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cotton gin

 
Dictionary: cotton gin

n.
A machine that separates the seeds, seed hulls, and other small objects from the fibers of cotton.


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Machine for cleaning cotton of its seeds. The design that became standard was invented in the U.S. by Eli Whitney in 1793. The mechanization of spinning in England had created a greatly expanded market for U.S. cotton, but production was bottlenecked by the manual removal of the seeds from the raw fibre. The cotton gin pulled the cotton through a set of wire teeth mounted on a revolving cylinder, the fibre passing through narrow slots in an iron breastwork too small to permit passage of the seed. The simplicity of the invention caused it to be widely copied. It is credited with making cotton the most important export crop of the U.S. before the American Civil War, as settlers and their slaves spread westward through prime cotton-growing regions of South Carolina, Georgia, Alabama, Mississippi, and Texas.

For more information on cotton gin, visit Britannica.com.

US History Encyclopedia: Cotton Gin
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Cotton Gin, the implement or machine used to pull the cotton fibers from the seed. Each fiber grows from the seed like hairs from the head. There are two basic types—the black-seed cotton, from which the fibers pull away rather easily, and the green-seed cotton, from which it is difficult to free the fibers. North American colonists commonly used the roller gin, adapted from the "churka" of India, with which cotton fibers were pulled from the seed by hand-turned rollers. These implements could be used only to gin the Sea Island cotton, a black-seed type; the rollers crushed the green seeds and stained the fiber. But in the ever increasing inland acreage, only green-seed cotton could be grown, and this had to be ginned by hand.

In 1792 Eli Whitney, a Yale graduate then tutoring at an estate near Savannah, Georgia, found that many planters were interested in increasing their cotton production but were frustrated By the inefficiency of having to manually remove the seeds before the fiber could be baled for shipment. In a letter to his father (11 September 1793), Whitney wrote that if a machine "could be invented which would clean the Cotton with expedition, it would be a great thing both to the Country and to the inventor." In the same letter he boasted that his invention would "do more than fifty men with the old machines." Although the reference to "old machines" has been interpreted by some authors to mean the roller gins, it may not; there are unproven claims that Whitney had seen machines similar to his prior to his invention. Nevertheless, Eli Whitney was granted a patent on 14 March 1794 for a "new and useful improvement in the mode of Ginning Cotton." His machine used spiked teeth set into a wooden cylinder to pull the cotton fibers through the slots in a metal breastplate; the slots were too small to allow the seeds to pass through. A second cylinder with brushes freed the fibers from the teeth. Court cases involving competing patents for gins with sawtoothed cylinders were found in Whitney's favor; the saw pattern would eventually be preferred as the more efficient system of gin design.

Whitney and his partner, Phineas Miller, kept the cotton gin under their immediate control by selling ginning services, not machines. When a fire in their New Haven manufacturing shop delayed a shipment of gins, southern blacksmiths began making their own versions of the easily copied machine. After years of court suits, several southern states finally paid Whitney. He received almost $100,000 for the patent rights—a relatively modest amount for a patent that would increase cotton production in America from 3,000 bales in 1790 to more than 2 million bales By 1850. By 1836 cotton comprised two-thirds of all American exports. Patented improvements in the mechanization of the earlier roller gin began in the 1830s, and improvements in the saw gin continued throughout the nineteenth century, although the basic principle remained the same.

Bibliography

Britton, Karen G. Bale O'Cotton: The Mechanical Art of Cotton Ginning. College Station: Texas A&M University Press, 1992.

Nevins, Allan, and Jeannette Mirskey. The World of Eli Whitney. New York: MacMillan, 1952.

—Grace R. Cooper/A. R.

 
Columbia Encyclopedia: cotton gin
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cotton gin, machine for separating cotton fibers from the seeds. The charkha, used in India from antiquity, consists of two revolving wooden rollers through which the fibers are drawn, leaving the seeds. A similar gin was early used in the S United States for long-staple cotton. In the modern roller gin, rollers covered with rough leather draw out the fibers, which are cut off by a fixed knife pressed against the rollers. This type of gin cleans only about two bales per day, but it does not snarl or break the fibers. The saw gin, invented by the American inventor Eli Whitney in 1793 and patented in 1794, consisted of a toothed cylinder revolving against a grate that enclosed the seed cotton. The teeth caught the fibers, pulling them from the seeds; the fibers were then removed from the cylinder by a revolving brush. This device, especially suited to short- and medium-staple cotton, has been mechanized and is used in commercial plants that are also called gins, where the fiber is conveyed from farm wagon to baler by air suction. Such plants have one or more gin stands, each with a series of from 70 to 80 circular saws set on a shaft. The fibers, freed from dirt and hulls, are pulled through a grid by the saw teeth to remove the seeds. The fibers are removed from the saw teeth by a revolving brush or by a blast of air (in more modern plants) and are then carried by air blast or suction to a condenser and finally to the baling apparatus.


Wikipedia: Cotton gin
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Cotton gin patent, March 14, 1794
A cotton gin on display at the Eli Whitney Museum.
An engraving from Harper's Magazine from 1869 depicting the first cotton gin more than 70 years earlier

A cotton gin (short for cotton engine[1]) is a machine that quickly and easily separates the cotton fibers from the seeds, a job previously done by hand. These seeds are either used again to grow more cotton or, if badly damaged, are disposed of. It uses a combination of a wire screen and small wire hooks to pull the cotton through the screen, while brushes continuously remove the loose cotton lint to prevent jams.

Contents

Origins

The earliest versions consisted of a single roller made of iron or wood and a flat piece of stone or wood. Evidence for this type of gin has been found in Africa, Asia, and North America. The first documentation of the cotton gin by contemporary scholars is found in the fifth century AD. Visual evidence of the single-roller gin exists in the form of fifth-century Buddhist paintings in the Ajanta Caves in western India. These early gins were difficult to use and required a great deal of skill. A narrow single roller was necessary to expel the seeds from the cotton without crushing the seeds. The design was similar to that of a metate, which was used to grind grain. The earliest history of the cotton gin is ambiguous due to the fact that archeologists likely mistook the cotton gin's parts for other tools.[2]

Between the twelfth and fourteenth centuries, dual roller gins appeared in India and China. The Indian version of the two roller gin was prevalent throughout the Mediterranean cotton trade by the sixteenth century. This mechanical device was, in some areas, driven by water power.[3]

The modern version of the cotton gin was created by the American inventor Eli Whitney in 1793 to mechanize the cleaning of cotton. The invention was granted a patent on March 14, 1794. There is slight controversy over whether the idea of the cotton gin and its constituent elements are correctly attributed to Eli Whitney. The popular version of Whitney inventing the cotton gin is attributed to an article on the subject in the early 1870s and later reprinted in 1910 in the The Library of Southern Literature. In this article the author mentioned how Catherine Littlefield Greene suggested to Whitney the use of a brush-like component instrumental to separate out the seeds and cotton. Because social norms inhibited women from registering for patents, Eli Whitney received the patent-and the sole credit in history textbooks until recently.

Many people attempted to develop a design that would process short staple cotton and Hodgen Holmes, Robert Watkins, William Longstreet, and John Murray were all issued patents for improvement to the cotton gin by 1796.[4] However, the evidence indicates that Whitney did invent the saw gin, for which he is famous. Although he spent many years in court attempting to enforce his patent against planters who made unauthorized copies, a change in patent law ultimately made his claim legally enforceable—too late for him to make much money off of the device in the single year remaining before patent expiration.[5].

The engraving from Harper's Magazine shows a roller gin, which was not invented by Eli Whitney.

Effects of the cotton gin

The immediate effect of the gin was to cause a massive growth in the production of cotton in the American South. Whereas cotton had formerly required considerable labor to clean and separate the fiber from the seeds, the cotton gin revolutionized the process. The wholesale price of cotton plummeted as output increased dramatically. Cotton cloth (which had formerly been quite expensive) was manufactured in bulk in England and the Northeastern United States. Large areas of land in American states such as Mississippi were cleared and planted with cotton to meet increasing demand. A by-product of the cotton gin was the expansion of slavery through the region, as laborers were needed to plant and harvest cotton.[according to whom?] Many of the plantations of the Antebellum South were built on fortunes gained from the use of the cotton gin. One of the inevitable results of the expansion of cotton cultivation was that it caused more slaves to be imported into the newer cotton producing states from the older slave states.[according to whom?] Also, the growth of the cotton industry deterred the growth of manufacturing in the south, as money and capital was diverted from industrial production to pay for the additional slaves and land required for the expansion of cotton production.[according to whom?]

According to the Eli Whitney Museum site, "Whitney (who died in 1825) could not have foreseen the ways in which his invention would change society for the worse. The most significant of these was the growth of slavery. While it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton. In fact, the opposite occurred. Cotton growing became so profitable for the planters that it greatly increased their demand for both land and slave labor. In 1790 there were six slave states; in 1860 there were 15. From 1790 until Congress banned the importation of slaves from Africa in 1808, Southerners imported 80,000 Africans. By 1860 approximately one in three Southerners was a slave.[6].

How Whitney's model works

Whitney's cotton gin model cleans 50 pounds of lint per day[7]. The model consists of a wooden cylinder surrounded by rows of slender spikes which pull the lint through the bars of a comb-like grid [7]. The grids are closely spaced, prohibiting the seeds from passing through.

Diagram of a modern gin plant - courtesy USDA

Notes

  1. ^ Merriam-Webster Dictionary
  2. ^ Lakwete, 1-6.
  3. ^ Baber, page 57
  4. ^ Lakwete, 64-76.
  5. ^ The American Historical Review by Henry Eldridge Bourne, Robert Livingston Schuyler Editors: 1895–July 1928; J.F. Jameson and others.; Oct. 1928–Apr. 1936, H.E. Bourne and others; July 1936–Apr. 1941, R.L. Schuyler and others; July 1941– G.S. Ford and others. Published 1991, American Historical Association [etc.], pp 90–101.
  6. ^ http://www.eliwhitney.org/museum/eli-whitney/cotton-gin Creative Commons Attribution-Noncommercial-Share Alike License
  7. ^ a b M E Harr. (1977). "Mechanics of particulate media; A probabilistic approach". McGraw-Hill.

References

  • Baber, Zaheer. The Science of Empire: Scientific Knowledge, Civilization, and Colonial Rule in India. Albany: State University of New York Press, 1996. ISBN 0791429199.
  • Lakwete, Angela. Inventing the Cotton Gin: Machine and Myth in Antebellum America. Baltimore: The Johns Hopkins University Press, 2003.

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Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.  Read more
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Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Cotton gin" Read more