No. 7. DEPARTMENT OE^ AGRICULTURE. 679 



The result obtained by use of this schedule does not cover the 

 items of mixing, bagging, freight and agents' commission. To cover 

 these, allowances are made as follows: 



For freight, an allowance of |2.00 per ton on all fertilizers. 



For bagging, an allowance of fl.OO per ton on all fertilizers, except 

 when sold in original packages. 



For mixing, an allowance of fl.OO per ton on complete fertilizers 

 aad rock-and-potash goods. 



For agents' commission, an allowance of 20 per cent, is added to 

 the cash value of the goods ready for shipment. 



FERTILIZER ANALYSES JANUARY 1, TO AUGUST 1, 1910 



Since January 1, 1910, there have been received from authorized 

 sampling agents eighteen hundred and nine fertilizer samples, of 

 which six hundred and sixty-nine were subjected to analysis. Prefer- 

 ence is given to those which have not been recently analyzed. In 

 cases where two or more samples representing the same brand were 

 received, equal portion from several samples were united, and the 

 composite sample was subjected to analysis. 



The samples analyzed group themselves as follows: 436 complete 

 fertilizers, furnishing phosphoric acid, potash and nitrogen; 8 dis- 

 solved bones, furnishing phosphoric acid and nitrogen ; 123 rock-and- 

 potash fertilizers, furnishing phosphoric acid and potash; 47 acidu- 

 lated rock phosphates, furnishing phosphoric acid only; 24 ground 

 bones, furnishing phosphoric acid and nitrogen, and 31 miscella- 

 neous samples, which group includes substances not properly classi- 

 fied under the foregoing heads. 



The determinations to which a complete fertilizer is subjected are 

 as follows: (1) Moisture, useful for the comparison of analyses, for 

 indication of dry condition and fitness for drilling, and also of the 

 conditions under which the fertilizer was kept in the warehouse. (2) 

 Phosphoric acid — total, that portion soluble in water, and of the 

 residue, that portion not soluble in warm ammonia citrate solution 

 (a solution supposed to represent the action of plant roots upon 

 the fertilizer), which is assumed to have little immediate food value. 

 By difference, it is easy to compute the so-called "reverted" acid, 

 which is the portion insoluble in water but soluble in the citrate. 

 The sum of the soluable and reverted is commonly called the "avail- 

 able" phosphoric acid. (3) Potash soluble in water — most of that 

 present in green sand marl and crushed minerals, and even some of 

 that present in vegetable materials such as cotton-seed meal, not 

 being included because insoluble in water even after long boiling. 

 (4) Nitrogen — This element is determined by a method which simply 

 accounts for all present, without distinguishing between the qunnli- 

 ties present in the several forms of ammonium salts, nitrates or or- 

 ganic matter. (5) Chlorin — this determination is made to afford a 

 basis for estimating the proportion of the potash that is present as 



