100 AGRICULTURAL EXPERIMENT STATION. [Jan. 



sidered of douljtful merit. The use of the highest trade values 

 is but justice to these articles in which the costliest materials 

 are expected to be used. 



In most cases the valuation of the ingredients in superphos- 

 phates and specials falls below the retail price of the goods. 

 The difference between the two figures represents the manufac- 

 turer's charges for converting raw materials into manufactured 

 articles. These charges are for grinding and mixing, bagging 

 or barrelling, storage and transportation, commission to agents 

 and dealers, long credits, interest on investment, bad debts, 

 and finally profits. 



The prices stated in this report in connection with analyses 

 of commercial fertilizers refer to their cost per ton of 2,000 lbs., 

 on board of car or boat near the factory or place of general dis- 

 tribution. To obtain the valuation of a fertilizer (i. e., the 

 money-worth of its fertilizing ingredients), we multiply the 

 pounds per ton of nitrogen, etc., by the trade value per pound. 

 We thus get the values per ton of the several ingredients, 

 and, adding them together, we obtain the total valuation per 

 ton. 



The mechanical condition of any fertilizing material, simple 

 or compound, deserves the most serious consideration of farm- 

 ers, when articles of a similar chemical character are ofiered 

 for their choice. The degree of pulverization controls, almost 

 without exception, under similar conditions, the rate of solu- 

 bility, and the more or less rapid diffusion of the difierent 

 articles of plant food throughout the soil. 



The state of moisture exerts a no less important influence on 

 the pecuniary value, in case of one and the same kind of sub- 

 stance. Two samples of fish fertilizer, although equally pure, 

 may diflfer from 50 to 100 per cent, in commercial value, on 

 account of mere diflerences in moisture. 



Crude stock for the manufacture of fertilizers and refuse ma- 

 terial of various descriptions sent to the Station for examination 

 are valued with reference to the market prices of their principal 

 constituents, taking into consideration at the same time their 

 general fitness for speedy action. 



A large percentage of commercial fertilizing material consists 

 of refuse matter from various industries. The composition of 

 these substances depends on the mode of manufacture carried 



