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SELECTED ARTICLES. 
of caustic potassa, which saponifies the oil, but dissolves only 
a small quantity of the fatty substance; the yellow fatty acids 
are precipitated from the alkaline solution by the hydrochloric 
acid, and we may by dissolving them in the caustic solution, 
much diluted, (5 or 6 drops to the ounce of water,) and preci- 
pitating anew, obtain them free from color. To deprive it of the 
latter substance, or the solid fatty matter, we must treat it with 
cold alcohol, in which it is not soluble. I have never as yet 
been able to obtain it perfectly free from these two fatty bodies. 
Such as I have obtained it, it has the appearance of a yellow 
fat, easily fusible, becoming liquid even at 42°; when it be- 
comes solid, it is transparent and of a yellowish brown; it is 
volatile without decomposition, but gives on dry distillation 
a rather brownish fat, but little soluble in alcohol, and leaves 
a residue of carbon. It is insoluble in water, but if, when 
melted, we pour upon it some hot water, it becomes transpa- 
rent, swells up slightly, and becomes of a paler yellow, as if 
the water had combined with it chemically. When moist- 
ened with water, and exposed a longtime to the air and light, 
it bleaches completely, and is converted into a fatty matter 
soluble with difficulty in alcohol, and precipitates in light 
white flocculi from a boiling saturated solution in alcohol. 
The yellow fat is soluble in alcohol in very small quantity. 
In this solution it does not bleach sensibly in the same pe- 
riod of time in which it becomes white in water. The alco- 
holic solution is precipitated by water, and then assumes a 
pale yellow milky aspect, which it retains even after the evapo- 
ration of the alcohol. It is deposited from the alcoholic solution 
during its spontaneous evaporation in the form of crystalline 
granules. Ether dissolves it largely, and leaves it, after eva- 
poration, of a yellow color and transparent. In contact with 
concentrated sulphuric acid, it becomes brown, is dissolved spa- 
ringly, but with alteration, and gives a yellowish-brown liquid, 
which is precipitated by water, of a grayish-white color. It 
dissolves, but in very small quantity, in caustic potassa, and 
when thus dissolved, if it be exposed for some time to the 
influence of th,e air and light, it bleaches. It is precipitated 
