52 CONSEEVATION OF THE SOIL 



(3) Since only 50% of the muriate of potash is potash, the 4 Ib. of 

 potash is 50% of the amount of muriate of potash required for the 

 mixture, or 8 Ib. of muriate of potash. 



(4) To the 71 ^lb. of nitrate of soda, phosphoric acid, and muriate 

 of potash must be added also 28 Ib. of sand or dry dirt, called filler, 

 to make the proper per cent. 



EXERCISE 



1. In a 125-pound sack of 2-10-2 fertilizer there are how 

 many pounds each of nitrogen, phosphoric acid, and potash ? 



2. In a ton of 4-8-4 fertilizer there are how many pounds 

 each of nitrogen, phosphoric acid, and potash ? 



3. Make 1 ton of wheat and corn 3-10-3 fertilizer from 

 nitrate of soda containing 15% of nitrogen, acid phosphate 

 containing 16% of phosphoric acidj and muriate of potash 

 containing 50% of potash. How much filler must be used ? 



4. From data given in paragraph 61, estimate the cost 

 of the material for making 1 ton of 4~8~4 potato fertilizer ; 

 1 ton of 2~5~8 tobacco fertilizer ; 1 ton of 2~8~7 potato 

 fertilizer ; 1 ton of 2-10-2 grain fertilizer. How much filler 

 is used with each ton ? 



5. Bring to school a number of labels taken from fertil- 

 izer sacks at home, and from the data previously given 

 estimate the cost of the material for making 1 ton. Find 

 the local dealer's price on each brand, and estimate the 

 saving on each ton by mixing it at home. 



6. Cottonseed meal that contains 5j% of nitrogen, 2% of 

 phosphoric acid, and 1^% of potash is worth how much per 

 ton if nitrogen is 20$ per pound, phosphoric acid 4$ per 

 pound, and potash 4$ per pound ? 



7. If a farmer puts 400 Ib. of fertilizer valued at $24 per 

 ton on 1 A. of corn, how many additional bushels of corn 

 worth 50$ per bushel must he raise to pay for the fertilizer ? 



