• The Composition and Use of Fertilizers. 315 



how different materials may be put together to make up a given 

 formula. 



Suppose that we desire to make one ton of a mixture contain- 

 ing — 



Per cent. 



Nitrogen 4 



Available phosphoric acid 8 



Potash 10 



Suppose, in addition, that we have on hand for our purpose the 



following materials: 



Nitrate of soda containing 16 per cent, of nitrogen. 



Acid phosphate containing 15 per cent, of available phosphoric 

 acid. 



Muriate of potash containing 50 per cent, of actual potash. 



How many pounds of each of these materials shall we take to 

 make one ton of a mixture having the composition given above? 



To contain four per cent, of nitrogen, the ton must contain 80 

 pounds. The material which we use contains 16 pounds of nitro- 

 gen in 100 pounds, and hence 500 pounds of nitrate of soda would 

 be required to furnish 80 pounds of nitrogen. 



To contain eight per cent, of available phosphoric acid, the ton 

 must contain 160 pounds. Our material contains in 100 pounds 

 15 pounds of available phosphoric acid and hence 1,067 pounds 

 of acid phosphate would be required to furnish 160 pounds of 

 available phosphoric acid. 



To contain 10 per cent, of actual potash, the ton must contain 

 200 pounds. Our muriate of potash is one-half actual potash, and 

 hence 400 pounds of muriate would be required to furnish 200 

 pounds of actual potash. 



We should, then, have the following amounts of materials to be 

 used for one ton of fertilizer: 

 500 pounds nitrate of soda. 



1,067 pounds acid phosphate. 

 400 pounds muriate or potash. 



1,967 pounds of these mixed materials furnish the amounts of 

 nitrogen, potash and phosphoric acid we need for one ton of our 

 formula. How shall we make the mixture up to one ton ? We 



