336 BOARD OF AGRICULTURE. 



ing constituents; for on that particular circumstance depends 

 the decision where and how to turn the various articles to the 

 most economical account. A classification more prominently- 

 based on their relative proportion of nitrogen and phosphoric 

 acid, with simpler names for each class, would be both 

 rational and suggestive. That course once adopted would 

 enable us to assign to the various kinds of guano their 

 proper position among our commercial nitrogenous phos- 

 phates, which could not fail to turn a more general attention 

 to their respective special fitness for the production of a 

 variety of crops. The variable character of the Peruvian 

 guano of the present day favors the adoption of the princi- 

 ples of classification previously advocated. To establish 

 three standards corresponding approximately to those no- 

 ticeable with reference to the general character of the nitro- 

 genous phosphates and superphosphates, i.e., one nitrogen 

 to one phosphoric acid, one nitrogen to two or three phos- 

 phoric acid, one nitrogen to four or five phosphoric acid, 

 and to maintain them for years, by mixing different cargoes 

 to suit the adopted scale, whatever that may be, seems, for 

 several important reasons, deserving a careful consideration 

 on the part of the importers of the Peruvian guano. The 

 extensive application of some of our standard superphos- 

 phates is, to say the least, as much due to the maintaining of a 

 general uniform character during past years as to their pecul- 

 iar chemical composition. Farmers have learned how, where, 

 and to what extent, to use them to secure paying returns. 



The following copy of a recent statement regarding the 

 changes in the consumption of the Raiv Genuine Peruvian 

 Guano, and of the Ohlendorf Standard Soluble Peruvian 

 Guano, described in some of my previous reports, in the 

 Province Saxony of Prussia, during the years from 1866 to 

 1872, may be, for several reasons, not without interest in this 

 connection. 



Raw Peru. Guano. Ohlendorf Sol. Peru. Guano. 

 Tons (2,000 lbs.). Tons (2,000 lbs.). 



1866 3,331 4,115 



1869 1,713 12,292 



1872 216 21,522 



Ohlendorf's Soluble Guano corresponds with the Rectified 

 Peruvian Guano of our dealers, as far as their general 

 character is concerned. 



