ENGINEERS' PARADISE

Evening Post, Volume CVI, Issue 27, 1 August 1923, Page 9

ENGINEERS' PARADISE

BRIDGES AND TUNNELS

EARLY CANTERBURY'S PLUCK

The following table shows at a glance how Otira tunnel compares in length and altitude with the six railway tunnels of the world that exceed it in. length:—

r??j worl£ s hi Shest tunnels are - ttf* ffe^OT)' which haa an allude ?Pi,-r > I 4 feet ' and t*l6 Trans-Andine (Chili-Argentine) 10,500 feet; each ia between one and two miles long. t;«? g *f New Zealand's ■ configureZTia J, ar.ee.ra''way systems in thY world equal it m proportion of'tunnel, or of bridges. wtll^ the .0&3 iunneI > the "*°w New 7 t T el?, now fa°ta*>d. in the Ne;^ Zealand railway system is aboufc cln»th^ al w a;i^r hins lp* th« WM lch IB over Xi Per cent, of tb* total mileage of the railway sj*! an£ntT«! "^ , bn'dg6S to?ethei' «,wd 54l COl°Pnta«on takes no ac--needed m a country abounding in enlhes and ramfall, in which culvertaaa wimense amount of concrete has beea the OH» f aie™ (Canterbury) asC ent tt t r 3 r^v^^ B« nile peg, m which there are fifteen tun^ Lt iW n« 13 >215 f^t. Here „<> some of the argest tunnels'in New ZtZ land, estimated in feet:— SOUTH ISLAND- Mt Otlra MM I N Lyttelton 'S'SJ* Caveriham (double"line)' 7.'.'. 4J620 Motuplko (Nelson) 443? Mlhiwaka ( nr . Pt. Chalmers") 4)341, NORTH ISLAND— Poro.o-tarao (N.I. Main Trunk) , .._ Karangahake (Paeroa-Waihij 3,m Mataraa (N.I. Main Trunk) 1 W Rlmutaka (Wgu.-Wairarapa) l,m From tKe above figures it will be seen OH» ?■ *h« recent completion of ££ h«M ' c record for lenßth was he d by the first railway tunnel ever dnven m New Zealand, situated oa the first railway constructed in New/ Zealand. It w« long ago a* 1860-? when railway building acience was still young-that the Canferburv^pSdd Council let a contract for the oonsW tion of the Christchurch-Lyttelton rafl 1$ °n -Whi °h- T rk w« Parted ""£ 1862. It is typical of our hilly islands -though not typical , 0 f lowe/CarC! bury m general—that the engineer* should be immediately confronted wife a great tunnel problem presenbed by the hills which capriciously wall <jff the Canterbury Plains from their port. Even to-day a- railway project-including » tunnel like the Lyttelton tunnel, over a mile and a half long, would be consxdered important. What, then, musfj be said of the courage of Canterbury Province m 1862, when, with a popul/ tion of less than 10,000, the Provincial Council began this great undertaki« K which was completed in 1867! Suvelv this is a great example of courage and self-reliance. *

The Lyttelton tunnel was driven tun der the direction of Mr. Edward Bobson, as Provincial Engineer for the Canterbury Provincial Council. Under him served his son, Arthur Dudley Dobson of Arthur's Pass fame. *'

For the above figures as to Innnete and bridges in New Zealand, we are indebted to the Chief Engineer of Railways, Mr. F, W. Mac Lean, M. last, C.E..

Length, i 'implon 12.26 >t. Gothard 9.32 -oetschberg 9,03 "It. Cenls 7,98 "'ken 6.36 Wberg 6.23 s*lfa ...; 5.3f Altitude. 2313 3788 4077 424S 650 4300 243S