42 



BOARD OF AGRICULTURE. 



[Jan. 



of a 28-inch rainfall. American trials have given the fol- 

 lowing figures as calculated for the Waushakum Farm lysi- 

 meter at South Framingham, Mass., from 1876 to 1878, 

 inclusive : — 



The figures derived from the New York Agricultural Experi- 

 ment Station lysimeters,* from Aug. 1, 1882, to Nov. 1, 1887, 

 inclusive, show an average evaporation of 73.4 per cent of 

 the 23.724 inches of rainfall, being 85.4 per cent from sod, 

 70.7 per cent fi'om bare soil, and 63.9 per cent from culti- 

 vated soil. The average for June, July, August and Sep- 

 tember, growing months, was 84.04 per cent of the 11.84 

 inch rainfall. 



From a few districts we have careful estimates of the 

 evaporation which takes place from large areas under natural 

 conditions, and such have been gathered together by Dr. S. 

 M. Babcock,f as follows : — 



As Croton River flows mainly through a sparsely settled 

 region, and the other watersheds are in a populous and 



* Report of N. Y. Ag. Ex. Sta. for 1887, p. 397. 

 t Report N. Y. Ag. Ex. Sta. for 1887, p. 389, et seq. 



