416 



REPORT OF THE COMMISSIONERS OF 



Rothamsted Agricultural Experiment Station and at other places for a number of 

 years.* We may cite some of the results obtained by Mr. Graves, and detailed in his 

 paper On Evaporation and on Percolation before the Institution of Civil Engineers, 

 Volume XLV. The following summary of results for fourteen years, all in inches, 

 includes the rainfall and percolation through turfed soil and through a bed of deep, 

 fine sand, the soil and sand being contained in a strong, open topped, water-tight, 

 slate box or tank, with an area of one square yard and thirty-six inches in depth. The 

 soil is turfed over and the grass occasionally cut. 















RAINFALL 



PERCOLATION 



EVAPORATION 



YEAR 

















GROUND 



SAND 



GROUND 



SAND 



WATER 



i860, 



3 2 -5 6 



IO.76 



24.36 



2 I.80 



9.IO 



21.06 



l86l, 









. 



23- 6 3 



5-7 1 



16.36 



I7.92 



7.27 



25.OI 



1862, 











26.58 



8-55 



2I.I8 



lS.03 



5-40 



H-33 



1863, 













19.77 



3-7 6 



16.4I 



16.OI 



3-3 6 



18.27 



1864, 













15.89 



3.82 



12.64 



12.07 



3- 2 5 



18.64 



1865, 













29.25 



11. 15 



27.82 



18.10 



i-43 



20.12 



1866, 













31-7° 



12.59 



28.II 



19. 1 I 



3-59 



18.82 



1867, 













27.44 



5.16 



22.42 



22.28 



5.02 



20.06 



1868, 













23-3 1 



7. 11 



20.20 



l6.20 



3- 11 



26.93 



1869, 













24.56 



8.05 



22.14 



16.5I 



2.42 



19.06 



187O, 













20.40 



7- 2 3 



18.7O 



I3-I7 



1.70 



20.40 



187I, 













24.08 



6.19 



20.08 



I7.89 



4.00 



19.58 



1872, 













37-17 



12.03 



3°-05 



2 5- x 4 



7.12 



22.92 



1873, 













2 3-77 



4-°5 



20.I 2 



19.72 



3- 6 5 



20.40 



Me£ 



m, 



25.72 



7-58 



21.41 



18.14 



4-3i 



20. 6l 



EXPERIMENTS AT GENEVA. 



Experiments at the New York State Agricultural Experiment Station at Geneva 

 may also be referred to. In August, 1882, the Geneva Agricultural Experiment Station 

 began a set of observations on the amount of percolation through three drain gages, 

 gage No. I being covered with sod, with the grass kept short by frequent cuttings; 

 gage No. 2 was kept free from all vegetation, its surface being left undisturbed, while 

 the surface of No. 3 was kept in a loose and fine condition by frequent stirrings with 

 a trowel. These experiments were continued from 1882 until iSgo.f 



* Extended references to these data may be found in the author's Report on the Upper Hudson 

 Storage Surveys for 1896. 



t For full detail see the Annual Reports of the New York Agricultural Experiment Station at 

 Geneva from the Second (1883) to the Ninth (1890). 



