ARTHUR'S PASS TUNNEL.

New Zealand Herald, Volume XLV, Issue 13708, 26 March 1908, Page 8

ARTHUR'S PASS TUNNEL.

THE CONTRACTOR ABROA \,

A GREAT UNDERTAKING.

[from our own correspondent.]

LONDON 1 , February 14. YESTERDAY I had an interesting chat with Mr. Murdoch McLean, the contractor for the Arthur's Pass tunnel through the Southern Alps.

" Since my arrival in England on October 22last," said Mr. McLean, "I have necessarily spent a good deal of time looking about me and feeling my way and making inquiries with regard to the machinery and plant that I needed for driving the big tunnel. You know that the object is to get the New Zealand Midland railway through the Southern Alps so as to connect the east and west coasts 'of the South Island— Christchurch and ~\Yestland-~by direct rail. As soon as possible after my arrival in England I went to the Continent to see all the largest tunnels under construction and to gain any information that might bo available as to the latest and most improved methods of boring. , Thus 1 visited the great Lavctzburg tunnel, which is being bored through the Swiss Alps below Berne. This is eight miles long, nearly throe miles longer than the one 1 am going to make through the Arthur Pass. 1 spent some little time there and saw a great deal that was of much interest and value to me. Especially I found that good progress was being made with the air-drill which was worked by means of compressors driven by electric motors. They obtained their driving power from the great: power station of the Swiss Government at Gampel. It is not farabout 12 milesfrom Brigue, or in the German spelling ' Brieg.' In my work, of course, I can get abundant electric power with the aid of the numerous streams and waterfalls that are to be found among the New Zealand mountains near at hand. Next 1 inspected another long tunnel /at Goppelsternj-near the mouth of the Snn--1 plon tunnel, on the. main shortened lino through from France to Italy. Then 1 visited various other tunnels and works successively in Northern Italy and in Austria, including the Taueru tunnel in the latter country, which is six miles long. I found that in this one the contractor had just completed the 'heading.' He had worked with a plant erected by a Winterthur firm..! It included hydraulic Brandt drills. The engineers treated me with the greatest kindness and courtesy and afforded me every possible opportunity of seeing tiie drills at work and everything else that could lie of any use or interest to me. "Next," continued Mr. McLean, "I returned to London ami visited various works, proceeding then to view the water supply works in South Wales and in the Derwent Valley. After carefully studying all (he different methods in actual operation, I came to the conclusion that the air percussion drill was the, best one for my work—that is to say, for boring lie hard slaty rock through which most of the Arthur's Pass tunnel will have to penetrate. Having convinced myself that this was best, I lost no time in acting upon that, conviction. I immediately let a contract with the Ingersoll Band Company, of New York, for the supply of the machinery of this class which 1 required, and these contractors wore so expeditious in carrying out their contract that all this machinery has not only been already delivered to me, but is actually now on its way to New Zealand, where it should arrive before the end of next month. lam getting the other machinery in England. Messrs. J. B. Hall and Co., of ' Oldham, Lancashire, are supplying mo with the dynamos and motors for driving my drills. I am in negotiation with other English firms for the supply of the Pel ton wheels, cranes, locomotives, wheels, rails, etc., which I. shall require. The Pell on wheel is, as 1 daresay you know, worked by the projection of a powerful jet of water against the numerous small buckets which stud its periphery; it is the must convenient mode of utilising water power. 1 have decided to employ the air-drill in preference to the hydraulic oik; because on the whole 1 consider it the best. The. sole practical drawback is the constant fine, dust, it produces in piercing the rock, hut, I find that that can be effectively got. over by means of a water-spray'." "How long do you expect the work to occupy?" he was asked. "That is more than I should like to predict," said Mr. -McLean, laughing. "So many difficulties may arise unexpectedly in this sort of work and in such a big contract. But at; present I do not see a prospect of anything more formidable than I have made duo allowance for, and at any rate I fully contemplate that I shall be able to complete S.UBM'JOIV: put! UOSJOTtI.I V:.ISSOJ\: jo 31118010 the tunnel within my contract time— years." _________________