TILE DRAINAGE. 



or snows that soak the soil into mud, filling all its pores full, 

 and standing stagnant on or in the soil. In spring and sum- 

 mer it stands in depressions until it evaporates. In fall and 

 winter it stands and freezes and thaws. In either case it 

 injures or perhaps ruins the crops. Thousands of acres of 

 wheat in Ohio and other States during the past wet winter 

 (1890-91) have been killed thus by too much cold water ; and 

 the epitaph might be, " Died of wet feet. 7 ' " Seeing is be- 

 lieving," and I have seen it from car-windows for hundreds 

 of miles, the dry knolls and slopes having good wheat ; the 

 wet depressions or flat surfaces having little or none. Nor 

 does water have to stand upon the surface to kill or greatly 



ODE F 



FIG. 2 



-Capillary attraction in small tubes. The smaller the tube 

 the higher the water rises in it. 



Fig. 2. Capillary attraction between divergent surfaces of glass for 

 example opened like the cover of a book. 



damage the crops. If it stands stagnant in the soil, saturat- 

 ing it, that is, soaking all the pores completely full, it does 

 almost equal damage ; for the roots of our agricultural 

 plants need air as well as moisture, and must have it. If 

 long deprived of it they dwindle or even die. The moisture 



