Simplex 264 264 is a very early example of the famous 'bow framed' design of 20hp Motor Rail 4wPM locomotives built for use by the British Army in France in 1916. Builder's number 264, it carried the number LR 264 in wartime service.
Later used at the British Nuclear, Biological & Chemical Research Establishment at Porton Down, scene of germ warfare experimentation, it was obtained for use at a peat bog in Somerset around 1952. Rescued by Ian Jolly for preservation in 1977, it came to the Welsh Highland Heritage Railway in May 1997.
The locomotive currently has a Dorman petrol engine of the type originally fitted.
See the WHHR site for more information.