WIRE 



G319 



WIRE GLASS 



W8 10,132; in 1916 it was 12,692 (Federal esti- 

 mate). 



WIRE, a long, thin rod of metal, usually 

 round, having a great variety of industrial uses: 

 Telephone and telegraph wires, trolley wires, 

 nails, fences, various kinds of screening devices 

 and strings for musical and scientific instru- 

 ments are some of the important articles manu- 

 factured from wire. Only such metals as are 

 ductile, that is, have the property of being 

 drawn out, are suitable for making wire; the 

 principal ones are silver, copper, iron, platinum, 

 gold and aluminum, with their alloys. Plati- 

 num is employed for the wires of extreme fine- 

 ness used in telescopes; such wires have been 

 drawn to a diameter of one-fifty-thousandth of 

 an inch. 



Process of Manufacture. Wire was once pro- 

 duced by hammering metal laboriously into 

 plates, which were then cut into strips and 

 rounded by beating. Machines have now en- 

 tirely superseded hand labor. Steel or iron 

 billets are put through a rolling process, from 

 which they emerge as long rods about a quarter 

 of an inch in diameter. These rods are wound 

 on reels while still hot, and are cleansed, first in 

 a bath of sulphuric acid and later in water. 



The making of wire consists essentially in 

 drawing such rods to a still smaller diameter, 

 and this is accomplished by putting them 

 through a series of steel dies. The die has the 

 shape of a funnel with a round vent smaller 

 than the rod. The rod is sharpened at one end 

 by hammering, so that it may be run into the 

 die much as a strand or two of thread is run 

 into the eye of a needle. As soon as it is 

 passed through the die, the sharpened end is 

 seized with a pair of pincers and drawn far 

 enough to be attached to an upright drum, 

 which rotates on a vertical shaft. This drum 

 is then set in motion, and the wire is pulled 

 through the die and wound on the drum. Tin- 

 process of drawing has a tendency to harden 

 . so that it has to be softened and rendered 

 less brittle by being placed in cast-iron pots 

 and subjected to heat. This process is call.. I 

 annealing. Each time wire is so annealed it 

 has a tendency to scale and raus't be subjected 

 to an acid bath for cleaning. Win- \\lr.rh is to 

 be used in m : - is not softened m 



way, as it would not have sufficient hardness. 



Steel cables having a tensile strength of 130 

 tons to the square inch have been produced of 

 years. Such wire is hardened and tem- 

 pered before being drawn. Commercially, wire 

 is distinguished by its gauge; it varies from 



No. 0000, which is .46 inches, to No. 36, which 

 is .005 inches. The shape may be square, oval, 

 flat, triangular, etc., but is usually round. For 

 drawing the finest kinds of wire, extremely 

 hard dies of diamonds and rubies are used. 



Much of the wire used for fencing is barbed. 

 Such wire consists of two or more wires, twisted 

 together and having short, t hornlike projections 

 at frequent intervals, or of a single wire fur- 

 nished with sharp points. It makes a very 

 effective barrier. Barbed wire is another 

 American invention which was employed ef- 

 fectively by all armies in the War of the Na- 

 tions in Europe. It was stretched between op- 

 posing trench systems in a veritable network, 

 to hinder or prevent an enemy attack. Some- 

 times it was heavily charged with electricity. 

 In 1916 it was declared that 200,000 miles of 

 barbed wire had been used within one year for 

 this purpose. All wires used for fencing, to- 

 gether with telephone, telegraph and trolley 

 wires, are galvanized to prevent rusting when 

 exposed to the weather (see GALVANIZED IRON). 



Consult Smith's Wire: Its Manufacture and 

 Uses. 



WIRE GLASS, a combination of wire and 

 glass largely used in window construction in 

 those parts of modern buildings most exposed 

 to danger of fire and robbery. The invention 

 of wire glass is attributed to two men, Frank 

 Shuman of Philadelphia and Leon Appert of 

 France; they achieved practically the same re- 

 sult by different processes. The Appert process 

 consists of rolling one sheet of glass, laying tin 

 meshed wire on it and then rolling another 

 sheet of glass on the top, pressing the wire and 

 the sheets of glass into one solid sheet. 

 Shuman process consists of rolling one sheet 

 of glass, into which the wire netting is pressed 

 and rolled. The strength of the glass is. greatly 

 increased by the introduction of the \\in-. tin 

 ingress of light is not affected, and on account 

 of its greater strength wire glass may be safely 

 used where ordinary glass would be broken. 



As a fire retardant, wire glass has particular 

 value, for if broken or cracked it seldom fall-. 

 but holds its place, preventing the entrant 

 air which might fan the flames. Wire glass 

 may be finished smooth and p< 

 semble plate glass, or it may be ribbed, "rough 

 rolled," or pancd, according to taste. The use 

 of wire glass is st< reasing in all fin - 



proof buildings and effects a great saving in 

 lit of material. It does not present as good 

 an appearance as ordinary glass, so its use is 

 limited to side and rear windows. 



