American inventor Eli Whitney (1765–1825) is credited with developing the cotton gin, a machine that removes cottonseeds from cotton fibers. A simple cotton gin (called the churka ) dates back to ancient India (300 b.c.). But Whitney's gin would prove to be far superior. In 1792 Whitney, who had recently graduated from Yale University, was visiting the Georgia plantation owned by Katherine Greene, widow of American Revolution hero General Nathaniel Greene (1742–1786). Whitney observed that short-staple (or upland) cotton, which has green seeds that are difficult to separate from the fiber, differs from long-staple (also called Sea Island) cotton, which has black seeds that are easily removed. The latter was the staple of American commerce at the time.
In 1793 Whitney, who is described as a mechanical genius, completed an invention that could be used to clean bolls of short-staple cotton of their seeds. He patented it the next year. The machine worked by turning a crank, which caused a cylinder covered with wire teeth to revolve; the teeth pulled the cotton fiber, carrying it through slots in the cylinder as it revolved; since the slots were too small for the seeds, they were left behind; a roller with brushes then removed the fibers from the wire teeth.
The cotton gin revolutionized the American textile industry which was then but a fledgling concern. The increase in the production of processed cotton was phenomenal. One large gin could process fifty times the cotton that a (slave) laborer could in a day. Soon plantations and farms were supplying huge amounts of cotton to textile mills in England and in the Northeast of the United States where in 1790 another inventor, British-born industrialist Samuel Slater, had built the first successful American water-powered machines for spinning cotton cloth. Together the inventions founded the American cotton industry. Whitney struggled to protect his patent. His problem was getting Southern courts to enforce his patent. The courts, dominated by plantation interests, refused in every case to uphold his patent.
For the southern slaves, Whitney's invention was a disaster. Prior to the invention of the cotton gin a consensus had prevailed that slavery would fade away. There were the moral objections to slavery (which, however, for the first 250 years of its existence in colonial and early republican America, never seemed to be quite persuasive enough to put an end to it). But there was also the fact that slavery was inefficient when applied to most kinds of agriculture or skilled production. Cotton, however, was a labor-intensive crop requiring large gangs of workers moving through the fields at different times in the growing cycle, planting, hoeing, and harvesting. With the invention of the "gin," cotton suddenly became a highly profitable cash crop. Although the Constitution had stipulated that the importation of slaves would end in 1808, now the price of slaves rose and the slave system was reinvigorated at the very time when it was being outlawed in most of the rest of the world.
See also: King Cotton, Samuel Slater, Slavery, Textile Industry
The hand labor required to prepare cotton for market served as a brake on its production and profitability. Each ball of cotton fiber had numerous seeds embedded in it, and they had to be either picked out by hand or run through a roller gin. The term "gin" arose as an abbreviation for "cotton engine." A roller gin consisted of a hand crank and two grooved rollers. A roller gin operator could turn out about five pounds of cotton fiber in a day's work—in contrast to one pound a day processed by hand—but the gin did not completely clean the cotton. It had to go through an additional process, called "bowing," to shake out dirt and debris.
The two-roller gin had been in use since its unknown early origins—possibly the twelfth century—in India and China and was imported by British colonists to North America. As cotton thread spinning was mechanized in England, planters in the southern colonies sought to increase cotton production. To that end, a Louisiana planter designed an improved roller gin in 1742, and several other men made further improvements, including treadle operation, between 1772 and 1790. The improved roller gins had higher capacities—peaking at more than one hundred pounds of fiber output a day—but also crimped the fibers.
The mechanically inclined New Englander Eli Whitney, recently graduated from Yale College, was employed as a tutor in Georgia when he turned his talent to the ongoing problem of removing seeds from cotton. Barely a year after his arrival in Georgia, Whitney in 1793 created a working model of a hand-cranked mechanical device that used a rotating, wire-toothed cylinder to remove cotton seeds. As the fibers passed through the metal teeth, the teeth caught and removed the seeds; the teeth also cleaned and combed the fibers. But the design was not without drawbacks: the wire teeth occasionally broke off and became entangled in the cotton.
American planters eagerly embraced the new cotton gin design and planted more acreage to cotton, reassigning slaves from ginning to planting and harvesting the vast new fields. As a result, cotton production in the United States expanded tremendously, more than tripling in the five years following the introduction of Whitney's design.
Although Whitney had worked in secret and then filed for a patent on his invention in 1794, the new American patent law was not yet enforceable, and he reaped little financial reward. Also, he was unable to produce enough machines to meet demand. Planters complained that Whitney charged too much and encouraged local mechanics to build copies. The early theft of Whitney's prototype from his workshop eased their way.
Once the secret of Whitney's design was out, manufacturers throughout the nation seized the opportunity to enrich themselves by producing cotton gins. Lawsuits and competing patents proliferated over the ensuing decades. Several gin manufacturers improved the design, replacing the breakable wire teeth with sections of fine-toothed saw blade, creating the so-called saw gin. Whitney himself eventually adopted saw blades in his later gins. Saw gin producers claimed daily output capacities of close to one thousand pounds of cotton fiber.
Over time, cotton spinning machinery in America and Britain was adapted to the shorter fiber lengths turned out by saw gins. In 1792, the year prior to Whitney's invention, America exported an estimated 138,000 pounds of cotton to England. In 1794 cotton exports surged to more than 1.6 million pounds. In 1826 cotton exports topped 200 million pounds.
See alsoCotton .
Britton, Karen Gerhardt. Bale o' Cotton: The Mechanical Art of Cotton Ginning. College Station: Texas A&M University Press, 1992.
Lakwete, Angela. Inventing the Cotton Gin: Machine and Myth in Antebellum America. Baltimore: Johns Hopkins University Press, 2003.
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.
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.
In 1793, American inventor Eli Whitney (1765–1825) invented a machine that made harvesting cotton much easier. His cotton gin enabled a laborer to separate a lot of cotton from the seeds with little effort. A laborer
working by hand could once expect to produce only one pound of cleaned cotton per day. With the help of a cotton gin, fifty pounds could be cleaned in a day.
Whitney did not invent the very first machine to separate cotton from its seeds. The machine that existed at that time, however, did not work on all types of cotton. It crushed the seeds of the green-seeded cotton that grew easily throughout the South, staining the product. Black-seeded cotton, which was easy to clean, only grew in the southern coastal areas. As a result, the South's production of cotton was limited by the inability to easily clean the cotton that grew best inland from the coast.
New processes for making cloth created a growing demand for cotton, including in Europe. Knowing that a machine capable of processing the green-seeded cotton could help growers meet that demand, Whitney turned his focus to making one. Within a few months, he had perfected a design. He obtained a patent in 1794, though he would benefit very little from the rights. Many imitations of his design arose throughout the South, and Whitney had little success protecting the patent in court.
The effect of Whitney's cotton gin was vast and unforgettable. Cotton quickly became the dominant crop in the South. Its entire economy was revitalized as green-seed cotton became a profitable crop. The United States became a powerful global force as the crop grew. Southern exports of cotton filled more than half of the world's demands.
The downside to the cotton boom was the effect it had on prolonging slavery in the United States. The crop demanded constant attention, and the large fields required many laborers. While Northern states moved toward emancipation at the end of the eighteenth century, the cotton boom cemented the South to slavery in a way that other crops did not.
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.