2166. Cement for Glass Syringes

2166.     Cement for Glass Syringes. Take resin, 2 parts; gutta percha, 1 part; melt together over a slow fire, apply hot, and trim with a hot knife.

2167. Quickly-Setting Rust Joint Cement

2167.      Quickly-Setting Rust Joint Cement. Make into a paste with water 1 part by weight sal ammoniac in powder, 2 parts flower of sulphur, and 80 parts iron borings.

2168. Slowly-Setting Rust Joint Cement

2168.    Slowly-Setting Rust Joint Cement. Make into a paste with water, 2 parts sal ammoniac, 1 part flower of sulphur, and 200 parts iron borings. This cement is better than the last if the joint is not required for immediate use.

2169. Red Lead Cement for Face Joints

2169.     Red Lead Cement for Face Joints. Mix 1 part each white and red lead with linseed oil to the proper consistence.

2170. Singer's Cement for Electrical Machines and Galvanic Troughs

2170.    Singer's Cement for Electrical Machines and Galvanic Troughs. Melt together 5 pounds resin, and 1 pound bees' wax, and stir in 1 pound red ochre (highly dried, and still "warm), with 4 ounces Paris plaster, continuing the heat a little above 212° and stirring constantly till all frothing ceases. Or, (for troughs), resin, 6 pounds; dried red ochre, 1 pound; calcined plaster of Paris, 1/2 pound; linseed oil, 1/4 pound.

2171. Cement for Rooms

2171. Cement for Rooms. M. Sarel, of Paris, has made an invention which is pronounced better than plaster of Paris for coating the walls and ceilings of rooms. A coat of oxide of zinc, mixed with size, made up like a wash, is first laid on, and over that a coat of chloride of zinc applied, prepared in the same way as the first wash. The oxide and chloride effect an immediate combination, and form a kind of cement, smooth and polished as glass, and possessing the advantages of oil paint without its disadvantages of smell.

2172. Coppersmith's or Blood Cement

2172.     Coppersmith's or Blood Cement. Bullock's blood thickened with finely powdered quicklime makes a good cement to secure the edges and rivets of copper boilers, to mend leaks from joints, etc.. It must be used as soon as mixed, as it rapidly gets hard. It is extremely cheap and very durable, and is suited for many purposes where a strong cement is required.

2173. Pew's Composition for Covering Buildings

2173.    Pew's Composition for Covering Buildings. Take the hardest and purest limestone (white marble is to be preferred), free from sand, clay, or other matter; calcine it in a reverberatory furnace, pulverize, and pass it through a sieve. 1 part, by weight, is to be mixed with 2 parts clay well baked and similarly pulverized, conducting the whole operation with great care. This forms the first powder. The second is to be made of 1 part calcined and pulverized gypsum, to which is added 2 parts clay, baked and pulverized. These two powders are to be combined, and intimately incorporated, so as to form a perfect mixture. When it is to be used, mix it with about a fourth part of its weight of water, added gradually, stirring the mass well the whole time, until it forms a thick paste, in which state it is to be spread like mortar upon the desired surface. It becomes in time as hard as stone, allows no moisture to penetrate, and is not cracked by heat. When well prepared it will last any length of time. When in its plastic or soft state, it may be colored of any desired tint.