Channel Tunnel

Channel Tunnel, a proposed tunnel beneath the Straits of Dover, connecting Dover on the English side with Sangatte, near Calais, on the French side. The scheme was under discussion as far back as 1867, and has had the influential support of the late Prince Consort, Lord Beaconsfield, Mr. Gladstone, and others. Sir Edward Watkin, Bramwell, Low, Brady, Hawkshaw, and other engineers have given favourable opinions. The continual delays in the completion of the undertaking are mainly due to English hesitation for military reasons. The successful engineering of the tunnel seems assured, for the whole length of 23 miles could be cut along the bed of old grey chalk, impervious to water and well adapted for easy boring, which lies beneath the upper chalk bed of the Straits. A multitude of soundings have shown the continuity of this gray chalk without fault or erosion from one side to the other. Experimental cuttings at both ends have been made successfully for a mile or two under the sea, and the engineers report that very little water is encountered, this being fresh or brackish. The necessary pumping is, therefore, very slight. The tunnelling is rapid and easy, effected by the compressed-air boring machine, and no timber stays are required. Two single-line tunnels are proposed to begin with, one to ventilate the other. The line is to be worked by compressed-air engines. The inclusive estimated cost is £4,000,000.