44 BULLETIN 769, U. S. DEPARTMENT OF AGRICULTURE. 
country come from cottonseed oil. Appreciable quantities of foots 
are derived also from the refining of peanut, coconut, soy bean, and 
other vegetable oils which are treated with caustic soda to make 
them suitable for food purposes. A detailed description of the 
methods by which these various products are obtained would involve 
more technical detail than properly belongs to a treatise of this kind. 
Suffice it to say that acidulated soap stock, or black grease, as it is 
often called, is made by neutralizing with sulphuric acid the caustic 
soda present in raw foots. If, after neutralizing with acid and 
separating the small amount of glycerin from the large quantity of 
sodium sulphate liquor formed during this process, the fatty acids are 
distilled, the resulting product is known as distilled fatty acids, or, 
sometimes, distilled cottonseed foots. These fatty acids may also be 
further treated by pressing them according to a method similar to 
that employed in obtaining oleostearin and the oil from oleo stock 
(page 35). The liquid acids manufactured in this way are known 
in the trade as red oil, and the solid acids usually as stearic acid. 
Properly speaking, these solid acids are by no means pure stearic acid, 
but a mixture of stearic, palmitic, and other saturated fatty acids. 
The red oil is very largely crude oleic acid, although it too may contain 
a certain amount of other unsaturated fatty acids and a small quan- 
tity of palmitic and stearic acids. To the second group of deriva- 
tives belong the stearins and oleo oils. The method of separating 
the higher from the lower melting portions of tallow, and the chilling 
out by the wintering process of the cottonseed stearin from cotton- 
seed oil have already been described (page 8). 
In figuring our production of fats and oils it is obviously incorrect 
to include these derivative products, which have already been reported 
in the production of the crude oils, tallows, greases, etc.. from which 
they are obtained. 
Vegetable stearin, a term properly applied only to the higher melt- 
ing portion of vegetable oils separated by some chilling process, has 
recently been used as a synonym for hydrogenated oil. These hard- 
ened fats made by the hydrogenation process, however, should not 
be confused in this way with the natural vegetable stearins. The 
figures given in Table 11 for the production of vegetable stearins 
probably refer, to some extent at least, to hydrogenated oils, due to 
this unfortunate confusion of terms in modern trade practice. 
SUMMARY. 
During the recent Great War, the matter of maintaining an adequate 
supply of fats and oils became a very important factor. Although 
the allied nations were able to secure enough to meet their military 
and civil needs, Germany soon found herself seriously embarrassed 
bv a lack of all fats. Had her Government heeded the advice of those 
