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G. S. WILSON 



PART II 



Comparison of the total and viable counts 



The primary object of this work was to make a comparison of 

 the total and viable counts, especially during the logarithmic 

 phase of growth, in order to ascertain if they were equal. From 

 a survey of previous work on the subject, one was led to expect 

 that all the bacilli would be found to be alive during this period. 

 To test this a series of 16 experiments was made. At the start 



Fig. 3. Showing the Total and Viable Counts ix a Broth Culture of 



Bact. suipestifer 



Total count = continuous line. Viable count = interrupted line 



comparative counts were conducted for the first 24 hours of 

 growth so as to obtain an idea of the general relations of the two 

 curves, but later on the counts were not continued beyond six to 

 nine hours, as by that time the logarithmic phase was already 

 past, and no object in following further progress was to be 

 achieved. 



To take one of the first experiments. The technique was as 

 follows: At 6 p.m., in the evening a tube of 5 cc. of broth was 

 inoculated with one loop of a culture of Bact. suipestifer, and in- 

 cubated at 23°C. overnight. At 9.20 a.m. the following morning, 

 after being warmed to 37°C., 10 drops of this culture were used 



