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Pin

PIN (a doublet with " pen " from Lat. pinna, feather, pinnacle, which is said to contain the same root as TUTUJ, pine tree, and properly to mean a sharp point or end), a small peg or bolt of metal or wood, not necessarily pointed, employed as a fastening to connect together different parts of an article, as a stop to limit the motion of some moving piece in a machine, as a support on which a small wheel may turn, etc., but most commonly a small metal spike, used for fastening portions of fabrics together, having one end pointed and at the other a bulbed head, or some other arrangement for preventing the spike from passing entirely through the cloth or other material with which it is employed. In one form or another pins of this last kind are of the highest antiquity, the earliest form doubtless being a natural thorn. Pins of bronze, and bronze brooches in which the pin is'the essential feature, are of common occurrence among the remains of the bronze age. The ordinary domestic pin had become in the 15th century an article of sufficient importance in England to warrant legislative notice, as in 1483 the importation of pins was prohibited by statute. In 1540 Queen Catherine received pins from France, and again in 1543 an act was passed providing that " no person shall put to sale any pinnes but only such as shall be double headed, and have the heads soldered fast to the shank of the pinnes, well smoothed, the shank well shapen, the points well and round filed, canted and sharpened." At that time pins of good quality were made of brass; but a large proportion of those against which the legislative enactment was directed were made of iron wire blanched and passed as brass pins. To a large extent the supply of pins in England was received from France till about 1626, in which year the manufacture was introduced into Gloucestershire by John Tilsby. His business flourished so well that he soon gave employment to 1500 persons, and Stroud pins attained a high reputation. In 1636 the pinmakers of London formed a corporation, and the manufacture was subsequently established at Bristol and Birmingham, the latter town ultimately becoming the principal centre of the industry. So early as 1775 the attention of the enterprising colonists in Carolina was drawn to the manufacture by the offer of prizes for the first native-made pins and needles. At a later date several pin-making machines were invented in the United States. During the war of 1812, when the price of pins rose enormously, the manufacture was actually started, but the industry was not fairly successful till about the year 1836 when the Howe Manufacturing Company was formed at Birmingham, Connecticut. Previous to this an American, Lemuel W. Wright, had in 1824 secured in England a patent for a machine to make solid-headed pins, which established the industry on its present basis.

The old form of pin consisted of a shank with a separate head of fine wire twisted round and secured to it. Fine wire for heads was first wound on a lathe round a spit the exact circumference of the pin shanks to be headed. In this way a long elastic spiral was produced which had next to be cut into heads, each consisting of two complete turns of the spiral. These heads were softened by annealing and made into a heap for the heading boy, whose duty was to thrust a number of shanks into the heap and let as many as might be fit themselves with heads. Such shanks as came out thus headed were passed to the header, who with a falling block and die arrangement compressed together shank and head of such a number as his die-block was fitted for. All the other operations of straightening the wire, cutting, pointing, etc., were separately performed, and these numerous details connected with the production of a common pin were seized on by Adam Smith as one of the most remarkable illustrations of the advantages of the division of labour.

The beautiful automatic machinery by which pins are now made of single pieces of wire is an invention of the 19th century. In 1817 a communication was made at the Patent Office by Seth Hunt, describing a machine for making pins with " head, shaft and point in one entire piece." By this machine a suitable length of wire was cut off and held in a die till a globular head was formed on one end by compression, and the other end was pointed by the revolution around it of a roughened steel wheel. This machine does not appear to have come into use; but in 1824 Wright patented the pin-making apparatus above referred to as the parent form of the machinery now employed. A factory equipped with his machines was established in London, but the company which owned it was not successful. The plant passed into the hands of Daniel FooteTayler of Birmingham, who obtained an extension of Wright's patent for five years from 1838, and his firm was the first to carry on the production of machine-made solid-headed pins on a commercial basis. In a modern pin- making machine wire of suitable gauge running off a reel is drawn in and straightened by passing between straightening pins or studs set in a table. When a pin length has entered it is caught by lateral jaws, beyond which enough of the end projects to form a pin-head. Against this end a steel punch advances and compresses the metal by a die arrangement into the form of a head. The pin length is immediately cut off and the headed piece drops into a slit' sufficiently wide to pass the wire through but retain the head. The pins are consequently suspended by the head while their projecting extremities are held against a revolving cutter, by which they are pointed. They are next cleaned by being boiled in weak beer, and then arranged in a copper pan in layers alternating with layers of grained tin. The contents of the pan are covered with water over which a quantity of argol (bitartrate of potash) is sprinkled, and after boiling for several hours the brass pins are coated with a thin deposit of tin, which gives them their silvery appearance. They are then washed in clean water, and dried and polished by being revolved in a barrel, mixed with dry bran or fine sawdust, from which they are winnowed finished pins. A large proportion of the pins sold are stuck into paper by an automatic machine not less ingenious than the pinmaking machine itself. Mourning pins are made of iron wire, finished by immersing in black Japan and drying in a stove. A considerable variety of pins, including the ingeniously coiled, bent and twisted nursery safety pin, ladies' hairpins, etc., are also made by automatic machinery. The sizes of ordinary pins range from the 3J-in. stout blanket pin down to the finest slender gilt pin used by entomologists, 4500 of which weigh about an ounce.

Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)

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