RERAMIC STUDIO 
295 
The moulds being finished, the engraver closes them, 
covering the ends with the shapes and the caps fur 
the goblet, and with the counterpart for the tray. He 
ties them solidly and they are taken to the worker in pew- 
ter, to whose studio we shall follow them. 
CASTING IN PEWTER 
PREPARATIONS NECESSARY TO FINISH AN ARTISTIC PIECE OF 
PEWTER 
On entering the workshop of the founder, we observe 
first of all a stationary, isolated furnace (Fig. 22). It sup- 
ports a strong iron pot in which the metal is melted (Fig- 
(V* 
Fig. 22 — A, iron pot; B, circular table, flat rim; CCC, iron 
22, A). The edge of this kind of crucible is level with the 
flat top of the furnace, which serves as a circular table (Fig. 
22, BB). 
The furnace is heated with charcoal, wood, or petro- 
leum; the combustible itself being unimportant, provided 
that the resulting heat be strong enough to produce fusion, 
easy to control and of sufficiently long duration. 
On the furnace there are ladles of various sizes, having 
small spouts or beaks at the sides (Fig. 22, C). Near the 
furnace and in the heat lie several lingots of pewter, all of 
the same alloy which the founder has chosen to adopt; these 
lingots being provided in order to maintain without inter- 
ruption the same quantity of molten metal, and in case of 
too great heat, to lower its temperature. 
These variations are recognizable by the founder; the 
metal when too hot, changes color. It becomes yellow and 
blue, it wrinkles and develops at the surface a more abun- 
dant froth, which is removed and set aside. Formerly 
metal in fusion was covered with pieces of charcoal, which 
were put on and taken off, according as it was desired to 
hasten, or to retard liquefaction. 
Near the furnace stands a gas, or a charcoal stove, used 
to heat the separated parts of the mould. When these sec- 
tions reach the required temperature, they are glazed, and 
securely put together, so that the pewter may be poured 
into the thus completed mould. 
Subjoined are the principal alloys for pewter, with a 
statement of their qualities : 
I. White, pliant, vibrating, sonorous: 
Pure tin (Banca, Malacca, Detroit, 
etc 90 parts 
Regulus of antimony 9 parts 
Red copper 2 parts 
II. Having nearly the same properties as the first: 
Pure tin 88 parts 
Regulus 9 parts 
Red copper 3 parts 
It is possible to vary these alloys, but the formulae 
just quoted give good results in artistic pewter work. 
Other names could easily be given, but I do not think it 
possible to vary greatly from these quantities, if the metal 
used be genuine tin. 
Subjoined is the formula used by the pewterer Salmon 
in 1780; the metal, in this case, was desired to be pliant and 
malleable : 
Pure tin, 100 pounds 50 kilos 
Reddish copper, 1 pound 500 grammes 
Bismuth, \ pound 250 grammes 
Not far from the furnace stands a solid table with 
strong legs, upon which to take apart and put together the 
moulds. A basin holds the glaze which is applied with a 
soft brush to the inside walls of the mould, so as to prevent 
the pewter from adhering to the copper. 
This liquid glaze is composed of red, or yellow ochre, 
or of light clay, etc., finely pulverized, and capable of re- 
maining insoluble in a large quantity of water. 
We also need clamps, and spring-pincers which seize 
the extremities of the mould and tighten them; for it is 
important that the cores do not separate and loosen the 
shapes, which must be strongly held. 
l^^TThe instruments which serve to hold the moulds in all 
their parts, vary according to the forms of the latter. It is, 
above all, necessary that they be easily applied and re- 
moved, because the process of casting is rapid. 
Several mallets of soft wood to aid in removing the 
piece from the mould, must be within reach of the hand; as 
also a pointed knife with dull blade, together with pieces of 
felt cloth for holding the heated object. 
All these accessories are useful, for they aid in remov- 
ing the parts, which after the casting, would press too 
tightly on the shapes, or at the neck. 
Fig. 23— Pincers for moulds, 
