FERTILIZERS 35 



The muriate contains about 48% actual potash 

 and kainit about 12%. 



Bone phosphate must not be confused with phos- 

 phoric acid. The latter is derived from bone phos- 

 phate and is 45.8% of the bone phosphate; for 

 instance, 40% bone phosphate=18.32% phosphoric 

 acid. 



55. Allowance must be made for phosphoric acid 

 if it is derived from raw bone. It is then worth 

 about 2c. per pound, while if taken from steamed 

 bone would be worth fully 5c. per pound. In acidu- 

 lated goods the phosphoric acid is in three different 

 forms, with market values from 2c. up to 5%c. per 

 pound : the water-soluble being worth 5Msc. per 

 pound, the insoluble, 2c. per pound.* 



The source is just as important a consideration 

 as the quantity when considering the value. Both 

 the quantity of plant food (that is of nitrogen, 

 phosphoric acid and potash) and its source, which 

 determines its form, are really the only factors which 

 compose the value of a ton of fertilizers. (67) 



*No attempt is made to give market values. These fig- 

 ures are simply for comparison of the different forms of 

 phosphoric acid and are those usually used by State Agri- 

 cultural Stations. 



