62 



Elementary Principles of Agriculture 



95b. Rate of Rise of Water Through Soils of Different Texture. 

 For this test, a number of ordinary lamp chimneys serve very well, 

 because the results may be easily observed. These may be secured at 

 stores. Select three samples of soil: one sand, one clay, and one a soil 

 with much humus. Prepare two chimneys of each kind of soil, as fol- 

 lows: Close the tops of the chimneys with muslin. In number one, 

 let the soil particles drop lightly into the chimney and remain very 

 loose. In number two, pour in a little at a time and press slightly 



with a stick. Do not 

 try to make too com- 

 pact, lest the chim- 

 ney be broken. Put 

 all the chimneys in a 

 vessel of water, as 

 shown in Fig. 37, 

 and note the rise of 

 the moisture every 

 recess hour. 



What effect does 

 compacting the soils 

 have on the quick- 

 ness with which they 

 absorb water in sand? 

 In clay? In humus? 

 Would the water 

 percolate down through these soils in the same way; and rate? 

 Try it. 



95c. Effect of Mulches on Evaporation of Water from Soils. 

 Secure seven or eight three-pound tomato cans from which the 

 tops have been melted carefully off to leave smooth rims. Fill 



Fig. 37. To test the rise of water through soils of 

 different texture. 



