Model of Joyce's single cylinder pendulous oscillating engine, 1851

This model of Joyce's pendulous steam engine is an oscillating engine, in which the piston rod works directly on to the crank pin and the cylinder rocks in trunnions, arranged with the cylinder vertically above the crank. It is representative of many small engines designed in the nineteenth-century to be suitable for workshops and small factories. The designer, William Joyce of Greenwich, showed one at the Great Exhibition of 1851, claiming for it the advantages of economy of fuel, simplicity, and saving of space. The first claim was specious, the second arguable, but the third was well-founded. The full-size engine would have been built of iron, but whatever it was bult from, it would not have rescued Joyce from the bankruptcy which he fell into in 1854.