Page:Cyclopedia of Painting-Armstrong, George D (1908).djvu/429

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USEFUL INFORMATION
421

of lead, at a temperature of from 95° to 120° Fahrenheit, and in this latter the wood is allowed to remain from thirty to fifty hours. After being subjected to a thorough drying, it is in a condition for being polished with lead, tin, or zinc, as may be desired, finishing the process with a burnisher of either glass or porcelain, the appearance of the wood being in every respect that of polished metal, having, in fact, the semblance of a polished mirror, which is unaffected by moisture.

Moulding Composition. A composition for making good some slight portion of a defective moulding is made of powdered whiting with glue in solution worked into a paste, with a sufficiency of turpentine to destroy the brittleness, a little linseed oil may be added to prevent stickiness. The composition may be colored to suit the surroundings.

Moulding Wax. To prepare wax for taking moulds, put some common beeswax into an earthenware pot, place it over a slow fire, and when it is all melted stir into it a little white lead or plumbago, about 1 ounce of the lead to 1 pound of the wax. This mixture tends to prevent the mould from cracking when cooling, and from floating in the solution. It should be re-melted two or three times before using for the first time. Another kind is made thus: Melt carefully over a moderate fire 2 pounds of yellow beeswax, add 4+12 pounds of Venice turpentine, 2 ounces of lard, 1+34 pounds of purified bole, and mix thoroughly. Then gradually pour the mixture into a vessel containing water, and thoroughly knead several times with the hands. The wax should be melted at such a low temperature that no bubbles appear upon the melted surface.

Paint for Iron. The following are anticorrosive paints for iron: Take 10 per cent, of burnt magnesia, or even baryta or strontia, and mix it cold with ordinary linseed oil paint, and then enough mineral oil to envelope the alkaline earth, the free acid of the paint will be neutral-