Engineering Wonders of the World
Volume III

FIRST AMERICAN TRANS-CONTINENTAL RAILROAD. 143 TELESCOPIC SNOWSHED, SHOWING MOVABLE LENGTH PUSHED BACK INTO LARGER SECTION. This arrangement makes it possible to isolate a snowshed fire, and in summer to give travellers a better view of the scenery. So the reconstructing engineers decided to build a straight cut-off from Ogden across the two northern arms of the lake and the promontory which separates The Lucin to Strong’s Knob on the west shore, and thence to Lucin over an easy grade. The total length of the cut-off is 102’5 miles, a saving of 43’5 miles over the old route. The new line has a maximum grade of 21 feet to the mile. From the promontory to Strong’s Knob it is level and almost straight. The fall from Ogden to the east shore is 100 feet, and the rise from Strong’s Knob to Lucin only 200 feet in 52 miles. Both of these allow of very easy grades, the country being quite level. There are two slight curves, but the whole section from the promontory to the Knob is only 263 feet longer than the air-line distance. A Great Feat of Engineering. The distance The line is practically free from those engi- neering obstacles which are generally found in a mountainous region ; yet it presents something new to the engineering world—a feat found in the execution to be full of difficulties and surprises. from shore to shore is about 22 miles, all of which is trestle and embankment in the lake except the short stretch of cutting across the promontory. The distance between the east shore and the promontory is, roughly, 8| miles, and over part of this the water has receded, leaving a bed of mud which was in many places from 8 to 10 feet thick under the salt crust. Great variations in the consistency of the lake bottom were encountered during the driving of the piles for the trestles. At times a blow of the “ monkey ” did not sink the pile more than an inch or two ; at others a