Manufacturer and builder 9, syyskuu 1871
[182] Artificial Shellac.
Take natural India rubber, clean it and cut it in pieces, and soften it by boiling in water; put it under water in very thin scraps, and dry it; then take common resin 20 parts, melt it, and bring in slowly 14 to 15 parts of the India rubber scraps, till they are all dissolved: stir it till cold, and you have a mass, in its physical propertied, very similar to shellac.
[201] Coloring Billiard-Balls.
Billiard-balls may be colored red by first steeping in a mordant of nitro-hydrochlorate of tin, and then plunging them in a hot decoction of Brazil or cochineal; afterwards placing them in cold water. Experiments will teach the proportions which influence the shade of color. Tin mordant - Mix four ounces hydrochloric with one of nitric acid and one of water; dissolve in it, by small portions at a time, two drachms of grain.
[207] Improved White Paint.
The cause of the yellow color which white-lead soon shows when used inside, and not kept bleached by the action of the open air, is the oil. Keep the oil out, and the principal cause of the change of the white into yellow is removed; but we should advise to take zinc-white for inside work, mix it with turpentine alone, and when dry put on a copal or damar varnish, made of the lac with turpentine. In Europe, there is a beautiful transparent varnish made called porcelain varnish, which, when applied under the circumstances mentioned, gives the most beautiful gloss, and remains white. It is nothing but a very pure copal and turpentine varnish.
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