Heap-sand
The common sand on the foundry floor. When a moulder is using a certain quantity of sand every day for filling a set number of flasks with, he usually collects it in a heap close by, and designates it as heap-sand; in contradistinction to the facing-sand or new-sand employed in the immediate vicinity of his pattern. See FLOOR-SAND; OLD-SAND; FACING-SAND. Hearth is that part of a smelting-furnace where the ore accumulates and is finally separated from the impurities which may be present in the ores. It is situated at the bottom of the furnace, a little above the mouth of the tuyeres. The term is also applied to the bottoms of finery, open-hearth, and reverberatory furnaces, where the metal is exposed to the action of fire. See BLAST-FURNACE.