Bellis and Morcom steam engine. Cutaway artwork of a front-section through a double-acting steam engine. This design was developed in the 1890s by the British engineers Bellis and Morcom. They used forced lubrication under pressure to prevent the engine seizing up. The cutaway artwork shows the two main pistons at right and left (vertical), with the crankshaft across bottom. The flywheel is at lower left. At lower centre is the forced lubrication oil pump that supplied oil to both pistons.