162 Fertilizers 



Discussion of guarantees. 



It is shown in this table that, in order to convert am- 

 monia into its equivalent of nitrogen, the percentage 

 of ammonia should be multiplied by 82 per cent, or di- 

 vided by the factor 1.214, because ammonia is 82 per 

 cent nitrogen, and because one part of the nitrogen is 

 equivalent to 1.214 parts of ammonia. 



In order to determine the cost of a pound of ni- 

 trogen in dried blood, which is quoted., for example, 

 at $3 a "unit," 20 pounds of ammonia, the unit 

 20 pounds is multiplied by 82 per cent, which gives 

 16.40 as the pounds of nitrogen offered for $3, or 18.3 

 cents a pound. 



Bone phosphate of lime is, in round numbers, 46 

 per cent actual phosphoric acid. Hence, by multiply- 

 ing the bone phosphate by 46 per cent, the percent- 

 age of actual phosphoric acid is obtained. Ground 

 bone, for example, guaranteed to contain from 48 to 

 52 per cent bone phosphate, contains, in round num- 

 bers, 22 to 24 per cent of phosphoric acid. Sulfate 

 of potash is 54 per cent, and muriate of potash is 63 

 per cent "actual" or potassium oxide, respectively. 

 Hence, to convert the percentages of these forms into 

 their equivalents of "actual," they are multiplied by 

 the factors given. 



In such raw materials as nitrate of soda, muriate of 

 potash and sulfate of potash, a method of guaranteeing 

 is used which is based upon their purity as chemical salts. 

 That is, when pure they contain 100 per cent of the specific 

 salt, and the guarantee accompanying the commercial 

 product is simply a statement indicating their purity. 

 For example, when nitrate of soda is guaranteed to con- 



