890 ANNUAL REPORT OF THE Off. Doc. 



present in green sand uiarl 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 quanti- 

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

 ganic .matter. (5) Chloriu; this determination is made to afford a 

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

 chlorid or muriate, the cheaper source. The computation is made 

 on the assumption that the chlorin present, unless in excess, has 

 been introduced in the foim of muriate of potash; but doubtless 

 there are occasional exceptions to this rule. One part of chlorin 

 combines with 1.326 parts of potash to form the pure muriate; know- 

 ing the chlorin, it is, therefore, easy to compute the poiash equiva- 

 len thereto. (7) In the case of ground bone, the state of sub-divi- 

 sion is determined by sifting through accurately made sieves: the 

 cost of preparation and especially the promptness of action of bone 

 in the soil depends very largely on the fineness 'of its particles, the 

 finer being much more quickly useful to the i)lant. 



The law having required the manufacturer to guarantee the 

 amount of certain valuable ingredients present in any brand he may 

 put upon the market, chemical analysis is employed to verify the 

 guaranties stamped upon the fertilizer sacks. It has, therefore, 

 been deemed desirable in this report to enter the guaranty filed by 

 the manufacturer in the office of the Secretary of Agriculture, in 

 such connection with the analvtical results that the two mav be 

 compared. An unfortunate practice has grov»^n up among manu- 

 facturers of so wording the guaranty that it seems to declare the 

 presence in the goods of an amount of a valuable constituent rang- 

 ing from a certain minimum to a much higher maximum; thus, "Pot- 

 ash, 2 to 4 per cent." is a guaranty not infrequently given. In 

 reality, the sole guaranty is for 2 per cent. The guaranteed amounts 

 given for each brand in the following tables, are copied from the 

 guaranties filed by the maker of the goods with the Secretary of 

 Agriculture, the lowest figure given for any constituent being con- 

 sidered to be the amount guaranteed. For compactness and because 

 no essentially important fact is suppressed thereby, the guaranties 

 for soluble and reverted phosphoric acid have not been given sepa- 

 rately, but are combined into a single guaranty for available phos- 

 phoric acid; in cases where the maker's guaranty does not specific- 

 ally mention available phosphoric acid, the sum of the lowest figures 

 given by him for soluble and reverted phosphoric acid is used. 

 The law of 1879 allowed the maker to express his guaranty for 

 nitrogen either in terms of that element or in terms of the am 

 monia equivalent thereto; since ammonia is composed of three 



