Page:EB1911 - Volume 28.djvu/758

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738
WIRE

Gregory XIII. abbot of the Benedictine monastery of St James, Regensburg. There he died on the 21st of September 1592.

Winzet's works are almost entirely controversial. He justified his literary activity on the side of Catholicism on the double plea of conscience and the inability of the bishops and theologians to supply the necessary arguments (First Tractate, ed. S.T.S., i. p. 10). “We may nawayis langer contene vs,” he writes, “bot expresse on al sydis as we think, referring our iugement to the haly Catholik Kirk.” In his first work, Certaine Tractates (three in number), printed in 1562, he rates his fellow clergy for negligence and sin, invites replies from Knox regarding his authority as minister and his share in the new ecclesiastical constitution, and protests against the interference with Catholic burgesses by the magistrates of Edinburgh. The Last Blast, which was interrupted in publication, is an onslaught on heretics and a falsely ordained clergy. In his Buke of Four Scoir Thre Questions (1563), addressed to the “Calviniane Precheouris,” in which he treats of church doctrine, sacraments, priesthood, obedience to rulers, free-will and other matters, he is dogmatic rather than polemical. He translated the Commonitorium of Vincentius Lirinensis (1563), and wrote, in Latin, a Flagellum sectarionum and a Velitatio in Georgium Buchananum (1582).

Winzet's vernacular writings have been edited by J. Hewison for the S.T.S. (2 vols., 1888, 1890). The Tractates were printed, with a preface by David Laing, by the Maitland Club (1835). For Winzet's career see Zeigelbauer, Historia rei literariae O.S.B. iii., Mackenzie, Lives, iii., and the Introduction to S.T.S., edit. u.s.

WIRE (A.S. wir, a wire; cf. Swed. vire, to twist, M.H.G. wiere, a gold ornament, Lat. viriae, armlets, ultimately from the root wi, to twist, bind), a thin long rod of metal, generally round in section. The uses of wire are multifarious and diverse beyond all enumeration. It forms the raw material of important manufactures, such as the wire-net industry, wire-cloth making and wire-rope spinning, in which it occupies a place analogous to a textile fibre. Wire-cloth of all degrees of strength and fineness of mesh is used for sifting and screening machinery, for draining paper pulp, for window screens, and for many other purposes. Vast quantities of copper and iron wire are employed for telegraph and telephone wires and cables, and as conductors in electric lighting. It is in no less demand for fencing, and much is consumed in the construction of suspension bridges, and cages, &c. In the manufacture of stringed musical instruments and philosophical apparatus wire is again largely used. Among its other sources of consumption it is sufficient to mention pin and hair-pin making, the needle and fish-hook industries, nail, peg and rivet making, and carding machinery; indeed there are few industries into which it does not more or less enter.

The physical properties requisite to make useful wire are possessed by only a limited number of metals and metallic alloys. The metals must in the first place be ductile; and, further, the wire when drawn out must possess a certain amount of tenacity, the quality on which the utility of wire principally depends. The metals suitable for wire, possessing almost equal ductility, are platinum, silver, iron, copper, aluminium and gold; and it is only from these and certain of their alloys with other metals, principally brass and bronze, that wire is prepared. By careful treatment wire of excessive tenuity can be produced. Dr W. H. Wollaston first succeeded in drawing a platinum wire 1/30000 inch in diameter by encasing a fine platinum wire within silver to ten times its diameter. The cored wire he then reduced to 1/3000 inch, and by dissolving away the silver coating the platinum wire 1/30000 inch thick only remained. By continued treatment in this way wires of platinum for spider-lines of telescopes have been obtained of such extreme tenuity that a mile length of the wire weighs not more than a grain; and it is said that platinum wire has been made which measures not more than 1/2000 mm., equal to less than the fifty-thousandth part of an inch, accompanying table shows the comparative tenacity of the of metals and metallic alloys.

 Diameter.  Strain.

 
Gold
Platinum
Silver
Copper
Iron
Copper
Brass
Steel
Phosphor Bronze 

In.
.0162
.0161
.0157
.0177
.0169
.0605
.0640
.0600
.0630

℔.
5.61 - 5.42
6.70 - 6.59
7.86 - 7.78
 10.11 - 10.20 
11.12 - 10.89
233
203
342
394

Wire was originally made by beating the metal out into plates, which were then cut into continuous strips, and afterwards rounded by beating. The art of wire-drawing does not appear to have been known till the 14th century, and it was not introduced into England before the second half of the 17th century. Wire is usually drawn of cylindrical form; but it may be made of any desired section by varying the outline of the holes in the draw-plate through which it is passed in the process of manufacture. The draw-plate or die is a piece of hard cast-iron or hard steel, or for fine work it may be a diamond or ruby. The object of utilizing precious stones is to enable the dies to be used for a considerable period without losing their size, and so producing wire of incorrect diameter. Diamond dies must be rebored when they have lost their original diameter of hole, but the metal dies are brought down to size again by hammering-up the hole and then drifting it out to correct diameter with a punch. The form of a die in section is shown by fig. I; the bell-mouthed opening receives the wire, and when it is pulled through the hole at the end its diameter becomes reduced accordingly. The action of drawing has the effect of hardening the wire and rendering it brittle, so that annealing must be done at intervals to soften it again for further drawing; the annealing is done in cast-iron pots, holding coils of wire which are raised to a red heat and then allowed to cool. Although the wire is kept air-tight as much as possible, some amount of scaling occurs, and pickling must be done to remove this scale before redrawing.

Fig. 1.

An important point in wire-drawing is that of lubrication to facilitate the operation and to lessen the wear on the dies. Various lubricants, such as oil, tallow, soapy water and stale beer, are employed. Another method is to immerse the wire in a sulphate of copper solution, so that a film of copper is deposited which forms a kind of lubricant, easing the drawing considerably; in some classes of wire the copper is left after the final drawing to serve as a preventative of rust.

The wire-drawing machines include means for holding the dies accurately in position and for drawing the wire steadily through the holes. The usual design consists of a cast-iron bench or table having a bracket standing up to hold the die, and a vertical drum which rotates and by coiling the wire around its surface pulls it through the die, the coil of wire being stored upon another drum or “swift” which lies behind the die and reels off the wire as fast as required. The wire drum or “block” is provided with means for rapidly coupling or uncoupling it to its vertical shaft, so that the motion of the wire may be stopped or started instantly. The block is also tapered, so that the coil of wire may be easily slipped off upwards when finished. Before the wire can be attached to the block, a sufficient length of it must be pulled through the die; this is effected by a pair of gripping pincers on the end of a chain which is wound around a revolving drum, so drawing the pincers along, and with them the wire, until enough is through the die to be coiled two or three times on the block, where the end is secured by a small screw clamp or vice ready for the drawing operation. Wire has to be pointed or made smaller in diameter at the end before it can be passed through the die; the pointing is done by hammering, filing rolling or swaging in dies, which effect a reduction in diameter. When the wire is on the block the latter is set in motion and the wire is drawn steadily through the die; it is very important that the block shall rotate evenly and that it shall run true and pull the wire in an even manner, otherwise the “snatching” which occurs will break the wire, or at least weaken it in spots.

Continuous wire-drawing machines differ from the single-block machines in having a series of dies through which the wire passes in a continuous manner. The difficulty of feeding between each die is solved by introducing a block between each, so that as the wire issues it coils around the block and is so helped on to the next die. The speeds of the blocks are increased successively, so that the elongation due to drawing is taken up and slip compensated for. The operation of threading the wire first through all the dies and around the blocks is termed “stringing-up.” The arrangements for lubrication include a pump which floods the dies, and in many cases also the bottom portions of the blocks run in lubricant. The speeds at which the wire travels vary greatly, according to the material and the amount of reduction effected; rates from 100 ft. up to 900 ft. are possible, the higher speeds being those of continuous machines.

Wires and cables for electrical purposes are covered with various insulating materials, such as cotton, silk, jute and paper, wrapped in spiral fashion and further protected with substances such as paraffin, some kind of preservative compound, bitumen or lead sheathing or