Keport of Chemist of AgkiculturIl Experiment Station. 139 



aboye 1 and below 2 per cent; in 2 brands it was above 2 and 

 below 3 per cent; in 2 brands it was above 3 and below 4 per 

 cent; and in 2 brands it was above 4 and below 5 per cent. 



The amount of potash was below the manufacturer's guarantee- 

 analysis in 57 different brands, the deficiency varying from 0.04 

 to 2.91 per cent and averaging 0.56 per cent. In 21 of the 57 

 brands the deficiency was below 0.25 per cent; in 13 brands it 

 was above 0.25 and below 0.50 per cent; in 13 brands it was 

 above 0.50 and below 1 per cent; in 9 brands the deficiency was 

 above 1 and below 2 per cent; and in 1 brand it was above 2 

 and below 3 per cent. 



The retail selling price of the brands collected varied from 

 $6 to |65 a ton and averaged |28.96. The retail cost of the sepa- 

 rate ingredients unmixed was |23.37 or |5.59 less than the selling 

 price. 



INTRODUCTION. 



1. Explanation of Terms used in Stating Results of Chemical 



Analysis of Fertilizers. 



In the tables which give the results of our analysis of ferti- 

 lizers the following terms are used to express the results : 

 Nitrogen. 



j Total. 

 Phosphoric Acid '. 



( Available. 



Potash, soluble In icuter. 



We give a brief explanation of these terms as used in our 

 tables of analysis. 



(i) Nitrogen. — The figures in the column headed *' Nitrogen " 

 state the number of pounds of the element nitrogen present in 

 one hundred pounds of fertilizer. This form of statement does 

 not distinguish the source from which the nitrogen comes, but 

 simply states the total amount of nitrogen without regard to the 

 form or forms in which it may be present. 



(2) Phosphoric Acid. — There are usually present in fertilizers 

 three different forms of phosphoric acid compounds knows as (1) 

 " Soluble," (2) " Reverted," and (3) " Insoluble." All these dif- 

 ferent forms, taken together, are called "Total" phosphoric acid. 

 The soluble and reverted forms taken together are called "Avail- 

 able," because both of these forms can more or less readily be 

 used by plants. 



