222 BOARD OF AGRICULTURE. [Pub. Doc. 



of the experiment stations of the eastern States, and is re- 

 produced here in abbreviated form : — 



Cents 

 per Pound. 



Nitrogen in nitrates 16.5 



Nitrogen in ammonia salts, ....... 16.5 



Organic nitrogen, 22.5 



Phosphoric acid, soluble in water, 4.5 



Phosphoric acid, insoluble, 2.0 



Potash in sulphate of potash, 5.0 



Potash in muriate of potash, 4.0 



With these two sets of figures of the analysis and trade 

 values at hand it will be simple to compute the trade value 

 of any fertilizer. An example will make this clear. Take 

 the mixed fertilizer mentioned previously in this article, a 

 2-5-6 brand, and let it be assumed that four-fifths of the 

 phosphoric acid is soluble in water, and one-fifth insoluble, 

 and that all the potash is in the form of muriate of potash. 

 It must be recognized that two fertilizers having the same 

 trade value may still vary in their crop-producing power, 

 dependent upon the materials used in compounding them. 

 The value of this brand would be computed as follows : — 



1 per cent nitrogen (org-anic) equals 20 jjounds per ton, 



at 22.5 cents equals $4.50 



1 per cent nitrogen (nitrate) equals 20 pounds per ton, 



at 16.5 cents equals 3.30 



4 per cent phosphoric acid equals 80 jiounds per ton, at 



4.5 cents equals 3.60 



1 per cent phosphoric acid equals 20 pounds per ton, at 



2 cents equals .40 



6 i^er cent potash equals 120 pounds per ton, at 4 cents 



equals 4.80 



$16.60 



This particular material should cost $10.60 per ton at 

 retail in the large market centers, such as New Yoi'k or 

 Boston; and to this, of course, must be added the cost of 

 new bags and freight to the buyer's station. 



^N^itrate of soda analyzing 15.65 per cent nitrogen would 



