A slungshot is a maritime tool consisting of a weight, or "shot," affixed the end of a long cord often by being wound into the center of a knot called a "Monkey's fist." It is used to cast line from one location to another, often mooring line. The cord end is tied to the heavier line and the weighted end of the slungshot is thrown across the intervening space where a person picks it up and pulls the line across.
The slungshot was often used as a civilian or improvised weapon. The cord is tied around the wrist, and the weight is carried in the hand or the pocket of the user. To use, the weight is thrown into the opponent's face, rather like a yo-yo. Repeated blows can be landed by "snapping" the slungshot, rather like snapping a towel. A slungshot may also be swung to attack an adversary in a manner similar to that of a flail.
Slungshots were widely used by criminals and street gang members in the 19th Century. They had the advantage of being easy to make, silent, and very effective, particularly against an unsuspecting opponent. This gave them a dubious reputation, similar to that carried by switchblade knives in the 1950s, and they were outlawed in many jurisdictions. They fell out of use sometime in the latter part of the 19th Century.
They were also known as "slingshots," but had nothing to do with what is now known as a slingshot. Many jurisdictions' laws against "slingshots" were actually meant to refer to slungshots.
They were also used in China and Japan, under different names. One variant was called "loaded sleeves," where a pair of long, flowing sleeves had weights concealed in them. According to Robert van Gulik, the reputation of "loaded sleeves" saved some Western nuns during an anti-Western uprising in China; they were cornered by a mob, thought they were going to be killed, and raised their hands to Heaven to pray. Suddenly, the cry went up: "They've got loaded sleeves!" The Chinese had seen their breviaries, which they carried in the sleeves of their robes, and thought that this meant that the nuns were dangerous. A path opened through the crowd, and the nuns escaped.