Engineering Wonders of the World
Volume I

THE WHITE PASS AND YUKON RAILWAY. 33 the Summit, a distance of 16 miles. Beyond the Summit the gradients are much easier and comparatively short, the maximum being 2’91 per cent, and the average ’84 per cent, against south-bound traffic. The more important bridges are of steel, of varying styles of construction to suit the local conditions. The largest is a Bridges. steel cantilever bridge across a deep canyon near the Sum- mit. This bridge is 835’9 feet long, and the track is 267 feet above the bottom of the canyon. The minor bridges are of wooden trestle construction with 12" x 12" posts, and spans between trestles of 15| feet. The alignment is based on a maximum curve of 16°—that is, a radius of 359’3 feet. There are forty-four such curves between Skaguay and the Summit, and twelve between the Summit and Bennett. The Alignment, total deflection or curvature be- tween Skaguay and the Summit is 4,392°, equalling 12’2 circles in the 20 miles. Between the Sum- mit and Bennett the correspond- ing figures are total deflection 2,689°, equalling 7| circles. The longest straight length between Skaguay and the Summit is 2,831 feet in the fourth mile, and the longest curve is 1,095 feet in the fifteenth mile. The outer rail on curves is elevated for a speed of 15 miles an hour between Skaguay and the Summit, and of 25 miles an hour between the Summit and Bennett. Beyond Bennett the engineering presents no special features. The elevation of the track above sea-level at the Sum- mit of the White Pass is 2,865 feet, and at the Summit at (1,408) Log Cabin 2,916 feet, and at Lake Bennett 2,158 feet. A telegraph, and also a telephone line are used in connection with the railway working, and these are also available for public service. The line is worked continuously throughout the year, though the winter storms on the White Pass sometimes last for weeks with tem- peratures far below zero. Snowdrifts as high as 35 feet have at times to be cleared away for considerable distances, and the normal depth of the drifts dealt with daily by the rotary snow-ploughs in keeping the track clear averages from 3 to 5 feet. Note. — The photographs illustrating this article were kindly supplied by the White Pass and Yukon Railway Company. A ROTARY SNOW-PLOUGH AT WORK. 3