An excellent effort to portray the complexities of the Métro with just two colours. A  wide array of different dashed lines allows 15 lines (the 14 Métro lines plus the Ligne de Sceaux) to be differentiated relatively easily. As a guide for tourists, the map wisely concentrates on the central part of Paris, leaving the stations further out to be listed in neat little call out boxes.

Source: 217lemurs/Tumblr

Paris Metro map from the inside cover of The Blue Guides Short Guide to Paris published by Ernest Benn Limited in 1951. Edited by L. Russell Muirhead.

Inside the book was a fold out map of Paris – although not attached it is presumably intended as part of the book.