Two R. & H. Green & Silley Weir mechanical engineers at work in the engine room on board an unknown ship. They are inside the crankcase of a diesel motor, and are working on bearings marked A1 and F1 and an item with "No. 1 Aft" marked on it. One of the men appears to be using a large spanner. The location may be any of the docks in the Port of London or in Falmouth.