PLANT FEEDING. 15 



We now have — 



Phosphoric acid Nitrogen Potash 



In acid phosphate 168 00 



In cottonseed meal 10 28 6 



In kainit 00 00 50 



178 28 56 



« 



42. In a ton of fertilizer mixed in this way what is the 



percentage of each element of plant food? 



Solution : To find this percentage divide the amount of each 



element by the total amount of the mixtuie, and multiply by 100. 



The calculation is as follows : ^ 



Per cent. 



Z.i 



2.000 X 100 = 8.9 

 2.000 X 100 = 1.4 

 2,000 X 100 = 2.8 



Phosphoric acid, 17 



Nitrogen, 2 



Potash, 56 



Note.— This would be designated as a 8.9-1.4-2.8 mixture. 



43. How many pounds of nitrogen, phosphoric acid 

 and potash in a ton of fertilizer, containing 1 .400 pounds 

 of acid phosphate, 100 pounds of nitrate of soda, 200 

 pounds of cottonseed meal. 100 pounds of dried blood, 

 and 200 pounds of muriate of potash ? 



44. What is the percentage of phosphoric acid, nitro- 

 gen and potash in the above fertilizer? 



45. Suppose, instead of using 1.400 pounds of acid 

 phosphate, we use 1.400 pounds of ground bone: how 

 many pounds of nitrogen, phosphoric acid, and potash 

 will the ton of mixture contain ? 



46. What is the percentage of phosphoric acid, nitro- 

 gen and potash in a ton of the mixture ? 



Fertilizer formulae: 



A Widely Used Corn Fertiliser. 

 Add phosphate, 875 pounds 



Cottonseed meal, 950 pounds 



Kainit. 175 pounds 



Total, 2,000 pounds 



