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C. M. HILLIARD AND MILDRED A. DAVIS 



salt bath of a concentration to give approximately the tempera- 

 ture desired, and the temperature was watched for the period 

 of the experiment and adjusted when necessary. Melting of 

 frozen tubes was brought about gradually by immersion in cold 

 water. All plates were incubated at 37°C. and counted after 

 forty-two hours. 



To determine that the glucose in the concentrations used was 

 not germicidal, either on account of its chemical or osmotic 

 properties, each solution was inoculated and placed in the refrig- 

 erator at from 4 to 6°C. for three hours. At least four tests for 



each solution were made and the control in tap water was made 

 each time. The reductions in sugar solutions were variable 

 but were uniformly lower than those which occurred in water, so 

 we feel entirely justified in concluding that the sugar as such 

 had no germicidal influence. 



We then undertook to compare the effect of low temperatures 

 upon bacteria in a medium which crystallized, with one where 

 crystallization was absent. The detailed data are given for the 

 series of experiments at one temperature only and the average 

 reduction of a similar series of experiments at each of the other 

 temperatures is given in table 5. 



