Needle

Needle (0. Eng. ncedl; the word appears in various forms in Teutonic languages, Ger. Nadel, Dutch naal, the root being ne-, to sew, cf. Ger. ndhen, and probably Lat. nere, to spin, Gr. vi ocs, spinning), an instrument adapted for passing a thread through fabrics in sewing, consisting of a thin rod of steel, having a pointed end and pierced with a hole or "eye" to carry the thread. The term is also applied to various other objects that more or less resemble a sewing needle in form, though differing in function, such as the magnetized piece of steel that points north and south in the mariner's compass, the pointer or indicator of certain forms of electric telegraph instruments, the slender tube by which the contents of a hypodermic syringe are injected beneath the skin, a sharp-pointed mountain peak or isolated mass of rock, &c.

  


Sewing needles have been in use from prehistoric times. Originally they were made of fishbone, bone or ivory, and their first form was probably a rude bodkin having a hook instead of an eye, though bone needles with an eye, sometimes at the end and sometimes in the middle, have been found in cave deposits in Great Britain and France and in the Swiss lakes. Bone needles continue to be used by uncivilized tribes, but since the discovery of bronze metal needles have been employed in civilized communities. Steel needles were introduced into Europe by the Moors, and it is on record that they were being made at Nuremberg in 1370. In England their manufacture was established about 1650. The centre of the trade in England is Redditch, in Worcestershire, with several other small towns in Warwickshire. Originally the industry was domestic in its character, but it is now carried on in factories where mechanical appliances have to a great extent supplanted handwork. Large quantities of needles are also manufactured on the continent of Europe, Aix-la-Chapelle being an important centre of their production. In the United States ordinary sewing needles are not made, though there is a large output of the special forms used in sewing machines.

The raw material of needle-manufacture consists of Sheffield crucible steel drawn down into wire of suitable gauge. The wire is supplied in coils of definite weight and diameter, and the first operation is to cut the coils into lengths, each sufficient for two needles. These lengths are next straightened. For this purpose a bundle containing several thousand lengths is packed within two strong iron rings, is heated to red heat, and is then pressed on an iron plate having two parallel grooves in which the iron rings run. Over this plate the bundle is worked backward and forward by the pressure of an oblong slightly curved iron tool having two longitudinal slits through which the edges of the rings project. Thus, by combined pressure and rolling the whole of the lengths quickly become perfectly straight and even. The next operation consists in pointing both ends of the wires. This was formerly done by hand by a grinder who, holding several dozen wires against a grindstone with his left hand and slightly revolving them with his right, was able to point about Ioo,000 needles a day, the number depending, however, to some extent on the size treated. This method, however, is now largely superseded by machinery, which is still more expeditious. The wires are fed out from a hopper to a revolving wheel, on the periphery of which they are held by an india-rubber band. This wheel revolves at right angles to a revolving hollow grindstone, and so each wire is brought up to the stone in rapid succession and pointed at one end, the process being repeated for the other end. The next operations are to stamp the grooves which are to be found at the head of a needle and to punch the oval eyes, both being done by automatic machinery. Each wire now forms two needles attached head to head by a broad thin scarf of steel. The operation of separating them is largely performed by machines which pass the double blanks over the face of an emery wheel, but an older method is to spit them on two flattened wires, clamp them tightly in a frame, file away the scarf and break the blanks in halves, so that two lots of single needles are obtained, each spitted on a wire. The next step, after the heads have been filed smooth, is to harden and temper the needles, which are heated to redness, plunged into cold oil, and then gently heated by being placed on a continuous band passing over a series of gas flames. After the tempering comes the process of scouring, and then the eyes are smoothed and polished so that they will not cut the thread. For this purpose the heads used to be softened by blueing, and the needles strung loosely on wires covered with a paste of emery and oil. These wires were then suspended between uprights on a frame platform to which a jerking motion was communicated; in this way the needles were made to swing on the wires and the gentle friction effected the desired end. Generally, however, the eyes are cleared by the action of a concave wire brush, before the scouring process, and then subsequent burnishing becomes unnecessary. The bodies are next polished by being passed between revolving leather rollers which have also a lateral motion in the direction of their axes. The heads of the finished needles have now to be brought all in one direction. Formerly this was done by a "header," wearing a cloth cap on one of her fingers; this being pressed against a batch of the needles which had previously been arranged parallel to each other, those whose heads were presented to the cloth stuck in it and thus were withdrawn. A more modern device is to roll them down a smooth inclined plane, when the pointed ends, owing to their conical form, travel more slowly than the thicker ends, and thus the needles are all brought round so that they point the same way. They are then sorted according to their lengths, and are done up into packets for the market.

Besides ordinary needles for hand sewing, many varieties are made for use in sewing machines, and in their production automatic machinery is largely utilized. Those used for sewing leather have points of various special forms (twist, chisel, wedge, diamond, &c.) instead of the round point of the ordinary needle, and sometimes have a hook in place of an eye. Knitting needles are long slender rods, usually of steel but sometimes of bone or other material, having neither hooks nor eyes. Crochet needles are provided with a hook. Hooked needles again are employed in knitting and stockinet machines; having to be periodically closed by the operation of the mechanism the hooks in one type are made flexible so that they can be pushed down on the shank, while in another the same end is served by providing them with a minute latch. Another special class is constituted by the numerous varieties of needles used by surgeons for suturing wounds, &c. (see Surgical Instruments).