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Show ; 168 J?XPLORATION OF Tfl~~ CANONS OF TilE COTJORADO. of this stairway, the OranO'e Q]'ffi . h feet hio-h . 5 . I s, IS more t an one thousand two hundred b 'and the step Itself IS two or three score miles in wid.th Th d step, the Book Cliffs, is two thousand feet h. h , . e secon miles in width. The third or u . . Ig ' or more, and a score of hiO'h p . l . ' ppei step, IS more than two thousand feet o . assmg a ong tins step, for two or thre . . valley of the Uinta· but th' II . e scOie miles, we reach the than the Toom'-'Ylin mu-near~s ;a ey I/S not five or six thousand feet higher r 1 u-weap for th t · · Climb the Orange Cliffs 1 200 £' h. e s airway IS tipped backward. the Book Cliffs and you h ' ' d eet Igh, and go north to the foot of ' ave gra ually desce d d h the Book Cliffs yo . n e ' so t at at tho foot of u aze not more than a hu d d £ Orange Cliffs In like rna th c ' n re eet above the foot of the nner e 100t of the B. Ol'ffi . higher than the foot of the B 1 01'~ Iown I sIS but ~00 feet . . 00 C IuS and the vaJI f h u· quttethreehundredfoeth'O'h ·th 1' eyo t e mtaisnot T 1 b ei an t 10 foot of tho Drow (n · ffi o go by land from tho valley of Whit R' n I s. Tu-weap', you must gradually almo t. e ~~er to the Toom'-pin Wu-near' th £ ' s Imperceptibly climb sou ' or a distance of forty or :lift miles . a.s you pass to the two thousand :five hundred or tb. yl ' until you attam an altitude of Th I ee t lOusand feet ab th en you descend from tl fi. ove , e starting point. S 'II le tst terrace by an b ti continuing to the south . d ' . a rupt step, to a lower. I · d ' you gta ually chmb a()' · . a tltu e of more than a tb d c , oam, unti 1 you attain an ousan wet who . another cliff, and descend b I ' n you arnve at the brink of a rupt y to the top of th I extending your travels in th d' . e owest terrace. Still time, until you roach the b ~ skamfe hirectlOn, you climb gradually for a third rm o t e third li f }'.tr escarpment of the lower terrace d h ne o c Jus, or the edge of the ' an ere you dj;) d step to the plane of the river at th c vSCen by another sudden d b h ' e lOOt of Labyr' th 0 own y t e river, of course yo d c: m anon. In coming alo ng the pIa ne of the river th u o not ascend ' but you pass these ten·aces lation, the middle teJTace 'thr:u~:e~ terrace, through the Canon of Deso- Labyrinth Canon. b ray Canon, and the third through The beds, or series of rocks th . extend under the beds of G a' ~ rough WhiCh Labyrinth Canon is cut 0 an-on of ' Desolation At ray a. non ' and thes e run under the beds of tl ' C . one time the D l . le anon series extended overth e Lab ri h O eso atiOn series and th G c e ray washed away. y nt ailon series, but they have been PLATEAUS AND llOG-BA.OKS. 169 It will be remembered that in the description of the country lying to the north of Red Oauon and Brown's Park, it was explained that ridges were. formed by the unequal progress of erosion through tho upturned edges of the formations lying on the flank of the fold. Thus ridges are seen where the dip of tho rocks is at a high anglooften twenty to forty five degrees; but where the dip is at a low anglo-from one to five degrees-such ridges are not found; tho cut edges of tho formations stand in steep escarpments, or lines of cliffs, while the slope of tho summit of the formation is very gentle, so that when you climb one cliff tho descent is almost imperceptible to the foot of another. (Compare lines of cliffs, seen in Figure 61, with hog-back cliffs, seen in Figure 52.) In passing through tho last three canons, we have observed that the rocks have thus gently dipped to the north, and so, in following tho river to the south, we are constantly running into rocks of lower geological position and greater age. In this way we are able to study successive beds from higher to lower, as we would should we descend a shaft many thousand of feet in depth, as previously explained. Expand a fold like that of the Uinta Mountains,· where the rocks dip from ten to ninety degrees, to a more gentle curve, where the rocks dip at a much smaller angle, so that the inclination is scarcely perceptible to the eye, and can only be determined by an extended leveling and tracing of the strata, and the hog-backs are thrown farther apart. The escarpments of these hog-backs, facing the axis of the fold, are still lines of cliffs; but the slopes on the opposite sides are so gently inclined as not, at once, to be apparent, and the streams heading near the brink of the cliffs, and running down the gentle slope away from this line, excavate their own valleys and canons, and so break up the plane of this slope that its inclination is not at once observed; in fact, it can only be discovered as a generalization from a careful study, and such an inclined plateau, when seen from the side away from the axis of plication, would usually be considered a range of mountains. Yet it has some features ·which readily distinguish it. The peaks are low mountains and hills, bordering the foot of the slope, and tho table lands are beyond and above them, near the crest of the cliffs which face the axis. 22 OOT, |