This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.
An easy method of removing grease spots consists in immersing the separable parts for several hours in a warm lye, heated to about 70° C. (158° F.), said lye to be made of 9 parts of caustic soda and 180 parts of water. These pieces, together with the fixed parts of the stove, may be well brushed with this lye and afterwards rinsed in clean, warm water. The grease will be dissolved, and the stove restored almost to its original state.
Make rotten stone into a stiff, paste with soft soap and water. Rub on with a woolen rag, and polish with dry whiting and rotten stone. Finish with a leather and dry whiting. Many of the substances and mixtures used to clean brass will effectively clean copper. Oxalic acid is said to be the best medium for cleaning copper, but after using it the surface of the copper must be well washed, dried, and then rubbed with sweet oil and tripoli, or some other polishing agent. Otherwise the metal will soon tarnish again.
The rust must first be thoroughly removed with a steel-wire brush. When this is done apply one or two coats of red lead or graphite paint. After this priming has become hard, paint with double-burnt lampblack and equal parts of oil of turpentine and varnish. This coating is followed by one of lampblack ground with coach varnish. Now paint the sin-
gle portions with "mixtion" (gilding oil) and gild as usual. Such crosses look better when they are not altogether black. Ornaments may be very well treated in colors with oil paint and then varnished. The crosses treated in this manner are preserved for many years, but it is essential to use good exterior or coach varnish for varnishing, and not the so-called black varnish, which is mostly composed of asphalt or tar.
The brown film which forms on low-quality gold articles is removed by coating with fuming hydrochloric acid, whereupon they are brushed off with Vienna lime and petroleum. Finally, clean the objects with benzine, rinse again in pure benzine, and dry in sawdust.
Clean the bronze with soft soap; next wash it in plenty of water; wipe, let dry, and apply light encaustic mixture composed of spirit of turpentine in which a small quantity of yellow wax has been dissolved. The encaustic is spread by means of a linen or woolen wad. For gilt bronze, add 1 spoonful of alkali to 3 spoonfuls of water and rub the article with this by means of a ball of wadding. Next wipe with a clean chamois, similar to that employed in silvering.