than that of silver cleaning.

Sec. 135. Preparing Surfaces for Gilding.

Ordinary brass work--rough or smooth--may for purposes of
preservation be dipped, scratch-brushed, and gilt at once. Seven
years ago the writer gilt the inside of the head of a copper water
still, and simply scratch-brushed it; it is to-day in as good order as
when it was first done. If it is intended to gild work from the
first, with the view of making an exceptionally fine job of it,
"gilding metal," i.e. brass containing one to one and a quarter
ounces of zinc to the pound of copper may be specified. From its
costliness, however, this is only desirable for small work.

Iron and steel are generally given a preliminary coating of copper,
but this may be dispensed with though with no advantage--by using a
particular process of gilding.

Base metals, zinc, pewter, lead, etc, are first coppered in a cyanide
of copper solution, as will be described under the head of
Copper-plating. If it is intended to gild soldered articles,
the preliminary coating of copper is essential.

The most convenient vessel for holding a gilding solution is
undoubtedly one formed of enamelled iron. Particularly useful are the
buckets and "billies" (i.e. cylindrical cans) made of this material.
These vessels may be heated without any fear of a smash, and do not
appear to be appreciably affected by gilding solutions--at all events
during several days or weeks. The avoidance of all risk of breakage
when twenty or thirty pounds' worth of solution is in question is a
matter of importance.

Under no circumstances is it desirable to use anything but the purest
gold and best fused cyanide (called "gold" cyanide) in the preparation
of the solutions. The appearance of a pure gold deposit is far richer
than of one containing silver, and its resistance to the atmosphere is
perfect; moreover, in chemico-physical processes one has the
satisfaction of knowing what one is dealing with.

Sec. 136. Gilding Solutions.

The strength of solution necessary for gilding brass, copper, and
silver is not very material. About one to two pounds of "gold"
potassium cyanide (? 96 per cent KCN) per gallon does very well. The
gold is best introduced by electrolysing from a large to a small gold
electrode. One purchases a plate of pure gold either from the mint or
from reliable metallurgists (say Messrs. Johnson and Matthey of
London), and from this electrodes are cut.

The rel