No. 6. 



DEPARTMENT OF AGRICULTURE, 



321 



The valuable results from the use of lime seem to diepend partly on 

 the fact that it stimulates the development of soil bacteria. This was 

 shown in certain pot experiments conducted by the writer. 



Pots were tilled with soil to which was added an equal quantity of 

 clean gray stream sand. 



To pots one and two nothing was added. 



To pots three and four was added lime at the rate of 1,000 lbs. per 

 acre. 



To pots five and six was added lime at the rate of 2,000 lbs. per 

 acre. 



To pots seven and eight was added lime at the rate of 4,000 lbs. per 

 acre. 



The number of bacteria per dry gram of soil in each pot was de- 

 termined at the beginning of the experiment, and again seven weeks 

 later. 



The results are shown in the following table: 



Table III. 



1 Nothing, 



2 Nothing 



3 1,000 lbs. lime, 



4 1,000 lbs. lime, 



5 2,000 lbs. lime, 

 g 2,000 lbs. lime, 



7 4,000 lbs. lime, 



8 4,000 lbs. lime. 



441,000 



567,000 

 734.000 

 703,000 

 908,000 

 406. 000 

 457,000 

 504, 000 



440,000 

 395,000 

 1,026,000 

 2,076.000 

 1,325,000 

 1,319,000 

 4,481.005 

 6,662,000 



The preceding experiment has been repeated with the same result, 

 sufficient to demonstrate the value of lime, at least in the type of 

 soils under consideration, in increasing the number of bacteria 

 therein. 



21—6—1902 



