Engineering Wonders of the World
Volume I

280 ENGINEERING WONDERS OF THE WORLD. range. Here Stony Creek Bridge. eight miles east of the summit of the Selkirk the railroad, at an altitude of 3,673 feet, crossed several narrow gorges carved out by foaming rivers. The greatest of all these bridges is that across Stony Creek, a leaping torrent of water flow- ing at the bottom of a narrow cleft in the rock 300 feet below the surface of the road. in position, holes for the rods bored, and the nuts screwed tight to make all safe. For the men who did the work it was an unpleasant business, walking on a slippery stringer, balan- cing on an ice-covered plate, or perched on a truss 30 or 40 feet above the ice. Those who have experienced the nervous thrill attending recovery from a foot-slip under such condi- tions remember also no doubt the bite of the PILE-DRIVING THROUGH THE ICE FOR BRIDGE CONSTRUCTION. icy wind as they slowly bored an auger holo through eleven or twelve inches of frozen fir, and presently hung over the same beam, directing with both hands the end of a long quivering truss rod. The great feature of the Rogers Pass is the long line of snow-sheds—solid structures of cribwork and piling, filled in with stones, and placed wherever a snow-slide appears on the mountain side. Snow- * , > sheds. It built continuously, they would stretch for nearly six miles. They are The original structure was at the time the premier timber railway bridge in the world, being 296 feet high by 450 feet long. It was a continuous Howe truss of four spans, 161, 172, 86, and 33 feet respectively, supported by wooden towers 200 feet high on concrete footings. The present structure, erected in 1893, is a steel arch truss, with a span of 33G feet and a rise from the abutment of 120 feet. The frosts of winter were at once a great help and a serious hindrance to the work of rivers and ravines—a help be- cause the solid ice which covered the water made the task of pile-driving and erect- ing the superstructure much simpler and quicker. Holes were cut in the ice for the piles, which were drawn from the surrounding or close-by woods, and quickly driven in solidly. Light “ false work ” (temporary scaffolding) was then erected upon the ice to support the sills of the bridge floor until the truss beams could be placed the Cold and Dangerous Work. DIAGRAMS SHOWING PLAN OF V-SHAPED CRIB TO DEFLECT SNOW FROM AN OPENING IN A SNOW- SHED (top), AND A SNOW-SHED IN SECTION (bottom).