Laurence Apel was propelled across the deck of a barge which was transporting construction materials across the East River.
In order to move the vessel, a heavy eighty-foot-long anchor rod had to be lifted from the water by a crane, and a 125-pound steel pin placed in a hole to lock the anchor in place. Apel was inserting one of those steel pins when the crane prematurely released the anchor, causing the pin to pop up like a "seesaw," "snapping" the guy's arm and "hurling" him across the boat.
When he later sued, the New York County Supreme Court found the City of New York liable for the man's injuries.
Since no adequate safety measures were in place to guard against the unchecked descent of that "very heavy" anchor rod, the Appellate Division, First Department, agreed with the lower court's determination. (It also didn't think Apel was responsible for what transpired.)
Damages aweigh! 
To view a copy of the Appellate Division's decision, please use this link: Apel v. The City of New York