Such are the essential passages of the report which, in 1868, was submitted to the Government of the Emperor Louis Napoleon, and was made the subject of a special commission appointed by the Emperor to inquire into the subject in all its bearings. The commission presented its report in 1869, and these are the chief conclusions contained in it:
I. The commission, after having considered the documents relative to the geology of the Straits, which agree in establishing the continuity, homogeneity, and regularity of level of the grey chalk between the two shores of the Channel,
Are of opinion that driving a submarine tunnel in the lower part of this chalk is an undertaking which presents reasonable chances of success.
Nevertheless they would not hide from themselves the fact that its execution is subject to contingencies which may render success impossible.
II. These contingencies maybe included under two heads: either in meeting with ground particularly treacherous—a circumstance which the known character of the grey chalk renders improbable; or in an influx of water in a quantity too great to be mastered, and which might find its way in either by infiltration along the plane of the beds, or through cracks crossing the body of the chalk.
Apart from these contingencies, the work of excavation in a soft rock like grey chalk appears to be relatively easy and rapid; and the execution of a tunnel, under the conditions of the project, is but a matter of time and money.
III. In the actual state of things, and the preparatory investigations being too incomplete to serve as a basis of calculation, the commission will not fix on any figure of expense or the probable time which the execution of the permanent works would require.
The chart, Fig. [185], and the section, Fig. [186], will give an idea of the course of the proposed tunnel, which will connect the two countries almost at the nearest points. The depth of the water in the Channel along the proposed line nowhere exceeds 180 ft.—little more than half the height of St. Paul’s Cathedral, which building would, therefore, if sunk in the midst of the Channel, still form a conspicuous object rising far above the waves. But the tunnel will pass through strata at least 200 ft. below the bottom of the Channel, rising towards each end with a moderate gradient; and from the lower points of these inclines the tunnel will rise slightly with a slope of 1 in 2,640 to the centre, or just sufficient for the purposes of drainage. On the completion of the tunnel a double line of rails will be laid down in it, and trains will run direct from Dover to Calais. Companies have already been formed in England under the presidency of Lord Richard Grosvenor, and in France under that of M. Michel Chevalier, and the legislation of each country has sanctioned the enterprise. Verily the real magician of our times is the engineer, who, by virtually abolishing space, time, and tide, is able to transport us hither and thither, not merely one or two—almost like the magicians we read of in the “Arabian Nights,” with their enchanted horses or wonderful carpets—but by hundreds and by tens of hundreds.
Fig. 185.—Chart of the Channel Tunnel.