And so with the terms bone phosphate and phos- 

 phoric acid. The phosphoric acid comes from the 

 bone phosphate. For example, it takes 30% of bone 

 phosphate (sometimes called "bone phosphate of 

 lime") to make 13.74% of phosphoric acid. When 

 both terms are employed by the manufacturer the 

 words, "equal to" should be used, thus: "Bone 

 phosphate of lime, 30%, equal to phosphoric acid, 

 13.74%," which means that the manufacturer used 

 600 pounds of bone phosphate or bone 30% of the 

 ton to obtain 13.74% of phosphoric acid. 



Multiply the percentage of bone phosphate by 

 .458 and the result will be the equivalent in phos- 

 phoric acid, thus: 30% bone phosphate of lime 

 X. 458=13.74% phosphoric acid. 



In estimating the value of a ton in dollars and 

 cents, phosphoric acid from fine bone is worth about 

 5Y2 cents per pound, while its equivalent in terms of 

 bone phosphate is worth only 2^ cents per pound. 

 Only one should be included in the estimate. 



Where the "soluble," the "reverted," and the 

 "insoluble," and the "total" phosphoric acid are all 

 given, it is understood that the "total" is made up 

 of the first three mentioned. 



The sulphate and muriate of potash will analyze 

 in round numbers about 50% actual potash (some- 

 times expressed as KaO). In other words, it takes 

 two pounds of sulphate or muriate of potash to 



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