374 DRY FARMING 



as individuals might with profit give more attention to 

 mathematics in ..relation to our business. Our profits are 

 determined by the difference between our receipts and 

 our expenditures, and not by our gross incomes. Let us 

 know, if possible, the essentials of our own business enter- 

 prises. It would seem also that we as a class must prac- 

 tise greater co-operation. Our co-operative enterprises 

 have accomplished much in the interest of the farmer, 

 chiefly in the marketing end of his business, and they 

 have still much opportunity for service. At the same 

 time let us not forget that as individuals we can still do 

 much to lower the cost of production and to lessen the 

 risk in farming, both of which are directly related to 

 profit. 



337. Legumes and Inoculation. The air over every 

 acre of land contains seventy million pounds of nitrogen, 

 the most costly of fertilizing elements. This amount is 

 sufficient to supply the nitrogen of fifty bushel crops of 

 wheat every year for a million years, yet farmers in some 

 countries are paying twenty cents a pound for nitrogen 

 to put on the land. Nitrogen in the air can be secured 

 at no cost to the farmer if he will but grow some legume 

 crop at intervals. This kind of crop when inoculated 

 with nitrogen-fixing bacteria, has the power of drawing 

 upon the immense store of nitrogen in the air. 



In such of our virgin soils as are rich in nitrogen it is 

 possible that the use of legume crops may not now result 

 in large increases in yield. Investigations at present 

 under way will soon answer that question. In the mean- 

 time the fundamental fact regarding legumes should not 

 be forgotten. Neither should it be forgotten that all our 

 soils are not virgin, nor are all rich in nitrogen. 



