110 Agricultural Experiment Station, Ithaca, N. Y. 



the two media has upon the relation of root pressure to transpiration. 

 At the lower benches (those at the side of the house where the glass is 

 quite close to the beds) the soil, from a few observations, possessed a 

 temperature of 2° to 5° Fahr. lower than the air, while in the center of 



Tablk of Comparative Soil and Air Temperatures (Fahrenheit). 



the house where there was an opportunity for the warm air to rise 

 toward the ridge, the difference in soil and air temperature was greater, 

 being more marked the higher the elevation at which the temj^erature 

 was taken in the air. 



