Article found in The Illustrated London News magazine of 31 January 1914. Photographs by G.P.U.
The General Post Office is about to start its own tube railway to facilitate the handling of mail matter in London; this in addition to the numerous miles of pneumatic tubes already in use. The first section of the new line will cover about 6,25 miles, from Paddington to Whitechapel; will all be underground, and will consist of two tracks, each of two-feet gauge, in a tunnel with an internal diameter of nine feet, except near stations where there will be two approach tunnels each seven feet in diameter. At the stations there will be two tunnels each twenty-one feet and a-half inches in internal diameter, and there will be provision for two tracks and a platform in each tunnel. At three of the stations - West Central District, King Edward Building, and Mount Pleasant - the tunnels will be twenty-five feet in internal diameter and there will be two tracks. The line will be operated by electricity and the trains will be worked automatically.
The author of the article and the photographer are unknown. Since it is published far more than 70 years ago, both are believed to be in the Public Domain.