SOIL HEAT 



321 



temperature, influenced, of course, by the conditions 

 already discussed. The effect of this heat supply is re- 

 flected in the seasonal, monthly, and daily soil tempera- 

 tures at the surface and at varying depths below. The 

 following data illustrate the differences that may ordi- 

 narily be expected to take place from season to season on 

 an average soil : — 



Average Temperature Readings Taken at Breslau, Ger- 

 many. 1 Average of Ten Years, 1901-1910 (in Degrees 

 Fahrenheit) 



Average Temperature Readings Taken at Lincoln, Ne- 

 braska. 2 Average of Twelve Years, 1890-1902 (in 

 Degrees Fahrenheit). 



Winter 

 Spring 

 Summer 

 Autumn 



Air 



25.9 

 49.9 

 73.8 

 53.9 



1 Inch 

 Deep 



28.8 

 54.8 

 83.0 

 56.4 



3 



Inches 

 Deep 



28.8 

 53.6 

 80.9 

 57.6 



Inches 

 Deep 



29.5 

 51.6 

 79.1 

 57.1 



12 

 Inches 

 Deep 



32.2 



48.5 

 73.8 

 57.5 



24 

 Inches 

 Deep 



36.3 

 45.7 

 69.0 

 59.3 



36 

 Inches 

 Deep 



39.1 

 44.3 

 66.2 

 60.3 



1 Schulze, B., and Burmester, H. Beobochtungen tiber 

 Temperaturverhaltnisse der Bodenoberflache und verschiedener 

 Bodentiefen. Internat. Mitt, fur Bodenkunde, Band II, Heft 

 2-3, Seite 133-148. 1912. 



2 Swezey, G. D. Soil Temperatures at Lincoln, Nebraska. 

 Nebraska Agr. Exp. Sta., 16th Ann. Rept. r pp. 95-102. 1903. 



