FOUNDERY. 
p'ortionate to the quantity of metal intend- 
ed to be cast. 
Some of these small- work founder’s fur- 
naces are like a smith’s forge, others stand 
a fewfeet under giound, for the more easily 
and safely taking out a weighty pot of 
metal; which is done by means of a circu- 
lar tongs that grasps round the top of the 
crucible. When the metal is melted the 
workman pours it through the chief canal of 
each mould, which conveys it to every dis- 
tinct pattern. 
When the moulds are cool the frames are 
unscrewed, or unwedged, and the cast- 
work taken out of the sand, which sand is 
worked over again for other castings. 
Foundery of statues. The casting of 
statues depends on the due preparation of 
the pit, the core, the wax, the outer mould, . 
the inferior furnace to melt off the wax, 
and the upper to fuse the metal. -The pit 
is a hole dug in a dry place something 
deeper than the intended figure, and made 
according to the prominence of certain 
parts thereof. The inside of the pit is com- 
monly lined with stone, or brick ; or, when 
the figure is very large, they sometimes 
work on the ground, and raise a proper 
fence to resist the impulsion of the melted 
metal. 
The inner mould, or core, is a rude mass, 
to which is given the intended attitude 
and contours. It is raised on an iron-grate, 
strong enough to sustain it, and is strengthen- 
ed within by several bars of iron. It is 
generally made either of potter’s clay, mix- 
ed with hair and horse-dung, or of plaster 
of Paris mixed with brick-dust. The use 
of the core is to support the wax, the shell, 
and lessen the weight of the metal. The 
iron bars and the core are taken out of the 
brass figure through an aperture left in it 
for that purpose, which is soldered up after- 
wards. It is necessary to leave some of the 
iron bars of the core that contribute to the 
steadiness of the projecting part within the 
brass figure. 
The wax is a representation of the in- 
tended statue. If it be a piece of sculpture; 
the wax should be all of the sculptor’s own 
band, who usually forms it on the core'; 
though it may be wrought separately, in 
cavities, moulded on a model, and after- 
wards arranged on the ribs of iron over the 
grate; filling the vacant space in the mid- 
dle with liquid plaster and brick-dust, 
whereby the inner core is proportioned as 
the sculptor carries on the wax. 
When the wax, which is the intended 
VOL. III. 
thickness of the metal, is finished, they fill 
small waxen tubes perpendicular to it from 
top to bottom, to serve both as canals for 
the conveyance of the metal to all parts of 
the work, and as vent-holes to give passage 
to the air, which would otherwise occasion 
great disorder when the hot metal came to 
encompass it. 
The work being brought thus far must 
be covered with its shell, which is a kind of 
crust laid over the wax, and which being of 
a soft matter easily receives the impression 
of every part, which is afterwards commu- 
nicated to the metal upon its taking the 
place of the wax, between the shell and the 
mould. The matter of this outer mould is 
varied according as different layers are 
applied. The first is generally a composi- 
tion of clay and old white crucibles well 
ground and sifted, and mixed up with 
water to the consistence of a colour fit for 
painting: accordingly they apply it with a 
pencil, laying it seven or eight times over, 
and letting it dry between whiles. For the 
second impression they add liorse-dung and 
natural earth to the former composition. 
The third impression is only horse-dung and 
earth. Lastly, the shell is finished by laying 
on several more impressions of this last mat- 
ter, made very thick with the hand. 
The shell thus finished is secured by seve- 
ral iron girts bound round it, at about half a 
foot distance from each other, and fasten- 
ed at the bottom to the grate under the 
statue, and at top to a circle of iron where 
they all terminate. 
If the statue be so big that it would not 
be easy to move the moulds with safety, 
they must be wrought on the spot where it 
is to be cast. This is performed two ways : 
in the first a square hole is dug under 
ground, much bigger than the mould to be 
made therein, and its inside lined with walls 
of free stone or brick. At the bottom is 
made a hole of the same materials with a 
kind of furnace, having its aperture out- 
wards : in this is a fire made to dry the 
mould, and afterwards melt the wax. Over 
this furnace is placed the grate, and upon 
this the mould, &c. formed as above. 
Lastly, at one of the edges of the square 
pit is made another large furnace to melt 
the metal. In the other way it is sufficient 
to work the mould above ground, but with 
the like precaution of a furnace and grate 
underneath. When finished, four wails are 
to be run around it, and by the side there- 
of a massive made for a melting-furnace. 
For the rest, the method is the same in 
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