No. 7. 



DEPARTMENT OF AGRICULTURE. 



673 



for soluble and reverted phosphoric acid have not been given sepa- 

 rately, but are combined into a single guaranty for available phos- 

 phoric acid; in cases where the maker's guaranty does not 

 specifically mention available phosphoric acid, the sum of the lowest 

 figures given by him for soluble and reverted phosphoric acid is used. 

 The law of 1879 allowed the maker to express his guaranty for nitro- 

 gen either in terms of that element or in terms of the ammonia 

 equivalent thereto; since ammonia is composed of three parts of 

 hydrogen and fourteen parts of nitrogen, it is a very simple matter 

 to calculate the amount of one, when the amount of the other is 

 given; the amount of nitrogen multiplied by 1.214 will give the 

 corresponding amount of ammonia, and the amount of ammonia 

 multiplied by 0.824 will give the corresponding amount of nitrogen. 

 In these tables, the expression is in terms of nitrogen. 



The law of 1901 abolishes this alternative and requires that the 

 guaranty shall be given in terms of nitrogen. Many manufacturers 

 after complying with the terms of the law, insert additional items 

 in their guaranties, often with the result of misleading or confusing 

 the buyer; the latter will do well to give heed to those items only 

 that are given as the law requires and that are presented in these 

 tables. 



A summary of the analyses made this season may be presented as 

 follows: 



Summary of Analyses Made This Season. 



c 



o 



£1 



•C 



c 



3 



o 



The cases of departure of goods from their guaranteed composi- 

 tion observed this season, including only those cases in which it 

 amounted to two-tenths per cent, or more, were as follows: 



43—7—1908. 



