Britannia Metal.

Britannia Metal. The composition of Britannia metal varies. Much of it is 90 tin, 8 antimony, and 2 copper. Another formula is 81 tin, 16 antimony, 1 copper, and 2 zinc. But most of the alloys passing under this name have between 80 and 90 per cent. of tin with varying proportions of antimony and copper. The manufacture was begun at Sheffield by Hancock and Jessop in 1770; it reached Birmingham towards the close of the century, and made gradual progress. At first, the articles were made by stamping with dies, and soldering up into form; this, being a slow operation, rendered the articles expensive. Afterwards, the curious process of metal-spinning was introduced; and this, with the subsidiary operation of swaging, rendered a great reduction in price possible. In the spinning process, a thin sheet or piece of Britannia metal is placed upon a wooden model shaped like the article to be made; the model is made to rotate in a lathe; and steel, hardwood, bloodstone, or other tools are employed to press the yielding metal into all the curvatures of the model. Ductility is an essential quality to the attainment of this end with the metal; how complete it is, may be seen in such articles as Britannia metal teapots and dish-covers, the principal forms of which are not given by hammering, stamping, or casting, but by spinning. Besides spinning and swaging, the processes include stamping, soldering, casting, and polishing. Britannia metal forms a good ground or basis for electroplating with silver. Britannia metal spoons and ladles, made by casting, stamping, and burnishing, have been nearly driven out of the market by German silver; but the former metal is more largely used than ever for hot-water jugs, coffee-pots, sugar-basins, soup tureens, gravy-dishes, vegetable and side dishes, dram bottles, drinking-cups, wine-coolers, soap-boxes, liquor-frames, cruets, waiters, trays, &c.; and as a basis for electroplate. Sheffield and Birmingham are the chief seats of the manufacture. After electroplating came into general use in the decade 1840-50, the trade in Britannia metal wares became double what it was previously.