54 



CHEMICAL FERTILIZERS; AND LIME 



Table for calculating raw fertilizer material required per ton by mixtures of 

 given composition. Continued 



To mix a 2-8-6 fertilizer, i.e. a fertilizer containing 2 per cent 

 nitrogen, 8 per cent phosphoric acid and 6 per cent potash, the 

 quantities of raw material may be calculated as follows : 



2 X 133 = 266 Ib. nitrate of soda 

 8 X 143 = 1144 Ib. acid phosphate 

 6 X 40 = 240 Ib. muriate of potash 

 1650 Ib. mixture 



If dried blood were used instead of nitrate of soda, it would be 

 necessary to use 322 Ib. of it to secure the required amount of nitro- 

 gen (2 x 161 = 322) in the ton. If the formula called for ammonia 

 rather than nitrogen, the multiple would be 110 or 133 respectively. 



Soil Analysis and Fertilizer Tests (Cavanaugh) 



A chemical analysis of a soil consists in finding the amounts of nitrogen, 

 phosphoric acid, potash, lime, magnesia, and humus that it contains. 

 It may be carried further, and the other constituents determined. 

 These materials, except the humus and nitrogen, are extracted from 

 the soil by strong acids. The action of these acids is many times 

 stronger than is ever brought to bear on the soil in its normal con- 



