156 Report of the Acting Director and Chemist of the 



XV. Analyses of Commercial Fertilizers Collected during the 



Spring of 1895. 



SUMMAKY OF KESULTS. 



During the spring of 1895, there were collected 260 samples of 

 commercial fertilizers, representing 232 different brands. 



Of these 232 different brands, 221 contained nitrogen varying in 

 amount from 0,65 to 12.25 per cent. The average of all the 

 guarantee-analyses was 2.70 per cent, of nitrogen, while the average 

 amount found by the Station analysis was 2.79 per cent. 



There were 200 brands which contained available phosphoric acid, 

 varying in amount from 0.95 to 19.14 per cent. The average 

 amount of available phosphoric acid found by Station analysis ex- 

 ceeded the average guarantee-analyses by 0.62 per cent., the average 

 of all the guarantee-analyses being 7.97 per cent, and the average 

 actually found being 8.59 per cent. 



There were 205 brands which contained potash, varying from 0.53 

 to 32,44 per cent. The average amount of potash found by our 

 analysis exceeded the average guarantee-analysis by 0.45 per cent., 

 the average of all the guarantee -analyses being 4.90 per cent., and 

 the average actually found being 5.35 per cent. 



The retail price of the brands analyzed varied from $13 to $150 

 a ton and averaged $31.43. 



Of the 232 different brands collected, 136 were below the manu- 

 facturer's guarantee-analysis in one or more constitutents, in amounts 

 varying from 0.01 to 3,78 per cent. 



The amount of nitrogen was below the guarantee-analysis of the 

 manufacturer in 73 brands, the deficiency varying from 0.01 to 3,24 

 jDer cent, and averaging 0.36 per cent. In 44 of the 73 brands, the 

 deficiency was less than 0.25 per cent. ; in 10 brands, it was over 

 0.25 and below 0.50 per cent. ; in 11 brands, it was over 0.50 and 

 below 1 per cent. ; in 6 brands, the deficiency was over 1 and below 

 2 per cent. ; and in 2 brands, it was over 3 per cent. 



The amount of phosphoric acid was below the manufacturer's 

 guarantee-analysis in 56 brands, the deficiency varying from 0.06 to 

 3.78 per cent, and averaging 0.66 per cent. In 20 of the 56 brands, 

 the deficiency was less than 0.25 per cent. ; in 13 cases, it was above 



