For a cement which will attach tinfoil to paper or other articles, dissolve caustic soda in twice its weight of water; add rye flour until no more of the flour will dissolve, adding a little water and stirring all the time. To the paste thus prepared add a few drops of Venice turpentine, liquefying the turpentine by gentle heat. The paste thus made will firmly fix tinfoil.
A cement for joining cast-iron water pipes is made as follows: Intimately mix 8 parts white lead, 2 parts litharge, 1 part of colophony and 24 parts Roman cement. Stir this into a plastic mass with old linseed oil, kept boiling together with one-half its weight of colophony until the dissolution of the latter.
(2) Melt together tallow and colophony, stirring into the melted mass sufficient finely sifted gypsum to give it the consistency desired. Compound together equal parts of potters' clay, Roman cement, clay and burned lime, all dried separately and ground fine. The mixture is to be worked together with linseed oil.
An inexpensive cement for uniting zinc with glass may be made as follows: One pound of shellac dissolved in 1 pint of alcohol, with one-twentieth its volume of a. solution of gutta-percha in bisulphide of carbon, will dry quickly. A slow-drying one may be made thus: Two ounces of thick glue solution, 1 ounce linseed oil varnish, or 3/4 ounce Venetian turpentine. Boil together.
(2) A cement to unite zinc strongly to glass is thus made: One pound of shellac dissolved in one pint of alcohol, with one-twentieth its volume of a solution of gutta-percha in bisulphide of carbon. It dries quickly.
A colored cement to repair zinc ornaments is made by thoroughly stirring together fine whiting with soda water solution of 33 degrees Be, to which zinc dust is added, the whole being stirred to a thick, plastic-mass, which hardens in from six to eight hours and acquires an unusual calidity and a gray color. If it is desired that it should have a lustrous white color after hardening it can be polished with an agate.
Gasfitters' cement consists of 4 1/2 parts of resin, 1 part of wax, and 3 parts of Venitian red.
Is composed of tin (2 parts), lead (3 parts), bismuth (2 1/2 parts).
Grouvelles' oil cement is made by intimately mixing 2 1/2 parts of white lead, 1 part of red lead, 2 parts of perfectly dry clay, finely pulverized with boiled linseed oil.
A cement impervious to oil, and, therefore, useful to mend kerosene lamps, is made by taking 3 parts of resin boiled with 5 parts of water and 1 part of caustic soda. Mix with half its weight of plaster of paris. This sets in one hour.
Puscher recommends a resin soap for this purpose, made by boiling 1 part caustic soda, 3 parts of colo-phonium (resin) in 5 parts of water, and kneading into it half the quantity of plaster of paris. This cement is useful for fastening the brass top on glass lamps, as it is very strong, is not acted upon by petroleum, bears heat very well, and hardens in one-half or three-quarters of an hour.
By substituting zinc white, white lead, or air-slaked lime for plaster of paris, it hardens more slowly. Water only attacks the surface of this cement.
Wiederhold recommends, for the same purpose, a fusible metal, composed of 4 parts lead, 2 parts tin. and 2 1/2 parts bismuth, which melts at 212 degrees Fahrenheit. The melted metal is poured into the capsule, the glass pressed into it, and then allowed to cool slowly in a warm place.