2211. Pollack's Cement for Iron and Stone

2211.    Pollack's Cement for Iron and Stone. This cement takes some little time to dry, but turns almost as hard as stone, and is fire and water-proof. For mending cracks in stone or cast-iron ware, where iron filings cannot be had, it is invaluable. Take litharge and red lead, equal parts, mix thoroughly and make into a paste with concentrated glycerine to the consistency of soft putty; fill the crack and smear a thin layer on both sides of the casting so as to completely cover the fracture. This layer can be rubbed off if necessary when nearly dry by an old knife or chisel. M. Pollack has used it to fasten the different portions of a fly-wheel with great success; while, when placed between stones, and once hardened, it is easier to break the stone than the joint.

2212. Cement from Furnace Slag

2212.     Cement from Furnace Slag. Furnace slag can be made to furnish an excellent cement by selecting such portions of it as are readily dissolved in dilute hydrochloric acid. On subjecting it to the action of the acid, silica is thrown down, which is afterward to be washed, dried, and pulverized. One part of this is next to be mixed with 9 parts powdered slag and the necessary quantity of slacked lime. This matter soon hardens, and rivals the best cement in its durability.

2213. Zeiodite

2213.    Zeiodite. This substance is made by mixing 20 to 30 parts roll sulphur with 24 parts powdered glue or pumice, which forms a mass as hard as stone that resists the action of water and the strongest acids. Prof. R. Boettger recommends it, therefore, for making water-tight and air-tight cells for galvanic batteries.

2214. Cement for Closing Cracks in Stoves, etc

2214.    Cement for Closing Cracks in Stoves, etc. A useful cement for closing up cracks in stove plates, stove doors, etc., is prepared by mixing finely-pulverized iron, such as can be procured at the druggists, with liquid water-glass, to a thick paste, and then coating the cracks with it. The hotter the fire then becomes, the more does the cement melt and combine with its metallic ingredients, and the more completely will the crack become closed.

2215. Cement for Fastening Iron to Stone

2215.    Cement for Fastening Iron to Stone. A cement for fastening iron to stone, which becomes nearly as hard as the stone itself, consists of 6 parts Portland cement, 1 part powdered lime, not slacked, 2 parts sand, and 1 part slacked lime, mixed with water to the proper consistency, the stone and iron both being previously dampened. In 48 hours it will have set firmly.

2216. Strong Cement for Iron

2216.     Strong Cement for Iron. To 4 or 5 parts clay, thoroughly dried and pulverized, add 2 parts iron filings free from oxide, 1 part peroxide of manganese, 1/2 part of sea salt, and 1/2 part borax. Mingle thoroughly, and render as fine as possible; then reduce to a thick paste with the necessary quantity of water, mixing thoroughly. It must be used immediately. After application, it should be exposed to warmth, gradually increasing almost to white heat. This cement is very hard, and presents complete resistance alike to a red heat and boiling water.