On page 675 of The Graphic of 18 April 1914 is a full page drawing of an imagined Channel Tunnel.
How the King may travel to Paris - in Future: What the Conqueror did not foresee
Those looming ships and swarming monoplanes don't make it look as if the tourists are particularly friendly. There's a touch of the vortex in the drawing.
Have a look at the artist's signature in the bottom left:
Although without the cubist angularity the sense of the unstoppability of technology is quite pronounced - and explicit, if a tad optimistic, in the accompanying text:
Once the Channel Tunnel is complete - and sooner or later it is bound to come - the tourist bound for France will have the choice of travel by land, sea and air.