Model of a Fire Hearth for Steam Engines; Model of a device for the mechanical firing of a boiler; a bucket with movable bottom; operated by a handle with a pawl on a gear wheel; is filled with coal through a small door; the bottom is jacked up and the coal is transported from below to the grid; two movable parts of the grid; operated with a lever and prevented from falling back with a pawl on a gear quadrant; each time a part of the contents of the tray is scooped up. 1:10 scale (derived).; Rijkswerf Rotterdam; c. 1840 and/or 1844; wood (plant material); brass (alloy); h 8.8 cm x w 10.6 cm x d 18.8 cm