1891.] PUBLIC DOCUMENT — No. 33. 233 



Sulphate of ammonia, Dry ground fish, 



Nitrate of soda, Azotin, 



Muriate of potash, Ammonite, 



Sulphate of potash, Castor pomace, 



Dried blood. Bone and tankage, 



Dried ground meat, Plain superphosphates. 



A large percentage of commercial materials consists of 

 refuse matter from various industries. The composition of 

 these substances depends upon the mode of manufacture 

 carried on. The rapid progress in our manufacturing 

 industries is liable to affect, at any time, more or less seri- 

 ously, the composition of the refuse. To assist the farm- 

 ing community in a clear and ititelligent appreciation of 

 the various substances sold for manurial purposes, a h^e- 

 quent examination into the temporary characters of agri- 

 cultural chemicals and refuse materials offered in our 

 markets for manurial purposes is constantly carried on at 

 the laboratory of the station. 



Consumers of commercial manurial substances do well 

 to buy, whenever practicable, on guarantee of composi- 

 tion with reference to their essential constituents ; and to 

 see to it that the bill of sale recognizes that point of the 

 bargain. A mistake or misimderstanding may be readily 

 adjusted, in that case, between the contending parties. 

 The responsibility of the dealer ends with furnishing an 

 article corresponding, in its composition, with the lowest 

 stated quantity of each specified essential constituent. Our 

 present laws for the regulation of the trade in commercial 

 fertilizers include not only the various brands of compound 

 fertilizers, but also all materials, single or compound, with- 

 out reference to source, used for manurial purposes, when 

 offered for sale on our market at ten dollars or more per 

 ton. 



Copies of our present laws for the regulation of the trade 

 in commercial fertilizers may be had by all interested, on 

 application at the Massachusetts State Agricultiu"al Experi- 

 ment Station, Amherst, Mass. 



