2. The rolled sheets are purchased according to weight by the coppersmith, who employs them in sheathing the bottoms of ships, in covering the roofs of houses, and in constructing steam-boilers and stills. He also fabricates them into a variety of household utensils, although the use of this metal in preparing and preserving food, is attended with some danger, on account of the poisonous quality of the verdigris which is produced on the surface.
3. An attempt has been made to obviate this difficulty, by lining the vessels with a thin coating of tin. This answers the purpose fully, so long as the covering of tin remains entire. But, in cases of exposure to heat, it is liable to be melted off, unless it is kept covered with water.
4. This metal can be reduced by forging to any shape; but, during the process, it will bear no heat greater than a red heat; and, as it does not admit of welding, like iron, different pieces are united with bolts, or rivets, of the same metal, as in the case of the larger kinds of vessels, or by means of solder made of brass and zinc, or zinc and lead, as in the case of those of smaller dimensions.
5. Brass is applied to a greater variety of purposes in the arts than copper. This preference has arisen from its superior beauty, from the greater facility with which it can be formed into any required shape, and from its being less influenced by exposure to the ordinary chemical agents.
6. Some of the articles manufactured of brass, are forged to the required form, and others are made of rolled sheets; but, in most cases, they pass through the hands of the brass-founder, who liquifies the metal, and pours it into moulds of sand. For the sake of lightness, and economy of material, many articles are made hollow; in such cases, they are cast in halves or pieces, and these are afterwards soldered together.
7. Pieces which have been cast are generally reduced in size, and brought more exactly to the proposed form, either in a lathe, with tools adapted to turning, or in the vice, with files and other suitable instruments. The operators in brass form a class of mechanics distinct from those who work in copper.
THE BUTTON-MAKER.
1. Trifling as the manufacture of buttons may appear, there are few which include a greater variety of operations. The number of substances of which they are made is very great, among which are gold, silver, various alloys of copper, steel, tin, glass, mother-of-pearl, bone, horn, and tortoise-shell, besides those which consist of moulds of wood or bone, covered with silk, mohair, or similar materials.
2. In making gilt buttons, the blanks, or bodies, are cut from rolled plates of brass, with a circular punch driven by means of a fly wheel. The blanks thus produced, are planished with a plain die, if they are intended for plain buttons; or with one having on it an engraved figure, if they are to be of the ornamental kind. In either case, the die is usually driven with a fly press.
3. The shanks are next placed on one side of the proposed button, and held there temporarily with a wire clasp. A small quantity of solder and rosin having been applied to each shank, the buttons are exposed to heat on an iron plate, until the solder shall have melted. The shanks having been thus firmly soldered on, the buttons are turned off smoothly on their edges in a lathe.