AGRICULTURAL EXPERIMENT STATION. 27 



FERTILIZERS. 



INSPECTION OF FERTILIZERS.* 



The inspection of the various brands of fertilizers sold in the 

 State has for its object (1) the comparison of the actual composi- 

 tion of these brands with the guaranteed composition, this being 

 required by law, and (2) the determination of their relative values. 

 In carrying out this inspection the fertilizers must be sampled in the 

 hands of dealei's or consumers, analj'zed, and their values then 

 calculated on the basis of ruling commercial prices. 



There are given below the history, analyses and valuations of 

 eighty-five samples, taken from thirty-eight brands, with such pre- 

 ceding explanations as are deemed necessary for a clear under- 

 standing of the main facts pertaining to the composition of com- 

 mercial fertilizers, and of the real significance that the analyses 

 and valuations have for the consumer. f 



Valuable Ingkkdients of Fertilizers. The ingredients of 

 commercial ferlilizers upon which both tbi-ir agricultural and 

 commercial values chiefly depend are nitrogen, phosphoric acid and 

 potash. Besides these more valuable ingredients, sulphuric acid 

 and lime are always present in superphosphates in considerable 

 quantities, being a necessary accompaniment of phosphoric acid as 

 it exists in nearly all manufactured fertilizers. Fertilizers also 

 contain soda, magnesia, iron, alumina, chlorine, silica and more or 

 less organic matter, the number and quanitit}^ of the ingredients 

 varying according to the raw materials used 



Nitrogen is the most cosily of the three important ingredients 

 mentioned, and adds largely to the commercial value of all the 

 fertilizers sold in Maine, with a few exceptions. It is found in the 

 markets in quite a variety of substances which are used by manu- 

 facturers to supply this ingredient to mixed fertilizers, but which 

 are available for fertilizing purposes when purchased unmixed with 

 anything else. 



*The explanations in regard to the composition and valuation of fertilizers which are made 

 under this head arc mainly reprinted from the previous reports of the Station, with such 

 changes as are necessaiy. The apology for quoting so largelj' Irom a previous report, is that 

 there are no new facts to be stated, and that to express the old facts in a new form would 

 probably not add anything in value or clearness to the explanations already made. These 

 explanations will not be repeated in further reports, so that those who receive this report will 

 do well to preserve it for future reference. 



tPreviously printed in bulletins 23 and 25. 



