November 1861: Chalmers' under Channel railway

Over the years The Engineer has reported on several schemes to connect the UK to mainland Europe and, as we know, only one project has been successful so far. 

Tunnels and bridges have been proposed and in 1880 work started on experimental tunnels in Folkstone that were dug by hand and an early tunnel boring machine.

Nineteen years earlier, The Engineer reported on how a certain James Chalmers of Montreal had ‘patented the means whereby he proposes to open a railway communication under the channel.’

Chalmers’ idea was somewhat unique in that he’d connect sections of tube and submerge them, rather than dig a tunnel.

The Engineer said: “The shape and form of the tubular roadway may be varied, but it is preferred that such tubular roadway for deep water should be of a circular section, having a rectangular inner way formed therein, as thereby the pressure of the water at great depths may be divided between the tubes by allowing the leakage of the outer or circular tube to collect between it and the inner one, until it obtains such pressure as the inner or square tube may safely carry, then drawing it off through valves into the inner tube, thus relieving by reaction the pressure on the outer or circular tube.