A:: ERASER
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Natural rubber, also called India rubber or caoutchouc. Both words "India rubber" and "eraser" date their usage to ca. 17600–90.
A dictionary definition of eraser:
A piece of rubber or other material used to rub out marks made by ink, pencil, or chalk. The modern eraser is usually a mixture of vegetable oil, fine pumice, and sulfur bonded with rubber. The mix is processed, extruded, and vulcanized in rubber-processing equipment. In 1752 the Proceedings of the French Academy reported a suggestion for using caoutchouc, a vegetable gum produced by certain South American trees, to erase black lead marks. Caoutchouc was named rubber in 1770 by the English chemist Joseph Priestley, because it was used to rub out marks. The first patent on an integral pencil and eraser was issued in the United States to Joseph Rechendorfer of New York City on March 30, 1858. (from Dictionary.com)India-Rubber
The first notice of india-rubber on record was given nearly five hundred years ago by Herrera, who, in the second voyage of Columbus, observed that the inhabitants of Hayti played a game with balls made "of the gum of a tree," and that the balls, although large, were lighter and bounced better than the wind-balls of Castile (Herrera, Historia, dec. i. lib. iii. cap. iv.). Torquemada, however, seems to have been the first to mention by name the tree yielding it. In his De la Monarquia Indiana, published at Madrid in 1615, tom. ii., cap. x1iii. p. 663, he says, "There is a tree which the [Mexican] Indians call Ulequahuitl ; it is held in great estimation and grows in the hot country. It is not a very high tree; the leaves are round and of an ashy colour. This tree yields a white milky substance, thick and gummy, and in great abundance." He further states that the juice was collected and allowed to settle in calabashes, and was afterwards softened in hot water, or the juice smeared over the body and rubbed off when sufficiently dry, The tree mentioned by Torquernada has usually been identified as Castilloa elastica, Cerv., but the above account cannot apply to it, as that tree is described by Cervantes as one of the loftiest forest trees of the north-east coast of Mexico, and its leaves are not round but oblong-lanceolate. Torquemada mentions also that an oil was extracted from the "ulli," or rubber, by heat, possessing soft and lubricous properties, and of especial effect in removing tightness of the chest. It was also drunk with cocoa to stop haemorrhage. Even at that early date the Spaniards used the juice of the ulé tree to waterproof their cloaks. This fact, however, apparently did not attract attention in the Old World, and no rubber seems to have reached Europe until long afterwards. The first accurate information concerning any of the caoutchouc trees was furnished by La Condamine, who was sent in 1735 by the French Government to measure an arc of the meridian near Quito. (from the 1902 Encyclopedia)http://www.1902encyclopedia.com/I/IND/india-rubber.html Some history, courtesy of Wikipedia:
Before rubber erasers, tablets of rubber or wax were used to erase lead or charcoal marks from paper. Bits of rough stone such as sandstone or pumice were used to remove small errors from parchment or papyrus documents written in ink. Crustless bread was used as an eraser in the past; a Meiji-era (1868-1912) Tokyo student said: "Bread erasers were used in place of rubber erasers, and so they would give them to us with no restriction on amount. So we thought nothing of taking these and eating a firm part to at least slightly satisfy our hunger."
On April 15, 1770, Joseph Priestley described a vegetable gum to remove pencil marks: "I have seen a substance excellently adapted to the purpose of wiping from paper the mark of black lead pencil." He dubbed the substance "rubber".
In 1770, Edward Nairne, an English engineer, is credited with developing the first widely-marketed rubber eraser for an inventions competition. He sold natural rubber erasers for the high price of three shillings per half-inch cube. According to Nairne, he inadvertently picked up a piece of rubber instead of breadcrumbs, discovered rubber's erasing properties, and began selling rubber erasers. Incidentally, that was the first practical application of the substance in Europe, and rubbing out the pencil marks gave it its English name.
However, raw rubber shared the same inconveniences as bread, since it was perishable. In 1839, inventor Charles Goodyear discovered the process of vulcanization, a method that would cure rubber and make it a durable material. Rubber erasers became common with this advent of vulcanization.
On March 30, 1858, Hymen Lipman of Philadelphia, USA, received the first patent for attaching an eraser to the end of a pencil. It was later invalidated because it was determined to be simply a composite of two devices rather than an entirely new product.
Erasers may be rectangular blocks (block and wedge eraser), or conical caps that can slip onto the end of a pencil (cap eraser). A barrel or click eraser is a device shaped like a pencil, but instead of being filled with pencil lead, its barrel contains a retractable cylinder of eraser material (most commonly soft vinyl). Novelty erasers, in a dual role as figurines (such as musical notes, animals, confectionery), are mostly decorative, as their hard vinyl tends to smear heavy markings. (from Wikipedia.com)
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