Abstract: Apparatus for safely plugging a furnace adapted to hold and transfer substantial amounts of molten material, the apparatus including a linkage assembly comprised of generally parallel bars pivotly connected together. A fluid operated cylinder is mechanically connected to the linkage assembly. An elongated bar is supported by the linkage assembly, and a plug is located at one end of the bar for disposal against and removal from a spout structure of a furnace. The cylinder translates the linkage assembly and thereby translates the bar and plug such that the plug can be moved to and from the spout structure. The plug is held against the spout structure under a positive force exerted by the cylinder.