To make metal pipes, bend a piece of soft steel to a pipe so that both edges lie close together, then polish same and coat with copper in a suitable cyanide solution. If a layer of copper of special thickness is desired it should be treated in a solution of cupric sulphate. Then coat the pipe with brass in a cyanide solution and then polish. This system will give a metallic-coated pipe, without any soldering or welding.
To secure the effect of marble on zinc, moisten the gray zinc and apply hydro-chloric acid in spots with a sponge, then rinse off, and while still wet pour over it an acidified solution of sulphate of copper, which will produce the appearance of black marble. This having a dull surface should undergo a coat of varnish.
To make matches, take 8 parts (by weight) gum arabic, 5 parts phosphorus, 7 parts nitre, 8 parts powdered peroxide of manganese. Make a mucilage of the gum and water, then add the manganese, then the phosphorus, and heat them to about 130 degrees Fahrenheit. When the phosphorus is melted add the nitre, and stir the whole thoroughly until the mass becomes a uniform paste. The matches, the ends of which have been previously dipped in sulphur, are then dipped in the composition and dried in the air. Friction papers for the pocket or matches for parlor and bedroom use may be made by adding some gum benzoin to the mucilage, which will give an agreeable odor when the matches are ignited.
Gutta percha is readily dissolved in boiling spirits of turpentine, or in coal tar or naphtha. Practically, it cannot be melted. For all mechanical purposes it is shaved to a thin consistency, then thrown into a steam-heated tank or vessel, where it is rendered soft. The mass is then transferred into a sort of mangling machine, which tears it into shreds, then it is softened to a dough-like consistency by being immersed in hot water, after which it is kneaded in heated hollow cylinders which revolve and mix the plastic mass and give to it a uniform pasty consistency. It is then passed through heated rollers, coming out much like rolled pie-crust, when it can be worked into any desired form, and is afterwards hardened by being slowly dried before a proper heat.
To mend a file have a little bottle of muriate of zinc and wet the break with it immediately; then heat a soldering iron and tin the ends of the file. Heat the file pretty warm - not enough to start the temper, but rather too hot to hold in the hand. When well tinned and hot, press the two pieces firmly together, squeeze out nearly all the solder, and let the file cool. Trim off the joint. Let it lay a day or two, or, in damp weather, even an hour or two, and you can never mend it so it will stay. Take it the minute it snaps and you can mend it.
To mend granite ironware, place the article to be mended upon a piece of iron, so that it will be perfectly solid, and pound the rivet down flat, being careful to strike only the rivet, as a blow on the granite ware would cause the enamel to cleave off.
(2) Place the article to be repaired on something firm and with a chisel or other tool peck off about one-quarter of an inch around the hole. Scrape with a knife or scraper until bright. Flux with moderately strong acid and solder all the bright space the granite has been broken from.