848 



ANNUAL REPORT OF THE 



Off. Doc. 



used, or, in other words, upon the ever-ruling elements in the 

 commercial world of "JSupplj and Demand." 



The agricultural value depends upon the ability of the particular 

 fertilizer or phosphate in question to improve the fertility or pro- 

 ductive capacity of a particular soil. Hence, it will be seen that the 

 agricultural value, within certain limits, is not directly dependent 

 upon the commercial value (and vice versa), and is a value that 

 changes with dilierent soils. 



To illustrate; suppose a particular class of soils contain all the 

 phosphates necessary for crops and that the application of any 

 more phosphates give no returns whatever in increasing yields. This 

 w.»uld mean that for that particular piece of land phosphates had 

 no value agriculturally; jet that would not affect the market or 

 commercial value of the phosphate. To illustrate further; sugar 

 lif!s a commercial value of |i00.00 per ton, while Dissolved SoutU 

 Carolina rock can be purchased for one-tenth that sum. From a 

 fertilizing standpoint, it is doubtful if an application of sugar would 

 have any effect on the yield of crops, while the phosphate might 

 double them, and thus have double the agricultural value of the 

 sugar. Again, clover hay, for instance, has double the fertilizing 

 and feeding value of timothy hay, yet the commercial or market 

 value of timothy hay is always the more. 



The following is the commercial value of phosphoric acid in differ- 

 ent phosphatic materials according to the trade valuations in Penn- 

 sylvania in 1901: 



a 



3 

 o 



5 



Soluble phosphoric acid in bone fertilizers, 



Soluble phosphoric acid in rock fertilizers 



Reverted phosphoric acid in bone fertilizers 



Reverted phosphoric acid in rock fertilizers 



Insoluble phosphoric acid in bone fertilizers, 



Insoluble phosphoric acid in rock fertilizers 



Total phosphoric acid in fine raw bone, tankage and fish fertilizer 



Total phosphoric acid Iq medium bone and tankage, 



Total phosphoric acid in coarse bone and tankage, 



Total phosphoric acid in cotton-seed meal 



Castor pomace and wood ashes, 



6 



3 



4Vi 



2^ 



2 



1% 



8% 



3 



2% 



4 



4 



