EXERCISE A-27. TO STUDY THE WATER LOSS FROM 

 CULTIVATED, UNCULTIVATED AND MULCHED SOIL 

 SURFACES. 



Equipment: Three galvanized-iron cylinders; shallow 

 Dan; table knife; a pair of scales having a capacity of fifty 



pounds; a small quantity of cut straw; 

 a quantity of dry, sifted loam soil. 



Method: Number the three cylin- 

 ders and fill each to within one inch 

 of the top with the dry soil. Pour 

 water into the jacket at the bottom 

 until the soil appears moist at the 

 surface. This will probably require 

 several hours, but the experiment will 

 need no attention during this time 

 except to see that the water is re- 

 plenished in the jackets from time to 

 time. It is a good plan to start the 

 exercise in the afternoon and allow 

 the cylinders to stand over night or 

 until the next period. 

 After the water has reached the surface of the soil in 

 all of the cylinders they should receive the following treat- 

 ment : 



No. 1. Compact the surface. 



56 



Fig. 24. — Galvanized 

 Iron Mulch Cylinder. 



