During the 1920s and early 1930s the Underground Group produced various versions of Underground or ‘Tube’ maps for public distribution. These included folding paper maps that were useful but difficult to handle ona crowded platform or train. So a small stiff card folder was issued for many years with a ‘sketch map’ of the lines showing only minimal topographical background so as to make the diagram easier to read. The lines still, however, to an extent followed the geographical nature of the lines leading to the perception of crowding in the central area and the difficulty of showing station names. These issues were to be addressed in the early 1930s by the Beck design for the diagram. F H Stingemore was an Underground employee who also undertook other graphic work for the company. The diagram’s key shows the pre-Underground Group’s ownershipship of companies and lines alongside the independent Metropolitan Railway. In 1933 this was to change when all were brought under the ownership of the new public corporation known as London Transport.
This edition looks to date just a year or so before that merger as the extensions of the Piccadilly line shown in both north and west London came into use in 1932/33.

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