16 



FARM ARITHMETIC. 



47. Whal; percentages of phosphoric acid, nitrogen 

 and potash are contained in the above f ertihzer ? 



48. When 400 pounds of this fertiHzer are used per 

 acre, how many pounds of phosphoric acid, nitrogen and 

 potash are added to the soil? 



Pounds of feraln per acre 1.000 2.000 3.000 4.00O 5.000 6.000 



1852-1871 < 



I672-IS8I' 



I8S2-I89I' 



1892-1901 



■ Manured every year. 



3 Manured every year until 1871,but no manure since that date. 



DNo manure since 1852. 



No Question About Value of Manure. 



A Widely Used Cotton Fertilizer. 



Acid phosphate, 900 pounds 



Cottonseed meal, . 800 pounds 



Kainit, 300 pounds 



49. What percentages of phosphoric acid, nitrogen 

 and potash are contained in above fertilizer? 



50. When 200 pounds are used per acre, how many 

 pounds of each element are added to the soil? 



