From the top down
Taken from first version of London Underground map published in 1933 in which interchange stations are denoted by a ‘diamond’.
Taken from a version published in the late thirties in which interchange stations are denoted by interlinked circles.
Taken from a poster in 1949, which according to Ken Garland, Beck considered his best, and which included the ‘highly successful white line connector for the double and triple stations’.
Extracted from the Graphic Lines Archive – Circa 1978

