THE COPPERSMITH.

WORKSHOP.

The very great variety of purposes for which the metal called copper is used, renders it one of the most valuable productions of this country, and several very important manufactures would be incomplete without it, since it is the principal material of which many large vessels are formed, and is also largely employed as an alloy for other metals. Although the metal is sometimes found in a pure or native state, its most abundant ore is that known as copper pyrites, of which there are many kinds. The mostcommon yellow copper ore is a very abundant mineral, found in large quantities in Cornwall, Devon, and the Isle of Anglesea, and is a compound of about equal parts of copper, iron, and sulphur. The mines of Devon and Cornwall yield more than three-fourths of the copper obtained in England, or about 190,000 tons of ore in a year, the value of which is above a million sterling. The amount of copper annually obtained in the United Kingdom is about 15,000 tons, worth more than a million and a half of money. About the same quantity is imported into this country from Chili and Cuba, and a very valuable copper ore is also found at the Burra Burra mines in Australia.

The copper ores of Cornwall and other parts of the country are generally shipped to Swansea, where coal is abundant, in order to be separated from the metal. For this purpose the ore is heated to redness, or roasted in an open furnace, in order to burn away the sulphur, and the fumes given out by this process are most pernicious. The ore is afterwards melted several times to separate the other impurities, which, when fused, float like scum on the surface of the liquid metal, and are then easily removed.

Copper has a peculiar reddish colour, and will bear a brilliant polish; its smell and taste are both disagreeable. It is one of the most malleable of metals, and can be so readily worked by the hammer that it is beaten out into thin leaves, which, under the name of “Dutch metal,” are employed in ornamenting toys, &c. in imitation of gilding.

It is also so ductile that it can be drawn out into finer wires than any ordinary metal, except gold, silver, and iron, and its tenacity is so great that a wire one-tenth of an inch in diameter will bear a weight of 175 lbs. This wire is very flexible, and not very elastic, but when rolled intosheets copper is one of the most elastic, and when struck one of the most vibratory and loud sounding metals.

If taken into the animal system all preparations of copper are violent poisons; and, as this metal is directly acted upon by vinegar and other acids, it should not be employed for making vessels used in cooking or preparing food.

The easy malleability of copper allows it to be rolled into thin sheets, which can easily be hammered into any form that may be desired, and it is this operation which belongs to the trade of the Coppersmith.

Sheet copper is employed in covering the bottoms of ships, to protect them from the attacks of marine animals; it is also used for coins, which are punched out of the sheet of metal and stamped with dies, and for plates on which pictures are engraved; the metal being soft enough to yield to the tool of the engraver, but yet sufficiently hard to resist the pressure necessary to print the picture.

As an ingredient in alloys copper is most valuable, especially in bell metal, which is composed of three parts of copper and one part of tin; in bronze, which is nine-tenths copper and one-tenth tin; and in German silver, argentine, nickel silver, and other alloys used for making forks, spoons, dishes, &c. which are composed of copper, zinc, and nickel. These are very beautiful alloys, closely resembling silver; but the copper they contain is liable to be partially dissolved by any long exposure to the action of acids.

Copper is used in small quantities as an alloy for gold and silver both in coinage and in plate, to give the requisite degree of hardness. Gold used for coins, or what is called standard gold, is formed of eleven parts of pure gold and one part of copper. Being a better conductor of electricity than any other metal, it is largely employed in the formationof telegraphic wires; and, as it is not hard enough to strike fire with flint or grit, it is used in gunpowder mills and magazines instead of iron.

The processes of casting and rolling copper into sheets are so much like those already described in the manufacture of iron that they need not be repeated, but the trade of the Coppersmith is distinct from those of the workers in other metals, though they mostly consist in forming the sheet copper into various shapes and utensils by means ofhammers, of which thesmoothing hammer, theset hammer, and theriveting hammer, explain their own uses by their names.

Copper Bit. Oval Wedge. Riveting Hammer. Smoothing Hammer. Cob Hammer. Set Hammer.

In manufacturing the large vessels with circular bottoms which are so frequently made of copper, the metal is first cast in a shape resembling a round spectacle glass, that is to say, a flat cake, thick in the middle and gradually diminishing in thickness towards the edge. It is thensubjected to the powerful blows of a tilt hammer, the beating being principally confined to the centre. The effect of this is not only to reduce the thickness of the copper, but to cause the disc to turn up at the edges and assume the form of a hollow dish.

Punches. Hand Vice. Cutting Punch. Spanner. Anvil. Shears for Sheet Copper. Hand Shears.

Another operation of the Coppersmith is calledplanishing, or hammering the metal until it becomes more dense, firm,and tough; any one who looks at the surface of a large copper vessel will see the marks of the hammer by which it has been planished.

It is by the combined operation of casting, rolling, hammering, and planishing, as well as by the processes of fastening, either withrivetsor withsolder, that nearly all copper articles are made.

Plumber’s Iron. Iron Horse. Pouncing Block and Hammer.

Of the tools used by the Coppersmith, beside those already mentioned, the principal arepunchesfor cutting or piercing holes,shearsfor cutting the sheets of metal, thespannerfor turning heads of screws or nuts, theanvil, theblocksandhorsesfor receiving the work in such a position as to operate on any part where the hammer or the punch is required, and theironfor soldering. There are five different modes of forming copper piping out of sheet metal; in the first the edges of the sheet, which is curved round a mandril, are made to meet without overlapping,and are joined with hard solder; in the second they overlap and are united by soft solder; in the third they overlap and are secured by rivets; in the fourth the edges are folded one over the other, and are made close and firm by hammering; and in the fifth both edges of the pipe are turned back and covered with a strip of sheet metal, the two edges of which are turned in and hammered down.

Wood Horse.

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