Medals
If it is desired to obtain a convex and a concave plaster-mould from a medal, press tin-foil close into every part of the surface and pour on the requisite thickness of plaster, after which, when it has hardened, take off the medal and oil the tin-foil surface, over which the plaster is again poured. When the latter thickness of plaster has hardened, they may be separated and the foil taken off.
Should the medal have under-cut parts which interfere with a direct separation, then use glue instead of plaster, and the moulds may be forcibly withdrawn without materially damaging them. Any other flat object may be treated as above described. See GLUE-MOULDS.
Melting a Small Quantity of Iron.--See FONDERIE A CALABASSE.