Canning Dock, Liverpool

Once part of the Port of Liverpool located on the River Mersey . It was situated in the southern dock system, connected to Salthouse Dock to the south and Canning Half Tide Dock to the west. The dock was opened in 1737 as a protected tidal basin providing an entrance to Old Dock. Having been subsequently enclosed as a wet dock three years earlier, in 1832 it was officially named after the Liverpool MP, George Canning. Canning Dock would have initially served ships involved in the transatlantic slave trade. Read more on Wikipedia 

Joe Passalique walks towards dock in his ramble around Liverpool in Lowry's short story "Goya The Obscure"; "A dockside train … was rumbling… beneath the Overhead Railway bridges in the direction of Mann Island and Canning Dock”.(Pg.278) and Dana Hilliot recalls in Lowry's novel Ultramarine; "with its diminutive engine is rumbling along cautiously beneath the Overhead Railway bridges in the direction of Mann Island and the Canning Dock, ..." (Pg. 70).

Wilfrid Lowry, Malcolm's brother, was in the Royal Naval Reserve based on H.M.S. Eagle (Eaglet) in Canning Dock. See the following posts on Malcolm Lowry @ The 19th Hole for further details:

Q-ships and Ronald Niel Stuart VC, DSO

In addition, to the above post on Q-ships and Uboats - Lowry may have seen a Uboat in Canning Dock in 1918 (as above) which sparked his imagination about the submarine which is featured in Under The Volcano. See following posts for more details:

Q-ships and Ronald Niel Stuart VC, DSO

H.M.S. Tamarisk

Q-Ships Review New York Times

Q-ship on Fox Movietone

Dark Journey 1937