THE CHANNEL TUNNEL

Dominion, Volume 12, Issue 59, 4 December 1918, Page 5

THE CHANNEL TUNNEL

AMERICAN ENGINEER'S OFFER i I PLAN FOR HIGH-SPEED ! CUTTING . i The idea of a tunnel beneath the Eiig- j lisli Channel to connect England and j France was frequently discussed, iii'.nre- I war days; but there were always inter- I national considerations which stood iu ■ the way of it being carried out. During > the war the Allies have devoutly wished j such a tunnel existed, and it is> known i that the lcasibility ut rapidly construct- j ing one lias been seriously considered. | One scheme, that was investigated was j lrom -Mr. ,1. K. lleiicken. a civil en- : jjineer ol Manhattan, li.ti.A., and was ; laid before the Allied Governments in \ May hist. What decision was arrived . ut is not known. The following article \ dealing with, the subject appeared in the ', "New ITork Herald":— . ... ' j In a statement recently issued, Mr. . Heiickcn says that he is the inventor of | tunnelling machinery that would make it j possible to havo four lunncls in opera- j tion within a few months. Mr. Hencken says in parti— "It is expected that each tunnel can ; bo cut at tha rate of ICO feet an hour j with eight machines, working four from > ei-.cli shore, the time being required will I be thirty-live days. The approaches can j be c.iit b.v another set of eight machines ! working at the .■■ame time. The tunnels ; as planned would be of sufficient width j to provide a roadway in addition to the j trackway in each tunnel, if desired, so| that motor lorries could be used addi- i tionally to the- trains ironi base to base j without breaking bulk." j That Germany is alive to the enormous ! military advantage to the Allies of such j a connecting tunnel is manifest from a i recent statement at Professor Ivrueck- j maun, of iluenster. Professor Krueck- i maun said that one of England's (irsfc j acts after the war would be to "con- J struct the famous tunnel from Dover lo i Calais, which would make Germany's : submarines valueless, and place Ger-1 many at the mercy of England in the i second war." '

Under the old methods of excavation . the proiect, it is estimated, would take th.ee years and cost .£60,000,000. The ; scheme was first taken under considers-; tion by the British Governnient last I May, when the British mission, headed : by' Mr. A. J. Balfour (Foreign Minister); went to America. At that time Mr.; lieiickou received the fallowing letter : from Mr. Inn Malcolm, Mr. BaU'our's i secretary:— . ■ "Mr. Balfoiir-nsk-i me to thank you | for your letter of May 1C and to gay I in reply that your suggestion nlready; has been brought to his notice fince he i lias boon in America, and llinl the mat-• ier is under the close consideration of ' the British Cabinet in London." '

Mr. Mencken's scheme also has been \ brought to tho attention of President: Wilson, Mr. Newton ]). Baker (U.S. i Secretary for War), ad Secretary Lan- ] sing (U.'S. Secretary of .State), Brigadier- j General William H. Bixby, U.S.A. (re-; tired), formerly chief of engineers; Mr. j R. ].'. Clarksoii, professor of engineering! at Acadia University, in Canada, Mid, Mr. Worlhington SI. Jacobus, consulting, engineer mid secretary and treasurer of ; the New Jersey Ship Canal Commission: and chief engineer of tho Meadows Im-1 Iprovement Company. | T'he following oiler was made by Mr.) Hencken (o the United States, British | and French Governments:— j

"In compliance with requests as ex-j pressed by the President of Hie United j States and the State, AVar, Navy and] Commerce Departments and the embas-J sies and Commissioners uf France'and; Great Britain, I have prepared plans: for a brief statement of my tunnelling j system, which will enable these tunnels; til bo constructed, joining England and | France, ready for train service, in a! few months. This will release most of! the shipping now used between England i and the Continent, thus making morel ships than can be built in all the! world's shipyards in several years. The j work will be executed by British, French: and American engineers of the highest j standing, directed by Colonel Bogart.i civil engineer, of New York and London.; Any companies or individuals having: rigtite, property or data pertaining to these tunnels will be adequately com-: pensated. • . "Under the old methods and with the! present high cost of labour and mater-, ials the cost of the four tunnels pro-, posed by me would be in the neighbour-; hood of '..£60,000,000, and take eight years, to construct, the estimated cost prior to : the war for only two tunnels having been; from .£16,000,000 to ,£20,000,000. It aj franchise is granted to me I will start the work at once and undertake to i finance the enterprise, issuing.bonds to. an amount, to bo agreed upon m confer-; ence, which I will retire in a few years,: and then deliver through our President; these tunnels free and clear of all en,; oumbrances as a gift from America to ; In° P a'detailed account of the working: design of the tunnelling, Mr. Hencken: tunnel will preferably be located' at considerable depth below the bed _oti the channel to avoid possibility of ni-j jury from above, and my recommenda-; tion is 100 feet, as tbs minimum depth, below tho channel bed. My. reconiinenda-, tion is that four tunnels be.driven, two at the 100 feet depth, and the other two somewhat lower, to be used as drainage, tunnels additionally 'to their use as; traffic tunnels. The tunnels may be, cylindrical in section, but if road space is desired alongside-of the railway track, the lower half of the tunnel may be out, square or rectangularly.', _ ! Mr. Heucken's description of bis tunnelling machine is as follows-.-. . "The machine is moved forward, with, all appurtenances connected with it, uj< a system of caterpillar tracers which permit the axis of the tunnel to.follow a. curvo of 100 feet radius and to..nme horizontally, obliquely, or vertically.: The boring or cutting is et-, fected by a series of .swing-, ing hammers rotated at a peripheral; spied of about five hundred teet per, second, or greater or . lc VVSin7 and carried in a revolving head, waking from one to ten revolutions P«™t e :: These hammeie strike several bund d, thousand blows per minute <» tb« face, to bo excavated, each blow 1 mvi.ng th_e, speed and power of a 3-inch »lid Pio-. j ctile. They will pnlver.se and break up the material into particles from fie ; nehes in greatest dimension to impalpable powdSr. There are two ;sets of, hammers striking forward y ngiunst Ita face to be excavated, and as. the ne.id. -evolve, covering the wholeof that face, except the outer margin, this'being excavated and finished >»' l »» men rotating in P aiies P«allel to 9 face to be excavated. These lolatint, hammers not only' pulverise am break up the material to be excavated, but carry the material to conveyors. 1 I ey, Si enclosed In housings to developtliis action, and they carry lh« meenalq a bell conveyor. As it falls upon this belt conveyor it is thoroughly .vetted, and the belt conveyor e«™« 11 , 10 , h 3 main conveyor, which carries it to the desired point of delivery. j ■ : "This point of delivery may be at tie face of the cliffs overlooking the Chan-, ne a a point where filling would be unobjectionable, and located in such relation to the tunnel work as not to d sclose the locality of that work. ihuS tho problem of taking care ot the great amount of material excavated can J* simplified, as, indeed, inucn of the rn.ij tcrial would be carried away ;by tide Tho head conveyor belt will niovu along with the tunnel head as the work of excavation proceeds. The main conveyor belt will also move along with the head, two trackways for supporting the belt, one on each side of the tunnol; being built as the work proceeds, lho main conveyor belt will be lengthened ■at intervals'by adding sections, and this can readily be done without stopping i the belt. 'Tlis (lumping point will be fixed the belt always extruding beyond it. The total length between the two belt wheels of this conveyor will be at the utmost about 70,000 fv>el. The belt jwill be driven by electric motors placed i\it intervals of 500 feet. The belts will be built up of steel sections. This nieJ I hod of removal of Ihe excavated ma-| terial' prosonls no difficulties, .the conveyor bolt method boms standard engiib ee'ring. The tunnel head includes A| lining , shield to act as a mould tor n concrete lining and the concrete may bq forced in under pressure to fill all crack* as well as provide a lining. j