When the model is thus completed, and surrounded by the mould, it is lowered down into a pit, by means of a crane, and a brick wall, capable of resisting consi derable pressure, built around it. There it is exposed to a moderate degree of heat, by which the waxen coat ing is melted from within the mould, and runs off by con duits, but, at the same time, leaves the interior surface corresponding with the outline which it occupied. For a statue larger than life, two days and nights are required for the operation, daring which time it is necessary that the heat be moderate, otherwise the wax might boil up against the mould and injure it, though the varnish contributed to render it smooth and equal. It is like wise necessary that the pit be somewhat deeper than the height of the figure, in order that the metal may rise above it, and avoid the imperfections which would other wise arise.
All the previous preparations being completed, a brisk fire is kept up in the furnace, and the metal reduced to a state of perfect fusion, the channel of communication is opened, and it begins to flow. The numerous conduits introduce it to the interior or the mould, and the space before occupied by the wax is speedily filled. After the
cast has stood a day or two to cool, the mould is taken off, and it is elevated from the pit by a crane, when it appears altogether covered by spines. These are the metal which filled the channels of communication; and by their removal, and the subsequent polish, the work is brought to perfection.
It has been maintained, that the ancients were such masters of this branch of casting, that they could take figures from the mould free of spines, and so clean and perfect, as not to require finishing by the chisel or the file. But this has been denied by the most intelli gent among the moderns, and certainly it would be grant ing the artist a wonderful degree of skill to suppose it the case.
Casts of all different shapes and sizes may be obtained by practising this method in detail. Some statues weigh one or two thousand pounds or more, according to the size and thickness of the metal. One of Louis XIV. at Paris, weighing above 60,000 pounds, was obtained from a single mass of fused metal which flowed fifty feet be tween the furnace and the mould. See Dossie's Hand maid to the Arts; and Benvenuto Cellini Due Trattati dove veggono Infiniti segreti nel Gettare le Figure di Bronzo. (c)