THE EARTH'S BOUNTY 



only enriches the soil with the nitrogen, phos- 

 phoric acid, and potash which it contains, but 

 it also renders the stored-up materials of the 

 soil more available, improves the mechanical 

 condition of the soil, makes it warmer, and en- 

 ables it to retain more moisture or to draw it 

 up from below. 



It should be clearly understood that when 

 the farmer sells meat, milk, grain, hay, vege- 

 tables, etc., from his farm, or neglects to save 

 and use the manure produced, he removes 

 from his soil a certain amount of potash, 

 phosphoric acid, and nitrogen that must be 

 restored sooner or later if productiveness is to 

 be maintained. 



The table on p. 129, compiled by Armsby, 

 shows the amount and value of fertilizing con- 

 stituents carried away from the soil in differ- 

 ent products. 



If the farmer, instead of selling off his 

 crops, feeds them to live stock on the farm as 

 far as possible, a large proportion of this fer- 

 tility, as shown above, is retained on the farm; 



128 



