Ball and chain

A ball and chain was a physical restraint device historically applied to prisoners, primarily in the British Empire and its former colonies, from the 17th century until as late as the mid-20th century.

A ball and chain believed to date to the 17th century was found in the United Kingdom in 2009. It consists of a sphere of high-grade iron approximately 15 centimetres (5.9 in) across and weighing around 8 kilograms (18 lb). The chain is of some 90 centimetres (35 in) in length and terminates in a leg iron or shackle. The weight of the ball makes it difficult for the restrained person to walk.

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