Photograph from U. S. Department of Agriculture 



THE "BADENTA" TAKING OX A CARGO OF WHEAT FROM A BALTIMORE ELEVATOR 



The long pipes extending from the elevator to the ship carry the wheat by gravity from 

 its bins to the hold of the ship. In unloading, the grain is carried out of the ship by steam- 

 driven endless belts of buckets. In 1913 the United States supplied the outside world with 

 92,000,000 bushels of wheat, 12,000,000 bushels of flour, 17,000,000 bushels of barley, and other 

 breadstuffs in proportion. 



the era of commercial fertilizer. Before 

 his discoveries were made, man had only 

 an empiric control over the productivity 

 of his land. He could only sow the seed 

 and then trust to Providence for his har- 

 vest. 



And he knew that every harvest saw 

 his land less productive, for each crop 

 drew its draft upon the bank of the soil 

 and cut down the account of fertility just 

 that much. It was a case of always draw- 

 ing out and never putting in, and even 

 nature's deposits must ultimately be ex- 

 hausted under such a procedure. The 

 result was that it began to appear that 

 the agricultural machine would outlive its 

 day, since soil exhaustion appeared in- 

 evitable and world hunger an unavertible 

 calamity. 



EXHAUSTION OF THE SOIL NEEDLESS 



But when Liebig discovered that nitro- 

 gen, phosphorus, and potash are the only 

 three indispensible articles in the menu of 

 the plant, and that if it is given these it 

 can thrive year after year and generation 

 after generation on the same soil without 

 impoverishing it, he laid the foundation 

 of the new science of soil fertility — a 

 science that permits man, through the use 

 of proper fertilizers, to go on and on in 

 developing and improving his ground. 



Who that is a student of farming has 

 not seen a run-down farm on one side of 

 a line fence and a highly productive one 

 on the other. I have known land to have 

 its per -acre production of wheat in- 

 creased threefold and its production of 



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