st part, again
separated on cooling, particularly those rich in stearine. All fats are
taken up by ether but those containing stearine in the smallest
quantity.

Their specific gravities fluctuate between .91 and .93. When heated,
fats assume a dark color, and boil between 482 deg. and 572 deg. Fahr., but the
boiling-point continuously rises, while an uninterrupted decomposition
proceeds. From oxide of glycyl ensues acroline; oleic acid affords a
fatty acid, and among the decomposition products of fats containing
stearine and margarine are found pure margaric acid, and, at the same
time, some hydro-carbons are formed. When exposed quickly to a high
temperature, fats are completely decomposed. (Oil gas.) In closed
vessels the pure fats undergo no change, but, placed in thin layers in
the air, the fats containing oleine and oline rapidly absorb oxygen
under the strong evolution of heat, which will inflame porous bodies, as
cotton wool. The purer the fats are the more quickly their oxidation
results. When the fats contain slimy materials, these latter can be
destroyed with a little oxide of lead and water. (Preparation for the
application of varnishes.) The action of nitric acid, nitrous acid,
chlorine, sulphuric acid, &c., on fats is the same as that of these
bodies on the fatty acids. The fatty oils dissolve sulphur in the heat
which is again partly precipitated on cooling. When sulphur is heated
with fatty oils, namely, with linseed oil, it dissolves by degrees, and
a thick dark mass is formed, the so-called balsam of sulphur. By raising
the heat, a violent reaction ensues under the evolution of sulphuretted
hydrogen, and, at the same time, an oil resembling oil of garlic
volatilizes. This oil begins to boil at 160 deg. Fahr., but its
boiling-point rises continually.

* * * * *

PERFUMES AS PREVENTIVES OF MOULDINESS.

An interesting paper on this subject has been published by Dr.
Macculloch. We presume our readers are aware that mouldiness is
occasioned by the growth of minute vegetables. Ink, paste, leather, and
seeds, are the substances that most frequently suffer from it. The
effect of cloves in preserving ink is well known; any of the essential
oils answer equally well. Leather may be kept free from mould by the
same substances. Thus Russian leather, which is perfumed with the tar of
birch, never becomes mouldy; indeed it prevents it from occurring in
other bodies. A few drops o