The Southern Region introduced an electric locomotive (later class 71) in 1960 capable of drawing power from both the third rail and from overhead catenary - which was only provided in yards.
These were followed in 1966 by what became class 73, unusually they were powered by both electric motors, with pick up from the third rail, and by diesel engines. So they could work in yards and on other railways where there was no third rail. Very successful some continue in use.
© Paul Bartlett's Photographs