WIRE DRAWING. Wire is a metal elongated into the form of a slender rod, generally' cylindrical, but not necessarily so. In early times, metals were probably beaten out with a hammer into thin plates or leaves, which were then divided into small slips by means of scissors or some other cutting in strument, these slips being subsequently rounded by a hammer and file, so as to form threads or wires. So long as wire was formed by the hammer, the artists of NUrnberg, by whom it was fabricated, were styled wire smiths,' but subsequent to the introduction of the drawing process their designation was changed to ' wire drawers.' Beckmann con ceives that the invention of wire drawing must be assigned to the 14th century. Pre vious to 1565 all English iron wire appears to have been drawn by manual strength. The first wire-mill in England was set up at Sheen, near Richmond, by a Dutchman, in 1662.
For the manufacture of iron wise the very best and toughest iron is selected. Before the process of rolling with grooved rollers had be come common, the iron was prepared for use by a slow and tedious process. At the pre sent day the preparing of iron for the wire drawers is performed by means of rollers, which are generally 7 or 8 inches in diameter, and are sometimes made to perform 350 re volutions in a minute. A bar of steel 30 inches long and an inch square, heated to redness, is passed between the .rollers, through grooves successively diminishing in size, eight times in less than a minute, and is thereby elongated to from 20 to 30 feet. For ordinary wire the rods are commonly reduced to a thickness of about one-eighth of an inch by this process ; and these rods themselves arc used as wire for some purposes. The kind of cast-steel wire of which the best needles and some other articles are made, is not usually submitted to the rolling process, but, after being tilted to about a quarter of an inch square, it is rounded on an anvil previous to elongation by the draw-plate.
The drawing of wire is thus managed. The draw-plate is usually formed of a stout piece of shear-steel, about six inches long and an inch and a half in diameter, but being somewhat reduced in thickness towards each end, like a cucumber, and flattened on one side. It is
pierced transverely with several conical holes, the larger orifices of which open upon the flattened surface of the plate, while their smaller orifices are carefully finished to the size to which it is intended to reduce the wire drawn through them. In drawing wire by hand the draw-plate is laid against two upright pillars fixed on a bench or table, and, the extreme end of the wire to be drawn being so reduced as to enable it readily to pass through the hole, a small portion is drawn through by a lever apparatus, and attached to a cylindrical drum, mounted on a vertical axis. The work man then takes in one band the coil of thick wire to be reduced, and in the other a lever handle attached to the drum ; and while he turns the drum so as to wind the wire upon its circumference, and consequently to draw it through the plate, he imparts a kind of twist to the wire which enters the plate, by a pecu liar motion of the hand in which the coil is supported.
The size of wire is commonly measured by means of a gauge, which consists of a plate of steel with a series of deep notches or slits at each edge, varying slightly from each other in width, and numbered according to the number given to wire of corresponding size.
The use of wire in manufactures has largely extended within the last few years, principally owing to the success with' which a weaving process has been applied to it. The following are only some among' the many applications of wire now genefally adopted :—Wire netting for enclosing young plantations ; strong wire netting for sheep folds, or for enclosures gene rally in farms ; ornamental wire fences for pleasure grounds pheasantries- and hen coops; garden bordering; plant guards; hur dles for horse and cattle pastures ; fences and gates ; plant trainers ; arbours and arches ; plant umbrellas and canopies ; flower stands and stages; garden chairs ; bedsteads ; wire gauze blinds ; sieves and riddles ; Venetian blinds ; bird cages ; fire guards ; safety lamps and lanterns ; meat covers and safes. Lastly, we may mention wire ropes, of the use of which a few illustrations have been given under ROPE MAKING and SUSPENSION BRIDGE S.