A rare 19th Century high speed steam engine, which is likely to have powered the fastest torpedo boats used by the Victorian colonial Navy in the 1880s, has been acquired by a museum in Melbourne with the assistance of the National Cultural Heritage Account.

This Thornycroft high-speed compound steam engine is the only known example from a colonial navy torpedo boat in Australia. It is possible that it was fitted to the HMVS Lonsdale or the HMVS Nepean, both of which were Victorian Colonial Navy second-class torpedo boats of the same design that served as part of an escort flotilla for Victoria's Governor in 1884.

During the 1880s and 1890s, J.I. Thornycroft & Co. Ltd. built over a hundred torpedo boats for the British Admiralty and other navies around the world, out of which ten were used in the Australian naval defence and remained in service until 1911.

In their day, torpedo boats such as these were regarded as the pinnacle of marine technology, using innovative technology, construction methods and materials to minimise weight, increase engine power and improve manoeuvrability. This engine is an example of the high‐speed, lightweight marine style of reciprocating condensing steam engine.

Due to their limited use after the end of their operational service, many of these boats were taken apart and abandoned. However, this engine was recovered and installed at Gordon Technical College in Geelong, and is the only such engine understood to have been reused.

This engine has been acquired by the Melbourne Steam Traction Engine Club) with $20,000 assistance from the National Cultural Heritage Account. The Club will be undertaking restoration and conservation work on the engine prior to its public display in the second half of 2022.