128 



EXPERIMENT STATION. 



[Jan. 



normal acid in all the cxix'riinents. In the third series of ex- 

 periments, where inoculation was made with Bacillus subtilis, 

 the following method was used. A j)ui'c tuhe culture of J^acillus 

 subtilis was made ; from this pure culture a nundjer of bacteria 

 were transferred with a platinum loop to 100 cubic centimeters 

 of sterilized water. From here on the method was followed as 

 above indicated. 



Experimental. 

 Table II. — Showing Comparison of the A'lonber of Bacteria in Decoctions 

 of Sterilized and Unsterilized Loam. {Inoculations made with Ordinary 

 Soil Bacteria.) 



The results shown in Table II. are of special interest for the 

 following reason : in the three experiments recorded in this table 

 the sterilized loam decoctions were found to contain a far greater 

 number of bacteria per cubic centimeter of contents than the 

 unsterilized loam decoction. 



Table III. — Showing Comparison between the Number of Bacteria in 

 Decoctions of Sterilized and Unsterilized Loam and Subsoil. {Inocu- 

 lations made with Ordinary Soil Bacteria.) 



Soil. 



Sterilized loam, 

 Unsterilized loam, . 

 Sterilized subsoil, 

 Unsterilized subsoil, 



Number of Bacteria in 1 Cubic Centi- 

 meter OF Decoction. 



Experiment 1. Experiment 2. Average 



5.724,000 



203,520 



76,320 



178,080 



4,693,060 

 199,308 

 81,134 

 185,138 



5,208,530 



201,414 



78,726 



181,608 



The results given in Table III. are important since thev show 

 that decoctions made from different soils affect the growth of 

 bacteria in them in a decidedly different manner. When a ster- 

 ilized loam is used we find a greater number of bacteria present 



