperature in mind. (What is produced 

 in a few hours in summer may also occur in winter, when the milk has 

 been kept a long time" ) j 



The converse is also true, namely, that fif the temperature of milk , 

 be reduced by refrigeration, the toxicity of the milk is lesseneo^/ 

 Professor Delepine has shown that the mortality from all causes in 

 guinea-pigs inoculated with refrigerated milk is considerably less 

 than it is if unrefrigerated milk be inoculated : 



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