Engineering Wonders of the World
Volume III

136 ENGINEERING WONDERS OF THE WORLD. UNION PACIFIC TRACK WEST OF LAWRENCE STATION. Progress of the Central Pacific. pushed ahead, the Central Pacific also pro- gressed rapidly. Starting from Sacramento, about 140 miles from San Francisco, it commences at once to climb the Sierra Ne- vada, and in 105 miles attains an elevation of over 7,000 feet at Summit, without any undulations of the track, and by a constant rise from the foot-hills to that point. A peculiarity of the route is the fact that the engineers have taken advantage of a bold ridge which runs out from the main chain of moun- tains, and reaches nearly to Sacramento, just as the ridge at Sherman Pass on the Union Pacific runs from the Rockies down to the plains. By following this ridge all the way up to the sources of the South Yuba, an ex- cellent natural grade was obtained, broken by but few ravines, and having a uniform and continuous ascent. Such another path across the mountains is not to be found for hundreds of miles up or down the range, and, in all of the passes used by wagons the mountain side is too precipitous to be suit- able for railway purposes. From the valley of the South Yuba across to the Truckee River, the deep snow belt, thirty-five miles broad, is met. For the greater part of this distance the road follows a side-hill „ . .. . . . , , Snow Belt, line, which tor the most part is so sheltered as to be available for winter traffic. Here the snow-sheds are located, and between them are embankments and tunnels,