J. W. Leather 241 



I have subjected the Piisa soil to the same treatment as that 

 employed by Russell and Appleyard. A portion of soil, which was 

 subsequently found to include 382-8 grams dry soil and 32-8 grams 

 water, was placed in a bottle and the air pumped out. It was then 

 left for four days connected with the Tiipler pump. At the end of the 

 first 24 hours a few c.c. of gas were obtained, after a further 24 hours 

 another small (juantity was removed, and on the fourth morning a much 

 less quantity was present. The total gas obtained measured 7-27 c.c. 

 and included carbon dioxide 5-62 c.c, oxygen O-IO c.c. The volume of 

 gas originally present in this soil would be about 100 c.c. 



In other two experiments the soil was taken in the special tool 

 which I have devised for the examination of soil gases. In this case 

 the gases are removed from the xmdisturhed soil. The volume of soil 

 was 1.54-4 c.c. in each case. In the first experiment 61-19 c.c. of gas 

 was removed at once. After standing for 48 hours 1 '87 c.c. of gas was 

 removed, of which 0-87 c.c. was carbon dioxide. In the second of these 

 experiments the gas first removed was .52-33 c.c. After standing for 

 48 hours, 2-80 c.c. more gas was obtained, of which 2-18 c.c. was carbon 

 dioxide. It is evident that this soil behaves differently from the 

 Rothamsted soil. The undisturbed soil yields after 48 hours a small 

 cpiantity of gas, most of which was probably present when the sample 

 was taken ; but the soil after disturbance yields a small amount of a 

 gas mixture which is cjualitatively similar to that obtained at Rotham- 

 sted, but is comparatively very small in cj[uantity. 



Soils will no doubt vary in respect of the amount of gases which 

 their solid constituents can condense, but I may here mention that the 

 soil of this part of India condenses so little that it is difficult to estimate 

 it; it is certainly less than 4 % of the whole of the gases present in 

 the soil. Details regarding this and other features of the soil gases 

 present in the land of this Institute are about to appear as a memoir. 



One is forced to the conclusion that the gas which was obtained on 

 successive days by Russell and Appleyard was formed and liberated 

 gradually, presumable by bacterial action. 



PnsA, 

 Wi June, 1915. 



