Читать книгу A Manual of Mending and Repairing; With Diagrams онлайн

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A common cement for mending broken glass or china is prepared as follows:—To two parts of gum-shellac add one of turpentine; boil them over a slow fire, and form the mass into small cakes before it dries. To use it, warm with a lamp. To mend ivory or wood, take a cake and let it dissolve in spirits of wine.

A very strong cement is made as follows:—Take one ounce of finely powdered mastic dissolved in six of spirits of wine and two ounces of shredded sturgeon’s bladder dissolved in two ounces common spirits; add one half ounce of gum-ammoniac as it hardens; warm it when it is to be used. This is as strong a cement as can be made.

Defects, cracks, and repairs in porcelain, &c., may often be concealed as follows:—Paint the spot with silicate of soda, not too much thinned, and dust it over before it dries with bronze powder. This will set so hard that it may be polished with an agate burnisher.

It is also possible that many of my readers have heard of gesso painting, an art perfected by Mr. Walter Crane. This consists of painting with plaster of Paris in solution, with the point of a brush, depositing the soft paste in relief. The same principle is applicable to painting in silicate and whiting on glass surfaces. By means of it decoration can be given to any glass bottle or other object.