2 BULLETIN 158^ U. S. DEPARTMENT OF AGRICULTURE. 
enous fertilizers, such as cottonseed meal, dried blood, fish scrap, 
etc., are being used more and more for feed purposes, and the time 
can not be far distant when then' use as fertihzers will cease to be 
economic; thus a necessity for other and cheaper fertilizers of this 
type arises. Coupled with this is the desire of the chemist and the 
manufacturer to utihze in one way or another all waste products, 
whatsoever their nature, so that the number and kinds of nitrogenous 
materials which are used in the manufacture of fertihzers is on the 
increase. Described in the patent hterature and found on the 
market are a large number of fertihzers which may be characterized 
as ''processed," that is, the crude materials, not in themselves per- 
missible as fertihzers, are made to undergo some decided chemical 
change to render them suitable as plant nutrients. It has been 
found that the ' ' availabihty " of the crude substances is nearly al- 
ways greatly increased by such processing and that a much larger 
percentage of the nitrogen in the finished product is soluble in water, 
although the actual chemical changes produced seem to have re- 
ceived Httle attention. The chemical compounds in processed fer- 
tilizers which are here shown to have direct fertilizer significance 
have not been determined, other than to show that ammonia is 
formed during processing and that anmaonia is more readily pro- 
duced from the processed goods. 
Since the wastes from which this type of fertilizer is made contain 
more or less protein, or proteinlike substances, it seemed quite 
obvious that the finished fertihzers must contain more or less of the 
chemical compounds which would arise by such treatment from pure 
proteins in the laboratory. Since the action on plants of many of 
this class of compounds has been determined it is evident that the 
finding of such compounds in the fertilizers would throw much light 
on the question of the '^ availability" of the nitrogen in the fer- 
tilizer itself. 
BASE GOODS A TYPE OF PROCESSED FERTILIZER. 
For a chemical study of processed fertihzers a sample of '^ wet- 
mixed" or ''base goods" fertilizer was chosen as a representative of 
this type of fertilizer material. The base goods was obtained directly 
from the factory for use in this investigation. This fertilizer is made 
by the treatment of various trade wastes and refuse, such as hair, gar- 
bage tankage, leather scraps, etc., with rock phosphate and the 
requisite amount of sulphuric acid. These materials are mixed to- 
gether in a " den" and the resulting mass is allowed to stand for sev- 
eral days, until it is cool enough to be conveniently handled. In the 
course of the reaction the mass reaches a temperature approximating 
100° C, and the identity of the original substances is almost or en- 
tirely lost. Under these conditions it is certain that more or less 
