190 RETORT OF THE DEPARTMENT OF BACTERIOLOGY OF THE 



BACTERIA 1<)13 



NOV. DEC. 



MOISTURE 



40 



FROZCN FROZCN 



TEMPERATURE 

 15° 



10" 



5° 



0* 

 -5* 

 HOT 

 -15° 



Graph VII. — Bacterial Counts in Unaerated Soil, Pot Experiment, 



1913-14. 

 Bacteria in millions per gram; moisture content in percentage, dry basis; 

 temperature in degrees Centigrade, average per week. 



