An insulated mountain of ice, whether on Arctic lands or floating in the sea. Some have been known to be aground in 120 fathoms water, and rise to the height of 150 feet above it. Cook's obtaining fresh water from floating icebergs was not a new discovery. The Hudson's Bay ships had long made use of it; and in July, 1585, Captain Davis met with ice "which melted into very good fresh water."