Explorations and Surveys for the Pacific Railroad. 79 



From the South Pass, the route follows down Sandy creek, a 

 tributary of Green river, to the crossing of the latter, and thence 

 to Fort Bridger, (elevation 7,254 feet,) on Black's fork, likewise 

 a tributary of Green river. The amount of work on this section 

 would be considerably less than on the preceding. 



From Council Bluffs to Fort Bridger the distance is 942 miles ; 

 from Fort Leavenworth 1,072 miles. 



The route now ascends the divide between the waters of Green 

 river and those of the Great Salt lake, by the valley of Black's 

 fork, or of one of its tributaries, with grades of 69*5 and 40 "3 

 feet per mile. The summit is a broad terrace at the foot of the 

 Uinta mountains, and has an elevation of 8,373 feet. From this 

 point the line descends over the undulating country separating 

 the Uinta and Bear Kiver mountains, crossing the head of Bear 

 river, and, entering the valley of White Clay creek at its head, 

 follows down that stream to its junction with Weber river. 



The Wahsatch mountains now intervene between this plateau 

 country and the Great Salt lake, and the passage through them 

 may be effected by following Weber river, or by ascending to 

 near the sources of the Timpanogos ; and descending that stream 

 — both being affluents, directly or indirectly, of the Great Salt 

 lake — the distances are about the same to their common point 

 on that lake. * * * * 



Entering the valley of Great Salt lake from either the Weber 

 or the Timpanogos canon, there is no obstacle to the construction 

 of a railway passing by the south end of the lake, and crossing 

 the Jordan, Tuilla valley, and Spring or Lone Eock valley, to 

 its west side. 



By the valley of the Timpanogos, the distance from near Fort 

 Bridger to the south end of the Great Salt lake, on the western 

 side of the valley of the Jordan, is 182*55 miles; the greatest 

 grade required, 84 feet to the mile. The amount of work re- 

 quired on this section, excepting that along the canon, will not, 

 in the opinion of Lieutenant Beckwith, be great. 



From the western shore of Great Salt lake to the valley of 

 Humboldt river, the country consists alternately of mountains, 

 in more or less isolated ridges, and of open level plains, rising 

 gradually from the level of the lake on the east, to the base of 

 the Humboldt mountains on the west ; that is, from 4,200 feet 

 to 6,000 feet above the sea. West of the Humboldt mountains 

 the country is of the same character, the plains declining until, 

 at the west shore of Mud lake, usually called the foot of the 

 Sierra Nevada, the elevation is 4,100 feet. 



The mountains in this space of 500 miles, (by the route trav- 

 elled 600 miles,) between the Great Salt lake and the foot of the 

 Sierra Nevada, have a general north and south course. Occa- 

 sionally cross-spurs close in the valleys to the north and south, 



