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Show GENERAL VIEW OE THE SEVIER PLATEAU. 227 have sculptured ridges of erosion which trend that way. If we view the Sevier Plateau from the north, its transverse profile is alone seen, and the tabular summit slightly inclined is conspicuous to the eye. But if we view it from the east or west, its long summit is seen in many places to be somewhat rumpled and even serrated by the ridges of erosion and by the old volcanic remnants viewed endwise. The northern end of the Sevier Plateau is not well defined. A long, gentle ramp, deeply scarred and much wasted by erosion, begins a little south of Salina and ascends southward to the summit. It is best appreciated as we journey up the Sevier Valley from Salina to Richfield. We then observe the whole platform of the country to the east of us gradually gaining in altitude through a distance of 20 miles, until from being a thousand feet above us at Salina it becomes 5,800 feet above us opposite Richfield, and there presents to the west a stupendous battlement of nearly vertical wall above and abrupt spur-like slopes below, thrusting their buttresses beneath the valley plain. For nearly 10 miles this tremendous escarpment is quite massive and unbroken, simple in form and more than a mile in height. Opposite Monroe a large amphitheater has been excavated in the plateau by a plexus of streams, and may be likened to a, huge bowl filled with mountains. From this point southward the plateau wall is notched repeatedly by profound ravines heading far back in the table, until, at a distance of about 32 miles south of Monroe, the plateau is cut completely in twain by the East Fork Canon. From this gap southward 30 miles the southern division of the plateau presents a very few inconspicuous breaks, and terminates in a low wall at a rather lofty and broad transverse valley known as the Pan quitch Hayfield. The eastern front of the table looks down into Grass Valley, but from a much smaller eminence, both because the eastern front is absolutely lower than the western, and because Grass Valley is absolutely higher than Sevier Valley. The descent into Grass Valley along the northern and central parts of the plateau is rather abrupt, frequently precipitous; but along the southern part it is very gradual. The Sevier Plateau is composed chiefly of volcanic sheets of grand dimensions and enormous cumulative thickness, and of immense beds of |