DOUBLE-ACTING STEAM ENGINE. The Single-acting Engine unfit to impel Machinery. -- Various Contrivances to adapt it to this Purpose. -- Double-Cylinder. -- Double-acting Cylinder. -- Various modes of connecting the Piston with the Beam. -- Rack and Sector. -- Double Chain. -- Parallel Motion. -- Crank. -- Sun and Planet Motion. -- Fly Wheel. -- Governor. 91