CAMPBELL'S SOIL CULTURE MANUAL 121 



take a narrow piece of ordinary newspaper, about one- 

 half inch wide, let it extend from the thumb and finger 

 about two inches, slowly move it down so the end of 

 the paper will come in contact with a single drop of water. 

 If you notice closely you will see a remarkable resistance 

 of the paper against the water. Very soon the little pores 

 begin to absorb the water, and the end of the paper be- 

 comes moist. Now slowly raise the paper and notice 

 how persistently the paper hangs to the water. When 

 it lets go there is a quick upward movement, thus show- 

 ing the power of attraction of water for water. Now 

 steadily move the fingers down slowly, watching the paper 

 and you will notice when it gets close to the water there 

 is a sudden movement down, even while there is a little 

 space between the moisture on the paper and the water 

 on the glass. The power of attraction is made very per- 

 ceptible by the quick connection of the two moist parti- 

 cles. Now draw the paper across the glass from one drop 

 to the other, you will notice the water all hangs together. 

 You will have a string or train of water two or three inches 

 long trailing on behind your paper. 



This illustrates how easy it is to get moisture into the 

 soil by keeping the surface constantly loose and open, so 

 that as the rain falls it soon works its way through the 

 larger pores until it reaches the moist particles in the firm 

 soil,' when it immediately percolates on down below. Here 

 again nature has done* a great deal for the semi-arid belt. 

 The peculiar formation and size of the usual particle of 

 soil is very favorable for percolation; also for its return 

 upward by capillary attraction to feed the plant during 

 our long dry seasons. 



Here again we must reiterate. When a heavy rain 

 comes, the effect is to mom or less dissolve the soil mulch 



