with several organic substances, imparting to them peculiar colors.
It colors the skin brown, but the stain soon disappears.

Chloride of Iodine--Is formed by passing chlorine into
a bottle containing some iodine. This can be readily done
by pouring one ounce and a half of muriatic acid upon a quarter
of an ounce of powdered black oxide of manganese, and heat it
gradually in a flask, to which is adapted a bent glass tube.
This tube must connect with the bottle containing the iodine,
and the yellowish-green gas disengaged will readily combine with
the iodine, forming a deep red liquid, and the operation is complete.
The use of chloride of iodine will be referred to in connection
with the Accelerators.

[page 86]

Iodides.--The iodide treated with the oil of vitriol,
instantly produces a considerable deposit of iodine; and if
the mixture be heated, intense violent vapors are disengaged.
The reaction is due to the decomposition of oil of vitriol
by iodohydric acid, water and sulphurous acid being formed,
and iodine set free. The iodides in solution are decomposed
by chlorine, iodine being precipitated, the smallest quantity
of which in solution is instantly detected by its imparting
to starch an intensely blue color.

Iodide of Potassium.*--This compound is easily made in the following manner:
Subject to a moderate heat a mixture of 100 parts of iodine,
75 of carbonate of potash, 30 of iron filings, and 120 parts of water.
This mass must be thoroughly dried and then heated to redness;