GIL 
may be made to cover a larger surface than 
in any other way of gilding on metals ; five 
grains of gold will completely gild both the 
upper and under surfaces of one-hundred 
and forty-four copper buttons each of them 
an inch in diameter. 
There is no metal, the gilding of which 
presents so many diflicnlties as iron, or ra- 
ther steel. If the method of simple bur- 
nishing down is had recourse to, the heat re- 
quisite for this purpose will, in many cases, 
bring the temper of the steel too low: 
on such occasions, the way already de- 
scribed for gilding on copper, is sometimes 
practised ; that is, the parts of the steel to 
be gilded, are pencilled over with nitrate 
of mercury, by which they are covered with 
a slightly-adhering coat of mercury; then 
the amalgam is applied, and the gilding 
finished in the usual way. The objections 
to this mode of proceeding are, first, that a 
considerable heat is required, though infe- 
rior to that requisite for burnishing down ; 
and secondly, that even with all possible 
care the gilding is apt to be rough and scale 
off. A very considerable improvement in 
this way of gilding is to trace the figure of 
the gilding on the steel first of all, with a 
brush charged with a strong solution of sul- 
phated copper, in consequence of which a 
pretty thick plate of this metal is deposited 
on the steel, to which it may be made to 
adhere, with considerable firmness, by 
means of the burnisher ; thus the giiding is, 
in fact, performed upon the copper. 
A new method of gold-gilding upon steel 
has lately been published, possessed of 
many advantages over the others, and pro- 
bably in time may attain to a very high de- 
gree of perfection. It depends upon the 
well-known fact, that if sulphuric ether and 
nitro-muriate of gold are mixed together, 
the ether will, by degrees, separate from 
the acid nearly the whole of the gold, and 
retain it for some time in solution, in nearly 
a metallic state. If ether, thus charged 
with gold, is spread, by means of a pen or 
fine brush, on the surface of highly-polished 
steel, the ether presently evaporates, leav- 
ing the gold behind in close contact with 
the steel, and the adhesion is considerably 
improved by the subsequent application of 
the burnisher. The dearness, and espe- 
cially the rapid volatility of ether, are, at 
first, objections of some moment, but may 
be got over by using the best oil of turpen- 
tine instead of ether, which has nearly the 
same efficacy in decomposing the nitro-mu- 
GIN 
riate of gold, and is both cheaper, and not 
so very quickly evaporable. 
Gold-gilding upon silver is, we believe, at 
present entirely disused. It was perform- 
ed in the following manner : a saturated so- 
lution of gold, in nitro-muriatic acid, was 
poured upon some linen rags, and when 
they were become dry, they were heaped 
in a plate, and touched with a hot coal. 
The fire gradually spread through the mass, 
and reduced it to a heavy black ash. A 
soft cork, being moistened in water, was 
dipped in this ash, to which a part of it ad- 
hered, and was then rubbed on the surface 
of polished silver, upon which the minute 
particles of gold became fixed, and covered 
it with an extremely thin coating, which, 
when burnished, exhibited the genuine co- 
lour and lustre of the precious metal. Al- 
lan's Did. 
GILL, a measure of capacity, contain- 
ing a quarter of a pint. 
GILT varnish. See Varnish. 
GIMBALS, in sea affairs, the brass rings 
by which a sea compass is suspended in its 
box, so as to counteract the effect of the 
ship’s motion, and keep the card horizontal. 
GIMBLETING, a term applied to the 
anchor to denote the action of turning it 
round by the stock, so that the motion of 
the stock appears similar to that of the 
handle of a gimblet when it is employed. 
GIN. See Geneva. 
Gin, in mechanics, a machine for driving 
piles, fitted with a windlass and winches at 
each end, where eight or nine men heave, 
and round which a rope is reeved, that goes 
over the wheel at the top. 
GINANNIA, in botany, a genus of the 
Enneandria Monogynia class and order. 
Natural order of Lomentaceae. Legumi- 
nosae, Jussieu. Essential character : calyx 
double, both one-leafed ; petals three, 
fringed, spreading ; germ pedicelled, with a 
membranaceous wing at top ; legume. 
There is but one species, t>iz. G. guianensis, 
a shrub about fifteen feet high ; a native of 
the forests of Guiana. 
GINGER, in botany. See Zinzi,ber. 
GINORA, in botany, so called in honour 
of the Marquis Carlo Ginori, a genus of the 
Dodecandria Monogynia class and order. 
Natural order of Salicariae, Jussieu. Es- 
sential character: calyx six-cleft; petals 
six ; capsule one-celled, four-valved, co- 
loured, containing many seeds. There is 
but one species, viz. G. Americana, an ele- 
gant little shrub about four feet high ; it is 
