57 



ried .346 to 2.611 percent. Similar experiments were 

 made by Fleck 1 who found the percentages of carbon 

 dioxide at 2, 4 and 6 meters in a soil without plant 

 cover to be 1.68, 2.75 and 3.38 respectively. The 

 corresponding percentages of oxygen were 18.9, 17.3 

 and 16.7. In soil with plant cover the conditions were 

 reversed and the largest percentages of carbon dioxide 

 were found in the upper layers of the soil. The experi- 

 ments of Salger 2 led to results essentially similar and 

 showed that the drawing of air from the soil for a day 

 preparatory to taking the sample lowered the carbon 

 dioxide content considerably in the case of air drawn 

 from 1.5 m. but only slightly in the case of air from 

 3.0 m. Salger obtained carbon dioxide contents, without 

 prior ventilation, of .39 to 1.53 percent, the high 

 values being due, probably, to the proxemity of a 

 refuse-pit. Experiments of Fodor gave extreme values 

 for carbon dioxide of .899 and 1.059 percent in air 

 from 1 m. and 2.631 and 5.445 percent in air from 4 m. 

 The corresponding oxygen values were 18.797 and 21.335 

 percent for 1 m. and 17.2y0 and 18.532 percent for 3 

 meters. 



Tl Jahresber. Agr.-Chem. 16: 159 ( ). 



2. Diss., Erlangen, 1880. 



3. Boden und ,7asser, pp. 99-142 (1882). 



