UNDER THE CHANNEL.

Lyttelton Times, Volume CXV, Issue 16558, 23 May 1914, Page 2

UNDER THE CHANNEL.

A TUNNEL TO FRANCE.

IMPERIAL DEFENCE COMMITTEE’S REPORT. By Telegraph—Press Association—Copyright. LONDON, May 21. Mr Asquith, questioned in the House of Commons, said that the Imperial Defence Committee would shortly complete its report on tho question of a tunnel under the Channel. SOME DETAILS OF THE PROPOSED WORK. Speaking in London recently, Baron Emile d’Erlanger (chairman of the Channel Tunnel Company) said he understood that the matter, which had hitherto met with the Government’s opposition, was now before the Committee of Imperial Defence. They looked forward with conficlenco to the decision of that body, by which the Government would be guided. From tho entrance at Dover the tunnel would dip under the Channel for a length of twenty-four miles, emerging at Sangatte, near Calais. Twelve miles of tho tunnel would be constructed by the English company and twelve miles by the French company. A large power station would provide motivo power for the trains, as' well as electricity for lighting and compressed air for the purpose of ventilation. The total cost of the whole undertaking, including the construction of the tunnel, purchase of land, payment of interest during construction, and the purchase of rights and plants existing on the English and French coast, was estimated not to exceed £16,000,000, of which £8,000,000 would bo provided by the French company and £8,000,000 by tho English company. Dealing with the strategic aspects of the project, Baron d’Erlanger said the entrance to tho tunnel on tho English side would be in tho valley behind Dover Castle, where it would be fullyexposed both to the direct and plunging fire of tho forts, and it would bo further defended by such additional precautionary devices as the Committee of Imperial Defence might recommend. Even given a successful seizure of the entrance t-o the tunnel, the position would be untenable under the concentrated fire of the forts, and that action would give plenty of time to render tho destruction of the tunnel more permanent. The holding of the mouth of the tunnel by the enemy for a short timo would be of no assistance 1 whatever to the invaders, inasmuch as to transport an army corps by means of tho tunnel it would be necessary for them to hold the surrounding country for many miles inland, and to have at their disposal trucks and .sidings in which to stable tho empty trains. The bogey of invasion by an act of surprise might, therefore, be dismissed—as it was dismissed to-day by the best military critics—as a chimera.

It might be made part of the convention with France that tho only power-station working the tunnel should be under the command of tho Dover forts, near Dover itself, so that', if it were blown up, the traffic would be interrupted. Furthermore, the tunnel could be flooded, and it would take months to pum.pi it dry, while tho land approaches could be destroyed over a considerable distance, so that it would occupy a year or more to repair the damage. "What, then,” said Baron d’Er-

langer, " were the great strategical advantages which made tho tunnel no longer a danger, but a strategic necessity for England? We must at any moment be prepared to concentrate a large portion! of our naval forces upon tho pursuit' and destruction of an enemy, and we Flight have to leave onr shores partially unguarded by our fleet What, then, of our food supplies ? V\ ere we to be starved into surrender? " With tho Channel Tunnel once constructed, we could dismiss this .consideration from our calculations in, the case of any enemy except France. Our food supply would be assured and our fleet untommellled m the fulfilment of its primary 'duty—the finding and destruction of the enemy. He thought the tunnel would capture at least 65 per cent, of the Continental passengers, who at the normal rate of yearly increase would number 2,000,000 at its opening if construction were at once begun. At ft- fftie of tell shillings per head that would secure an income of £650,000. Tho transport of luggage would add ten per cent., or £65,000, and the postal service a further £40,000. .. , It was not too sanguine to put the goods traffic at £BOO,OOO, and this would give a total of £1,505,000, while the total working expenses would not exceed £420,000 per annum, leaving a net profit of £1,135,000 on a capital of £16,000,000. In this estimate, however, no account was taken of the increase in passenger traffic which would result from the construction of the Channel Tunnel, and if they were to transport 3,000,000 passengers in a year, it was easy to see how enormously the profits would be swelled, though the fares would bo substantially reduced. Sir Francis Fox, engineer to the London "Tubes,” who dealt with the technical aspects of the tunnel, said the grey chalk through which it would be bored was an excellent material for the purpose. The main tunnels would consist of two single-track circular "tubes,” each 18ft in diameter, and thus large enough to accommodate therolling stock of the British and French main lines, except' their. locomotives, for which would be substituted electrical locomotives. Including the junctions with tho main lines in England and France, the total length of each tunnel would be thirty-one miles, the actual length under water being twenty-four miles. The tunnels would be thirty-six feet apart, lined throughout by cast-iron segments, and covered with cement to prevent leakage into the tunnels and preserve the plates from corrosion. As-

suming that seventeen yards per day could be bored for six days per week, the annual progress would be about three miles at each face, so that the work would occupy four years. Ventilation would be secured by blowing air in the direction in which each train was travelling. To keep the tunnels pure and fresh it would bo necessary to supply 45,000 cubic feet' per minute on each line of way, travelling at a velocity of, six feet per second, which was equivalent to a very light breezo.