Model of inverted compound steam engine fitted with Hackworth's valve gear, scale 1:6, original made by the Brush Co for the City Road Substation of the County of London Electric Supply Co.

This fine model was built by the high quality modelmakers T and C Coates of Wallington, Surrey, and represents one of the County of London Electric Supply Co's reciprocating engines commisssioned for their City Road sub-station, London. This station, together with its sister at Wandsworth, had a combined generating output of 300kW. They represent the relatively small scale of early electricity generating plant - subsequent plants making use of the Parsons turbine instead of such reciprocating engines would be expanded up to 3960mW output - over 13,000 times larger than the County of London Electric Supply Co's combined output.