Working model, scale 1:32, of a pair of side-lever engines from the H.M.S. 'Dee', (1832), mounted on wood hull section, designed by Henry Maudslay and made by Maudslay, Sons and Field Limited, Lambeth, London, England, 1827-32.

This superb item is one of the finest model marine engines in existence, made by engineer Henry Maudslay, a renowned user of models in mechanical engineering practice. Its provenance is excellent, having been acquired from Maudslay, Sons and Field in 1900; a sketch survives in Ediburgh City Archives of Maudslay sitting in his private workshop with the model. The side-lever engine was introduced by Boulton, Watt & Co., and its design gave a low centre of gravity. The model is particularly noteworthy for its fine finish particularly the gothic framing supporting the crankshaft, which in marine engines was ascribed to Marc Isambard Brunel.

The paddle ship 'Dee' was a mail packet used for post office work, built 1827-32. The cylinders were each 54 inches diameter by 5ft stroke, supplied by tubular boilers with steam at 8 pounds per square inch. The engine drove two paddle wheels each 20 feet in diameter, giving a speed of around 8 knots.