THE TINMAN.

WORKSHOP.

Tin is never found existing in an uncombined or native state. Tin ore occurs most abundantly in Cornwall and Devon, the mines of these counties having been celebrated for this metal from very ancient times. The district in Cornwall where tin mines are most abundant is termed the“Stannaries.” The Prince of Wales for the time being derives a large income from the mines, and is termed Lord Warden of the Stannaries. The word “Stannaries” is derived from the Latinstannum, tin. The amount of tin ore annually obtained from the Cornwall and Devon mines amounts to 11,000 tons, which, at the average value of £63 per ton, is worth £693,000. This ore yields about 7,000 tons of the metal, having an average value of £119 per ton. About four-fifths of all the tin raised in the world is produced in these mines. The ore is a heavy, hard, brittle, and usually dark brown mineral, which occurs chiefly in granular masses of various sizes. These grains are obtained in mines, where they occur in veins mixed with other minerals, and also from the beds of streams, where they have been washed out of the soil by the action of running water. In the former case they are termed tin stone; in the latter stream-tin.

Tin is obtained from the ore by first breaking up the latter, whilst a current of water flows over it and carries off the impurities, which are lighter, and therefore more readily borne away than the heavier tin ore. After being thus freed from the admixture of other minerals, the ore is usually roasted or burned, to drive off any traces of sulphur it may contain; it is afterwards heated to redness with blind coal or culm, and a small portion of lime, when the melted metal separates from the dross, and runs into cavities prepared for its reception. It is afterwards refined by being remelted, and other impurities separated, which either sink or float on the surface. The purest metal is yielded by the ore called stream-tin, which is smelted with charcoal instead of coal. If a block of tin thus obtained is heated slightly, and then allowed to fall from a height, it separates into a numberof prisms which adhere together in pyramidal masses. In this state it is termed grain-tin. Tin is a silvery-white metal possessed of a high degree of metallic lustre. It is sufficiently soft to be cut with a knife, and may be readily bent, when it gives out a peculiar crackling noise; if repeatedly bent and straightened, it becomes hot from the friction of its particles with one another, and ultimately breaks. It is inelastic and moderately ductile, but very malleable, the thickness of tin-foil being about one thousandth part of an inch. It has but little tenacity, a wire of one-tenth of an inch in diameter not being able to support a heavier weight than 49 lbs.

Tin is the most easily melted of all the common metals, and it possesses the valuable property of not rusting when exposed at ordinary temperatures to the conjoined action of air and water, or even to weak vegetable acids. Tin, in a pure state, is seldom employed; but in combination with other metals it is a substance of great value. Its most important uses depend on its power of resisting the action of air and moisture; it is therefore largely employed for protecting the surfaces of copper and iron, that rust so readily.

Tin plate, or more properly tinned plate, which is so largely employed in the manufacture of saucepans, coffee-pots, tea-kettles, &c. by the tinman is not, as its ordinary name seems to imply, made of tin, but is formed of the best sheet iron, rolled out to the required thickness, and coated on each side with a layer of tin. Copper vessels ought to be invariably tinned inside, to prevent the rusting of the copper by the action of acids. Tinfoil is largely employed for the purpose of preserving moist articles from becoming dry, and is used instead of paper for enclosingfancy soap, chocolate, and other substances of a similar nature. It is also extensively used in the manufacture of looking-glasses, and is sometimes placed behind paper-hangings to exclude the damp of the walls. The most important alloys into the composition of which tin enters are bronze, pewter, bell-metal, and solder. Tin dissolved in acids is largely employed by dyers in fixing or rendering permanent various colours used in dyeing. The preparation termed putty powder is a rust of tin, obtained by exposing the melted metal to the air; it is employed in polishing metals and other articles.

Mallet. Soldering Iron. Hammer. Block Hammer.

The tinning of the inner surfaces of cooking utensils and other vessels of capacity is effected by scouring the surface until it is perfectly bright and clean; then heating the vessel, pouring in some melted tin and rolling it about, and rubbing the tin all over the surface with a piece of cloth or a handful of tow; powdered rosin is used to prevent the formation of oxide. Bridle bits, stirrups, and many other small articles, are tinned by immersing them in fluid tin. Tin-plate working, or the forming sheets of tinned iron into a variety of useful vessels and utensils, is carried onby means of bench and handshears,mallets, andhammers,steel headsandwooden blocks,soldering ironsandswages. In the formation of a vessel, the first operation is to cut the plate to the proper size and form with shears, and, when the dimensions of the article require it, to join them together, which is done either by simply laying the edge of one plate over that of the other, and then soldering them together, or by folding the edges together with laps and then soldering them. Similar joints are required when gores or other pieces are to be inserted, and also at the junction by which a cylinder is closed in. The usual method of forming laps, bends, or folds, for this or other purposes, is to lay the plate over the edge of the bench and to bend it by repeated strokes with a hammer; but a machine is sometimes used for this purpose.

Straight Snips. Scotch Snips. Large Shears. Bent Snips.

After a tin vessel has been rounded upon a block ormandril by striking it with a wooden mallet, and the seams finished, all its exterior edges are strengthened by bending a thick iron wire into the proper form, applying it to what would otherwise be the raw edges of the metal, and dexterously folding them over it with a hammer.

Two-handed Wrench. Soldering Pile. Pudding Stake. Punches. Hatchet Stake. Tongs.

A superior kind of tin ware, commonly known as block tin ware, is carefully finished by beating or planishing with a polished steel hammer upon ametal stake. The process of swaging is resorted to as a ready means of producing grooved or ridged borders, or other embossed ornaments. This process consists in striking the metal between two steel dies or swages, the faces of which bear the desired pattern, and are made counterparts of each other. Manyornamental articles are produced by embossing or stamping tin plate, in the same manner as other metallic sheets, with a fly-press or other machinery. Cheap coffin-plates are manufactured at Birmingham in this way; and these and similar articles are sometimes lacquered, painted, or japanned. Tin forms the principal ingredients in various kinds of pewter and other white-metal alloys, which are manufactured into domestic utensils by casting, stamping, and other processes.

Chisels. Charcoal Stove. Polishing Anvil.

Britannia metal is a mixture of tin, antimony, copper, and brass, which is melted, cast into slabs, and rolled into sheets. The principal use of this metal is for candlesticks, teapots, coffee-biggins, and other vessels for containing liquids. The feet of candlesticks, the bodies of teapots, and other articles containing embossed work, are stampedbetween dies; while articles of a more globular shape are stamped in two or more pieces, and afterwards soldered together. The sheet metal has a ductility which enables it to be bent into various curved forms by pressure on a model or core: this process is calledspinning.

Funnel Stake. Punches. Horse. Punches. Bick Irons. Crease Iron.

Many small vessels, spoons, and other articles, are cast in an alloy somewhat harder than that which is rolled into sheets. Most of the tools employed by the Tinman are theirons,stakes, andbickers, on which the tin is hammered into proper shape, withshearsfor cutting, thepunchesfor piercing holes, and thesoldering ironandcharcoal stovefor making joints.

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