BULLETIN OF THE 
UOTiMNTOFAfflOlM 
No. 97 
Contribution from the Bureau of Soils, Milton Whitney, Chief. 
June 12, 1914. 
(PROFESSIONAL PAPER.) 
IDENTIFICATION 
OF COMMERCIAL 
MATERIALS. 
FERTILIZER 
By William H. Fry, Scientist in Soil Laboratory Investigations. 
INTRODUCTION. 
In working with commercial fertilizers it is often desirable to know 
not only the percentages of the various ingredients as given by chemi- 
cal analysis but also the compounds in which these occur in the fer- 
tilizer, i. e. ; the carriers of these ingredients. The calculation of the 
rational composition from the ultimate analysis in the case of salts 
gives results which are open to doubt and requires a much more com- 
plete analysis than is usually made. In the case of organic materials 
such a calculation is practically impossible. It, therefore, becomes 
necessary to identify a great number of the substances occurring in 
commercial fertilizers by means which give the compounds as dis- 
tinguished from the chemical ingredients of these compounds. 
The following substances were chosen for examination: 
Potassium chloride. 
Potassium sulphate. 
Ammonium sulphate. 
Kainite. 
Sodium nitrate. 
Superphosphate. 
Calcium nitrate. 
Lime. 
Apatite. 
Phosphate rock. 
Gypsum. 
Limestone. 
Calcium cyanamid. 
Basic slag. 
Ground rocks and minerals. 
Cottonseed meal. 
Raw bone meal. 
Steamed bone meal. 
Peat, humus, muck, etc. 
Dried blood. 
Slaughterhouse tankage. 
Garbage tankage. 
Fish scrap. 
Dissolved bone black. 
Shells. 
Note.— This 
and is intended 
3&791°- 
)r identifying the carriers of the various fertilizing ingredients, 
guide to those studying this phase of the fertilizer question. 
