An automatic lubricator is a device fitted to a steam engine to supply lubricating oil to the cylinders and, sometimes, the bearings and axle box mountings as well.[1] There are various types of automatic lubricator, which include various designs of displacement, hydrostatic and mechanical lubricators.
^"Lubrication". Handbook for steam locomotive enginemen. London: British Transport Commission. 1957. pp. 126–128. OCLC505163269.