Water is made up of hydrogen and oxygen. Sugar, glu- 

 cose, starch, fiber and oil are made up of carbon, hydrogen and 

 oxygen, and about eighty-five per cent, of the albuminoids is 

 made up of the same three elements, while the remaining fifteen 

 per cent, is nitrogen. It has been shown by various experiments 

 that all the carbon of a plant comes from a gas called " carbon- 

 ic acid gas " which exists in the air; the hydrogen and oxygen 

 come chiefly from water. 



Nitrogen is believed to come almost wholly from the soil, 

 and the ash also comes wholly from the soil. Thus it appears 

 that the elements from which the 12.51 ounces of starch, sugar, 

 fiber, oil, etc., were constructed came from the air and water ; 

 add to this eighty-five per cent, of the albuminoids and we get 

 13.79 ounces, which with the 65.15 ounces of water gives us sev- 

 enty-nine ounces out of the eighty ounces total weight of the 

 stalk, which came from the carbonic acid of the air, and from 

 the water of the soil ; this water also comes from the air. The 

 remaining ounce is made up of eighty-eight hundredths of an 

 ounce of ash and twelve hundredths of an ounce of nitrogen. 

 With this ounce the study of feeding plants commences, for na- 

 ture provides the other seventy-nine ounces free. 



The figures will be more valuable if we apply them to the pro- 

 duct of an acre of land rather than to a single stalk. 



The yield was twenty tons, or 40,000 pounds, of corn as it 

 was cut for the silo. This amount contained the following : 



o 



Taken from Taken from the 

 soil, lbs. air and water, lbs. 



Water, 32,580 



Aiu • -I ( Nitrogen, 112 



Albummoids, W- 1 1 i j 



C7c6 lbs) 1 Cardon, hydrogen and 

 ^'•^ ( cygen. 



Fat, 



Cane sugar, 

 Carbo- j Glucose, 

 hydrates, ] Starch, 



[ Fiber, 

 Ash, 408 



521 



40,000 



