It could also be the result of the "Wrist Rocket" an aluminum sling
shot which in one piece "wrapped" around the forearm above the wrist,
padded there, and the sling part surgical like tubing which claimed at
close range to have the impact of a small firearm and could shoot a
marble quite far (just saw the Longfellow House on the TV, once
General George Washington's headquarters for 9 months). I think they
are outlawed in some places, as are various martial arts weapons
(hardware) in the Borough of the Bronx, though one of the original
ones, carried by Japanese monks on their journeys, a cast iron hand
fan, would be difficult to outlaw.