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BLACKWALL RAILWAY, FENCHURCH STREET. About 4½ miles in length; built upon arches, and worked originally by two pair of stationary engines - one of 400 horse-power at the Minories station, and one of 200 horse-power at Blackwall. The ropes (3 5/8 inches in circumference, or 1¼ inch diameter) were made of wire formed of four strands, (each composed of 42 wires), and extended along the whole length of the railway, guided by grooved pulleys, and coiled alternately at each extremity on drums. The expense of working the engines and ropes was about fourteenpence per train per mile. The machinery was made by the Messrs. Maudslay. The carriages (attached to the ropes by "grips") travelled alternately along either line, and the signals for starting and the general working of the line were given by the electric telegraph. But this was found an expensive process. The stationary engines therefore discontinued early in 1849, and the usual railway engines introduced in their stead. The portion of the line from Fenchurch-street to the Minories, a distance of only 450 yards, cost 250,000l. Boats run from Blackwall to Gravesend every half hour or oftener, throughout the season, performing the passage from the London Terminus to Gravesend in 1¾ hours with tide, and 2¼ hours against it. Tickets are issued at the stations to clear the whole distance; and on a fine day the excursion is a very pleasant one, with the additional recommendation of being very cheap. Brunswick Wharf, Blackwall, was opened for the reception of packets, July 6th, 1840.

Peter Cunningham, Hand-Book of London, 1850