<P> Between the 12th and 14th centuries, dual - roller gins appeared in India and China . The Indian version of the dual - roller gin was prevalent throughout the Mediterranean cotton trade by the 16th century . This mechanical device was, in some areas, driven by water power . </P> <P> The worm gear roller gin, which was invented in the Indian subcontinent during the early Delhi Sultanate era of the 13th--14th centuries, came into use in the Mughal Empire some time around the 16th century, and is still used in the Indian subcontinent through to the present day . Another innovation, the incorporation of the crank handle in the cotton gin, first appeared some time during the late Delhi Sultanate or the early 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 . </P> <P> 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 . </P> <P> 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 . </P>

Where was the first model of the cotton gin made