304 



PHYSIOLOGY OF BACTERIA 



While all of this had been known for a long time, no 

 real understanding of the cause of death was obtained 

 until Paul (1909) started his quantitative investigations. 

 Though he used staphylococci which are likely to give 

 abnormal results (p. 296), he obtained a fair constancy 

 of the death-rate in his experiments. 



Paul dried the bacteria on small stones (garnets), of 

 uniform size (details, see Paul, Birstein and Reuss, 

 1910a), which were kept in test-tubes under varying 

 conditions. From time to time, some of them were 

 removed and shaken with sterile water to separate 

 the bacteria which were then counted by the plating 

 method. The first experiment of Paul, with dry 

 staphylococci at room temperature, at that of the 

 refrigerator, and at the temperature of liquid air, gave 

 the data of Table 87. 



