86 AGRICULTURE 



2. Observe the methods used on farms in your locality. Compare the 

 methods used by successful and Unsuccessful farmers. 



3. Put a layer of salt about one fourth of an inch thick in the bottom 

 of a pan and cover it with wet sand to the depth of two or three inches. 

 Set the pan in the sun till the sand is dry. What do you find on the sur- 

 face ? Put the top layer of sand in a glass of water ; let it settle, and taste 

 the water. Put similar layers of salt and sand in a pan having a bottom 

 of wire gauze over which is put a cloth. Pour water on this frequently 

 and allow it to drain off. Then dry the sand and compare with the other. 

 What do these experiments show as to the formation and reclamation 

 of alkali lands ? 



DRAINAGE 



Reclaiming Land by Drainage. Nothing is of more importance 

 to a crop than the regulation of soil moisture. If there be too little, 

 the plants perish for want of water; if too much, they starve for 

 lack of air to the roots. In low sections and in regions of heavy 

 rainfall, one of the chief problems is how to dispose of surplus 

 moisture. It is often necessary to drain these lands, that is, to 

 carry off the water by drains or ditches. 



Holland is a striking instance of the extensive and profitable 

 use of drainage. By dikes and ditches, thousands of acres have 

 been reclaimed from the sea. Their products every year are 

 worth millions of dollars. Our government has spent over ten 

 million dollars in dikes and jetties, to drain and protect the lower 

 Mississippi Valley. 



Farm Drainage. Farm drainage, which we are now consider- 

 ing, deals chiefly with the removal of free, or standing, water from 

 wet fields. In the eastern part of the United States, there are 

 over a hundred thousand square miles which need drainage. 

 These swamp and bottom lands are well supplied with plant food, 



