Saw gins are not adapted to long-stapled cottons, such as Sea Island and Egyptian, which are generally ginned by machines of the Macarthy type.
Saw gins do considerable damage to the fibre, but for short-stapled cotton they are largely used, owing to their great capacity.
Opposed to the various types of roller gins is the " saw gin," invented by Eli Whitney, an American, in 1792.
Since about 1875 the Russians have fostered the industry, introducing American Upland varieties, distributing seed free, importing gins, providing instruction, and guaranteeing the purchase of the crops.
Moveable gins were tried for a time in some places; they were dragged by traction engines from farm to farm, like threshing machines in parts of England, but the plan proved uneconomical because, among other reasons, farmers were not prepared to meet the cost of providing facilities for storing their cotton.