New York Agricultural Experiment Station. 127 



previously stated, the nitrogen in fertilizers is always combined with 

 other elements and may be present in one or more different forms ; 

 (1) in the form of nitrates, as nitrate of soda ; (2) in tlie form of 

 ammonia compounds, as sulphate of ammonia ; and (3) in the form 

 of organic matter, animal or vegetable, as dried blood, meat, tobacco 

 stems, etc. Chemical analysis according to official methods does not 

 attempt to ascertain and state in which form or forms the nitrogen is 

 present in a fertilizer. 



When, therefore, nitrogen is expressed in an analysis or guarantee 

 simply as "nitrogen," it refers to the entire amount of nitrogen 

 present without regard to the particular form or forms in which it 

 is present. 



(b) Ammonia consists of nitrogen comhined ivith hydrogen. A 

 pound of nitrogen will form more than a pound of ammonia, be- 

 cause the ammonia formed from a pound of nitrogen wnll contain 

 that pound of nitrogen plus the necessary amount of hydrogen added 

 to form ammonia. The chemical relations of nitrogen and ammonia 

 are such that 14 pounds of nitrogen, will unite with exactly 3 pounds 

 of hydrogen, and will, therefore, produce just 17 pounds of 

 ammonia; or 1 pound of nitrogen will make 1.214: pounds of 

 ammonia. 



Manufacturers very commonly express the amount of nitrogen in 

 the equivalent of ammonia, probably for the reason that, expressed 

 as ammonia, larger figures are obtained than would be, if expressed 

 as nitrogen ; and the fertilizers appear to farmers to contain more 

 nitrogen. This methocl is not in accordance with present legal 

 requirements, and farmers should Jcnow that ^^ nitrogen'''' and 

 " ammonia " are not the same thing^ since one pound of am^mo- 

 oiia contains only ahout eight-tenths of a pound of nitrogen. 



(c) Nitrogen equal {or equivalent) to Ammonia is a form of 

 expression which simply means that the nitrogen is stated not as 

 nitrogen but as ammonia. 



It would be better on every account if all guarantees stated simply 

 nitrogen and never mentioned ammonia at all. As a matter of fact, 

 compounds of ammonia are quite uncommon in commercial fer- 

 tilizers, because nitrogen in this form is the most expensive and 

 therefore least used. Strictly speaking, the term ammonia should 

 never be used except when sulphate of ammonia or some similar 

 •compound is present in the fertilizer. 



