Dissolve 30 grs. of sulphate of aluminum in two thirds of an ounce of water, and add it to 8 1/2 fluid ounces of a strong solution of gum arabic. Botany Bay Cement. Botany Bay gum, melted and mixed with an equal quantity of brickdust. Cap Cement. As Singer's; but 1 lb. of dried Venetian red may be substituted for the red ochre and Paris plaster. Bottle Cement. Resin 15 parts, tallow 4 (or wax 3) parts, highly dried red ochre 6 parts, or ivory black q. s. The common kinds of sealing wax are also used. Turner's Cement. Bee's-wax 1 oz., resin 1/2 oz., pitch 1/2 oz.

Melt, and stir in fine brickdust q. s. Coppersmith's Cement. Powdered quicklime, mixed with bullock's blood, and applied immediately. Engineers' Cement. Equal weights of red and white lead, with drying oil, spread on tow, or canvas. For metallic joints, or to unite large stones, in cisterns, etc. Cement for Steam Pipes. Good linseed oil, varnish ground with equal weights of white lead, oxide of manganese, and pipe-clay. Iron Cement, for closing the joints of iron pipes. Iron borings, coarsely powdered, 5 lbs., powdered sal ammoniac 2 oz., sulphur 1 oz., water sufficient to moisten it. It quickly hardens; but if time can be allowed, it sets more firmly without the sulphur. It must be used as soon as mixed, and rammed tightly into the joints.