60 BOARD OF AGRICULTURE. [Jan., 



AFTERNOON SESSION. 



The meeting was called to order at 2 o'clock, by Vice-Presi- 

 dent Hyde, who introduced Dr. Edward H. Jenkins of New 

 Haven. 



COMMERCIAL FERTILIZERS, SOURCES OF SUPPLY 

 AND HISTORY OP THE TRADE. 



BY DR. E. H. JENKINS, NEW HAVEN, CONN. 



Mr. President and Gentlemen: — At the suggestion of the Secre- 

 tary of the Board I am to speak of the Sources of Supply of 

 Commercial Fertihzers and the History of the Trade in them. 

 The ordinary manure of the farm and various waste products 

 which are sold at a low price, and often act rather as amendments 

 than as fertilizers,^ do not come under discussion here. They may 

 in some cases be more valuable to the farmer than any other 

 application; they have a history as old as the art of agriculture 

 and to some extent a commercial value, but the term Commercial 

 Fertilizers is now limited to those articles occurring as natural 

 deposits, like guano and Chili saltpeter; or manipulated in some 

 way, like dried blood and fish scrap; or regularly manufactured, 

 like superphosphates and potash salts, which are powerful fertiliz- 

 ers, are expensive in comparison with farm manure, and are regu- 

 larly quoted in our market report. 



The history of the trade in such materials dates back not more 

 than about forty years. Not much earlier than that was the need 

 of them appreciated and a demand created, of sufficient proportions 

 to establish a trade. But, though no very extensive use was made 

 of them prior to that time, the value of bone, fish, and even of super- 

 phosphate of lime was here and there recognized long ago in farm 

 practice. The first settlers in this country learned of the aborigi- 

 nes on the coast that a fish planted in each hill of maize greatly 

 increased the crop, bones were used as manure in England to some 

 extent early in tliis century, and superphosphate of Hme was made and 

 applied by Sir James Murray in England as early as 1817. 



In 1840, ;9,ppeared a work by Justus Von Liebig, on Chemistry in 

 its Relations to Physiology and Agriculture, a book which was of 

 inestimable service, for it showed for the first time where the founda- 

 tion of agriculture as a science was to be laid, it opened the way for 



