Hay Rope
Hay twisted into rope to any desired thickness, and used for wrapping core-barrels before the clay and loam is applied, its purpose being to cover the vent-holes in the barrel, and at the same time serve as a medium for carrying the loam. When the molten metal covers the core, the gases generated in the sand enter the hay rope and pass into the barrel through the vent-holes provided. Straw, and meadow as well as prairie hay, are also employed for making these ropes. See CORE-BARREL; ORDNANCE; HAY-ROPE TWISTER.