Explosive lances were designed to kill a whale by exploding inside its body. Many different types were invented in the late 19th century. When they worked properly, they were extremely efficient.
They could either be shot out of guns or set at the end of darting guns. These devices resembled harpoon handles, to which the explosive lances were fixed. Once a plunger touching the whale’s skin moved a specific length, it triggered an explosive charge that shot the lance into the whale’s body.