62 



o. rsHii 



In my observations on the effect of temperature of the agglu- 

 tination with Bad. typhosum, Bad. paraty-phosum A and B, 

 Bad. coli, and the dysentery group, the tubes kept in a water 

 bath for two hours at 45°C., showed a slightly weaker reaction than 

 those kept at room temperature or 37°C., while at 55°C., the 

 reaction was much weaker than at 45°C. The results, after 

 leaving the tubes for 2 to 3 hours, or even for twenty-four hours at 

 room temperature, were just the same as they were when the 

 tubes were placed in the water bath at 37°C. for two to three 

 hours and then left standing at room temperature over night. 



TABLE 12 

 Agglulinalion tests conducted with bacilli after heating at 55°C.for two hours 



Kejj: 5, complete; 4, almost complete; 3, weak; 2, very weak; 0, negative 

 agglutination. 



In the next experiments (table 12), bacilli were heated at 

 55°C. for two hours before conducting the agglutination test; 

 it became evident that these bacilU had less agglutinating power 

 than the unheated bacilli. On the other hand, the serum which 

 had been heated at 55°C. for two hours gave just the same re- 

 sults as serum which had not been heated. 



When temperatures from 45°C. to 55°C. were used, the clumps 

 were smaller than when the test was conducted at room tempera- 

 ture or 37°C. This was true when either the microscopic or 

 macroscopic methods were employed. 



The latter temperature is therefore to be preferred, ^ith the 

 colon-typhoid group with or without formalin; the end results, 

 in relation to the temperature, are just the same. 



