Mughal Empire. The incorporation of the worm gear and crank handle into the roller cotton gin led to greatly expanded Indian cotton textile production during the Mughal era. It was reported that, with an Indian cotton gin, which is half machine and half tool, one man and one woman could clean 28 pounds of cotton per day. With a modified Forbes version, one man and a boy could produce 250 pounds per day. If oxen were used to power 16 of these machines, and a few people's labour was used to feed them, they could produce as much work as 750 people did formerly. United States The Indian roller cotton gin, known as the churka or charkha, was introduced to the United States in the mid-18th century, when it was adopted in the southern United States. The device was adopted for cleaning long-staple cotton, but was not suitable for the short-staple cotton that was more common in certain states such as Georgia. Several modifications were made to the Indian roller gin by Mr. Krebs in 1772 and Joseph Eve in 1788, but their uses remained limited to the long-staple variety, up until Eli Whitney's development of a short-staple cotton gin in 1793. Eli Whitney's patent Eli Whitney (1765–1825) applied for a patent of his cotton gin on October 28, 1793; the patent was granted on March 14, 1794, but was not validated until 1807. Whitney's patent was assigned patent number 72X. There is slight controversy over whether the idea of the modern cotton gin and its constituent elements are correctly attributed to Eli Whitney. The popular image of Whitney inventing the cotton gin is attributed to an article on the subject written in the early 1870s and later reprinted in 1910 in The Library of Southern Literature. In this article, the author claimed Catharine Littlefield Greene suggested to Whitney the use of a brush-like component instrumental in separating out the seeds and cotton. To date, Greene's alleged role in the invention of the gin has not been verified independently. Whitney's cotton gin model was capable of cleaning of lint per day. The model consisted of a wooden cylinder covered by rows of slender wires which caught the fibers of the cotton balls. Each row of wires then passed through the bars of a comb-like grid, pulling the cotton fibers through the grid as they did. The comb-like teeth of the