GEOLOGICAL SUEVEY OF THE TEEEITOEIES. 155 



ward we might take a glance at Bear Lake Valley, which is destined 

 to be a point of great interest, not only to tourists from the grandeur 

 of the scenery and the beauty of the lake from which it takes its name, 

 but also to settlers on account of the fertility of its soil. This lake is 

 an expansion of a branch of Bear Biver, and is about fifteen miles long 

 and four or five in width, and well stocked with trout. About thirty 

 miles to the north are the far-famed soda springs of Idaho, which will 

 repay the time spent in visiting them. 



Taking the cars again at Evanston we shall soon find ourselves at the 

 divide between Bear Biver and Echo Canon at an elevation of about 

 seven thousand feet above tide-water. The country we have passed 

 over presents nothing new or striking ; the same reddish clays and sands 

 which we have seen before, seem to have been woru down into a fine 

 rolling surface, which is covered with a good growth of grass, giving 

 the whole scene a cheerful aspect. Game, as antelope, elk, deer, bear, 

 &c, was formerly abundant all over this region, and the experienced 

 wary hunter might discover some even at this time; but all along the 

 line of the railroad game of all kinds is fast disappearing. 



The tunnel at the head of Echo Canon is cut through the reddish and 

 purplish indurated sands and clays of what I have called the Wasatch 

 Group, of miocene tertiary age. It is seven hundred and seventy feet in 

 length, and is the longest tunnel on the Union Pacific road. After pass- 

 ing through it, the trains move slowly over the piers of trestle-work, 

 which creak and tremble beneath their load. One section is two hun- 

 dred and thirty feet long and thirty feet high, the other four hundred 

 and fifty feet in length and seventy-five feet high. We then enter one 

 of the narrow grassy valleys which leads soon into Echo Canon, and 

 then we sweep rapidly down between lofty conglomerate walls on either 

 side, which have been weathered into the most fantastic forms. 



Indeed, this entire valley is, for the most part, one of erosion. The 

 water in past geological times has carved out of the massive conglom- 

 erates its deep channel, and on either side the rocks rise wall-like five 

 hundred to one thousand feet. Some portion of the lower part of the 

 valley passes through a monoclinal rift; that is, the beds incline to the 

 northwest, so that on our right as we descend we see the projecting 

 edges. All these beds seem to have a greater or less dip to the north- 

 west, apparently from the Uinta range. 



At the head of Echo Canon the first objects that attract our attention 

 are the massive reddish sandstones on our right, five hundred to eight 

 hundred feet high, which have weathered into curiously castellated 

 forms, and to which the general name of Castle Bock is given. As we 

 pass down through some of the wildest scenery in the world, our eye 

 will be constantly arrested by some unique shape into which these 

 variegated sandstones and conglomerates have been worn by time. 

 Witches' Bock, Eagle Bock, Hanging Bock, Conglomerate Peaks, Sen- 

 tinel Bock, Monument Bock, all greet us in turn as important land- 

 marks. 



The Conglomerate Peaks of Echo present a near view of these con- 

 glomerates, so that even the depressions in the smoothly- worn surfaces 

 of the boulders can be distinctly seen. A little side stream has worn a 

 deep gorge, and scattered vast piles of debris below. The different 

 sizes of the pebbles are also well shown; its walls are about five hundred 

 feet high. 



Monument Bock is one of the most remarkable landmarks in this 

 valley. It is a regular obelisk of conglomerate, standing at the junction 

 of the Echo with the Weber Valley, nearly one thousand miles west of 



