that it covers the firebox crown sheet at all times – otherwise, the latter will overheat and weaken, and a boiler explosion may result. The fireman also assists the driver by spotting signals and keeping a good look out when not attending to the boiler. At the shed after the day's work is done, the fireman will fill the boiler with water and either bank or dump the fire (i.e. extinguish the fire) or leave the fire to die back according to company policy, apply the locomotive handbrake and if required chock the driver wheels to prevent the locomotive from moving while it is unattended. Gallery Road locomotive firebox Road locomotives, such as traction engines, usually had fireboxes similar to those on railway locomotives but there were exceptions, e.g. the Sentinel steam waggon which had a vertical water tube boiler. Stationary boiler firebox There were, and are, many different designs of firebox for stationary boilers. In flue-type boilers (e.g. the Lancashire boiler) the flues themselves form the firebox. In water-tube boilers, the firebox is usually a firebrick-lined compartment below the water tubes. Marine boiler firebox In marine boilers there are also various types of firebox. The main distinction is, again, between fire-tube types (e.g. the Scotch boiler, with internal firebox) and water-tube types (e.g. the Yarrow boiler, with external firebox). See also Firetube boiler Flue Fusible plug References Steam boiler components Steam locomotive fireboxes Fireplaces