wire, metal filament, strand, or solid rod usually having a round cross section. Metals and alloys used for wiremaking are chosen for high tensile strength and ductility or for their electrical conductivity, weight, melting point, or other properties, depending upon the use to which the wire is to be put. The size of a wire is the measure of its diameter. For convenience, the different wires are numbered in order of decreasing size, the number being known as the gauge, or gage; the higher the gauge the smaller the diameter. The number of gauges used and their sizes differ according to the kind of wire and the country's standards of measurement. In the United States the American wire gauge, known also as the Brown & Sharpe wire gauge (abbr. B. & S.), is used; in Great Britain and Canada the British, or imperial, standard wire gauge (S.W.G.) is employed. For steel wire the steel wire gauge (also known as the Washburn & Moen, the Roebling, or the American Steel & Wire Co.'s wire gauge) is employed. Wire is widely used in conducting electricity and in making fencing, screens, netting, springs, and mesh or cloth. Very thin wire is used in various scientific instruments. A wire mesh is often used in glass (wire glass) to prevent shattering and to increase strength and safety. Wire rope (cable) is made by forming wires into strands that are then wound on a core. Wire has been used since the 3d millennium B.C. In early times the metal was hammered into sheets, then cut in strips and shaped with hammer and file. The modern method of drawing wire is believed to have originated in Europe late in the 13th cent. In this process the metal is pulled, or drawn, through a number of holes, each smaller than the one preceding, until finally it is passed through the hole having the desired diameter. Metal plates with such holes are known as drawplates or dies. Success in drawing wire through the drawplate formerly depended upon the physical strength of the wiredrawer (or wiresmith), since machinery was not used until the introduction of power-driven cylinder blocks to pull and coil the wire. With the establishment of telegraph lines in the late 1800s, the production of wire expanded into one of the greatest industries of the 19th cent.