ould, however, a doubt exist, add
to the distillate a little acetate of potash and strong sulphuric acid,
and heat the mixture in a test-tube to the boiling-point, when the
characteristic odor of acetic ether will be manifest, if any alcohol be
present.

* * * * *

DETECTION OF POPPY AND OTHER DRYING OILS IN ALMOND AND OLIVE OILS.

It is known that the olein of the drying oils may be distinguished from
the olein of those oils which remain greasy in the air by the first not
being convertible into elaidic acid, consequently it does not become
solid. Professor Wimmer has recently proposed a convenient method for
the formation of elaidin, which is applicable for the purpose of
detecting the adulteration of almond and olive oils with drying oils. He
produces nitrous acid by treating iron filings in a glass bottle with
nitric acid. The vapor of nitrous acid is conducted through a glass tube
into water, upon which the oil to be tested is placed. If the oil of
almonds or olives contains only a small quantity of poppy oil when thus
treated, it is entirely converted into crystallized elaidin, whilst the
poppy oil swims on the top in drops.

* * * * *

COLORING MATTER OF VOLATILE OILS.

BY G.E. SACHSSE.

It is well known that most ethereal oils are colorless; however, there
are a great number colored, some of which are blue, some green, and some
yellow. Up to the present time the question has not been decided,
whether it is the necessary property of ethereal oils to have a color,
or whether their color is not due to the presence of some coloring
matter which can be removed. It is most probable that their color arises
from the presence of a foreign substance, as the colored ethereal oils
can at first, by careful distillation, be obtained colorless, whilst
later the colored portion passes over. Subsequent appearances lead to
the solution of the question, and are certain evidence that ethereal
oils, when they are colored, owe their color to peculiar substances
which, by certain conditions, may be communicated from one oil to
another. When a mixture of oils of wormwood, lemons, and cloves is
subjected to distillation, the previously green-colored oil of wormwood
passes over, at the commencement, colorless, while, towards the end of
the distillation, after the receiver has been frequently charged, the
oil of cloves distils over in very dense drops of a dark green