390 Report of the Inspection Work of the 



goods, the selling price should not exceed the commercial valuation 

 by more than $5. 



5. For greatest economy, farmers are advised to purchase unmixed 

 materials and do their own mixing ; or, in the case of club.^, several 

 farmers can purchase their unmixed materials and hire a fertilizer 

 manufacturer to do the mixing for them. 



6. Illustrations are given of three types of plant- food mixtures : 

 (a) A mixture with phosphoric acid high in amount in relation to 

 nitrogen and potash ; (b) a mixture of high-grade, in which the 

 potash is high in amount in relation to nitrogen and phosphoric acid ; 

 (c) a mixture of high-grade, containing nitrogen, phosphoric acid 

 and potash in quantities more nearly equal than in the other mix- 

 tures. 



7. A general review is given covering the work of the Station in 

 collecting and analyzing fertilizers during the last five years. In 

 general, it is shown that the number of manufacturers of commercial 

 fertilizers and of brands of fertilizers has decreased since 1899, owing 

 to the requirement of a license fee of $20 for each brand offered for 

 sale. In respect to composition, the average variation from year to 

 year has been within narrow limits. The number of brands found 

 below guarantee has steadily decreased. The average selling price 

 per ton has also gradually decreased and also the difference between 

 the selling price and commercial valuation. 



