Petrol-electric car, based on Fiat 8 H.P. open two-seater, 1927. The clutch and gearbox have been replaced by H K Whitehorn with the Tilling-Stevens petrol-electric transmission system which was patented by W.A.Stevens and P.F. Smith between 1906 and 1916. This system consists of a petrol engine driving a dynamo that supplies current to a motor which drives the rear wheels through a shaft and bevel arrangement. Whitehorn worked for Tilling-Stevens as their Chief Electrical Engineer, and in 1927 – after leaving Tilling-Stevens – he converted this car for his own use. In December 1911, a Tilling-Stevens bus had been launched in London. This was the beginning of a very lucrative venture. In addition to buses, the firm produced petrol-electrical generating devices. With advances in mechanical transmissions, and the advance of diesel for commercial vehicles, the petrol-electric transmission lost favour. Tilling-Stevens discontinued regular production in 1929.