Ten Millions to Save Four Miles 



I.\ the t'anadian Rock\- iMmintaiiis is a 

 giant mass of rork, towL-riin; f>,.S4() 

 feet and known as Mount McDonald. 

 It lies on the route of the Canadian 

 Pacific Railway. Between Mount Mc- 

 Donald on the right and Mount Tupper 

 on the left, the road enters what is known 

 as Rogers Pass. To reach the other side 

 of the Rockies, the trains had to climb 

 two long spiral loojjs. If they were to 

 tunnel through the mountains the rt)ute 

 v,()uld he shortened only about four 

 miles, but the grades would be reduced, 

 with the result that much time would 

 be sa\xxl as well as wear and tear 0:1 

 rolling stock. Besides, the expense and 

 clanger of maintaining and operating 

 four and one-half miles of snowsheds 

 would also be eliminated. Considering 

 lliese factors, as well as the amazing 

 increase in traffic, an increase which 

 involved double-tracking, it was decided 

 to tunnel Mount McDonald. 



Two years were spent by engineers 

 in seeking the most favorable location 

 for a bore. A spot was di.-.covcrcd best 

 suited for an undertaking in ci\il en- 

 [Jneering which coni])ans fa\-()ral)ly 

 \.ith the wonderful tunneling that has 

 been done in the Swiss Alps. 



The Selkirk Tunnel, as it has beca 

 called, is of interest because of the 

 unusual method employed in the boring. 

 la all such work it is im[)ortant that (he 

 excavated mati'rial shall be renioxed with 

 the greatest facility; that the work uiukr 

 way shall not he im[)eded; and thai pro- 

 \ision shall he made for carrying high- 

 jjressure air pipes for the drills, water 

 ])ipes and ventilating suction |)ipes. 

 And so it was decided to dig two tunnels 

 — one of them a "pioneer tunnel," in 

 engineering parlance, ilu- soli- function 

 of which is to provide an outlet for the 

 excaxatetl material. 



If you will stud\' the pictures a |)pea ring 

 on thene.vl pagi', ><ni will see at once how 

 the pioneer tunnel fullils its pur|)ose. 

 .'\t tin- east end llu' |)i(iiie(T tunnel was 

 located fifty feet to the north of the 

 center line of the main tunnel and .it the 

 west end, lifix leet lo the Miiilli of i|. 

 I'irst ol all, an upper center "heading" 

 was dug. In other words, a rather shal- 



low channel was dug along the line of the 

 main tunnel. After this center heading 

 iiad been made, the work of digging out 

 the main tunnel to its full dimensions 

 proceeded. The material excavated was 

 hauled to the pioneer tunnel, which 

 runs parallel with the main tunnel, 

 through cross-cuts, following the course 

 shown by the arrows in the diagram 

 Oil the following page. 



After being con\eycd through the 

 pioneer tunnel, it was carried back again 

 to the main tunnel, but, of course, at a 

 point far removed from the scene of 

 operations. After that, it was hauled 

 out on a trestle o\er standard-gage 

 tracks through the main tunnel and 

 dumped into regular railwa\- cars. The 

 excavation was, of course, all done by 

 steam sho\els of one and a half cubic 

 capacity, which means that at a single 

 scoop, a shovel would dig out about an 

 ordinary wagonload of dirt and rock. 

 The dirt cars were hauled to the mouth 

 of the tunnel by standard-gage com- 

 j>ressed-air locomot i\es. 



The tunnel, which is fi\e miles long, 

 lowers the summit of the line by fi\e 

 hundred and fifty-two feet. Its esti- 

 mated cost is over ten millicn tioUars. 



The tunnel is twenty-nine feet wide 

 and twenty-three feet high and follows 

 a straight line under Mount McDonald, 

 emerging in the Bea\'er Valle>- beNond 

 at a point about one thousand feet 

 below the i)resent railroad route. 



The eastern end is directh- below 

 Hermit, a station just east of Rogers 

 Pass. The highest point reached in the 

 tunnel is three thousand se\en luiniired 

 and ninety-fi\-e feet below the summit of 

 Mount McDonald peak. I'p to the in- 

 tt'rior summit the passage through the 

 tunnel has a grade of one per cent. The 

 (limb for the tunnel is made b\- the rail- 

 road on the most iiortlierK station on 

 its route. 'The tunnel route originalK' 

 disc-o\-ered h\- the engineers was six miles 

 long, hut this was gradually decreased to 

 conform to the five-mile tunnel. The 

 jiass gi-ts its name from Major A. B. 

 Rogers, who penetrated the faslnes.ses 

 of the Si'lkirks in iSfti and discoxcred 

 this opening through the range. 



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