A printer’s proof of the first card folder (pocket) edition of Beck’s famous diagram, with edits and corrections marked in his own hand.

Of note is the use of quite ugly and overpowering “blobs” instead of the now-ubiquitous “ticks” for station markers, and the fact that the map has been entirely hand-lettered by Beck, using what he called “Johnston-style” characters. He’s cheated quite a bit with his letterforms and spacing on some of the longer station names.

The Piccadilly line is also shown in what seems to us a very odd light blue, although Beck was simply following established colour conventions from earlier geographical maps. The now-familiar dark blue was in place by the time the diagram was officially released in January of 1933.

Source: Scanned from my personal copy of “Mr. Beck’s Underground Map” by Ken Garland