1851 Great Exhibition: Official Catalogue: Class VIII.: Henry Hart
245. HART, HENRY, 54 New Canal Street, Birmingham — Manufacturer.
Pair of highly-finished double-barrel guns.
Double- barrel gun, pistol hand-stock; gamekeeper's gun.
Single gun, pistol hand highly finished, with raised top rib.
Small pistol-hand double gun.
Small single gun. — All (above) with stub-twist barrels.
Specimens of gun-barrel manufacture in every state, from the old horse-nail stubs of the earliest period to the latest improvements.
[The serious accidents arising from the bursting of gun-barrels have led manufacturers to seek the means of preventing their recurrence as far as possible; fibres of iron strictly parallel would fail to impart the necessary strength, as also would iron if of a uniform crystalline composition. A better construction of material has been found in the welding together portions of iron and steel; these become interlaced in the various processes of hammering from the bundle of iron and steel called the "bloom," until the barrel passes finished from the hands of the forger. The twisted appearance which is observed on the best barrels, even after the rich brown stain is removed, arises from the ribbon-like form which the "bloom," after being drawn into a strip, takes when wound spirally round a mandril previous to welding; these are known as Damascus barrels. Barrels of a more common kind are produced from "blooms" made exclusively of stub-nails, while a more common class still, are produced of a cheaper material, not wrapped in a spiral form, but welded in the length by one heat by means of a pair of rollers; they are ultimately extended to their proper length by the same process. Guns are bored out in large manufactories by means of steam or other power, the instrument being a rod of steel, with its cutting portion 8 or 10 inches long, and its square sides made up with pieces of wood. Rifleing„ viz., imparting to the interior of the barrel a series of spiral curves, by means of which a perfectly direct motion is given to the bullet, involves care, attention, and skill in its preliminary stages, but is in reality a simple operation. Ordinary gun-barrels are finished by being ground on arge grindstones; those of a superior quality are turned. Breeching, or fitting in the plug at the butt which stops the end, and upon which is fitted the nozzle for the percussion cap, requires nicety and careful workmanship. Gun-barrels are coloured by means of acid; repeated coats are given until the deep rich brown is obtained; they are then polished.— W. C. A.]