Beyond this amphitheater, the canyon narrowed 

 quickly, keeping still its depth and perpendicular walls, 

 till finally the river wholly filled its bottom, scarce thirty 

 feet in width, and the sky was hidden overhead in places 

 by the projecting cliffs. 



The rock is a superb deep-red Triassic sandstone, 

 capped by a softer gray Jurassic, and it is the sin- 

 gularly homogeneous character of these ancient wind- 

 deposits that gives them such extraordinary massiveness 

 of cliff and dome in wasting to the sea. 



For these are wind deposits, built up by the gales that 

 swept across a desert land ages ago and buried the broad 

 ocean-litoral that bordered it beneath thousands of feet 

 of clean, wind-sifted sand. There is nothing like them 

 elsewhere, in scale or clear-cut exhibition of the force of 

 wind. The gales that built them up must have blown for 

 millions of years across that desert land before the sea 

 engulfed them, as it later did, to be again hove up still 

 later and form a portion of our present continent. 



The ancient litoral on which they lie, laid bare in places 

 by the Virgin Eiver and in these tributary canyons, shows 

 isolated beds of salt and gypsum where once salt marshes 

 lay, sea shells, and over these, in beds of later date, nu- 

 merous remains of trees allied in type to the vanishing 

 Sequoia group now making its last stand along the west- 

 ern slopes of the Sierra Mountains and on the coast of 

 northern California. They are wonderful relics of the 

 past that should be guarded at all cost. 



The Vermilion Cliffs — washed by the Colorado Eiver 

 once, now sunk a mile below and forty-odd away in a new 

 bed — and the red walls of Zion Creek are formed of these 

 wind-blowix sands, impregnated with iron which cements 

 and tinges them; the gray rock above, seen from the 

 canyon, is formed of them also but without the iron. 



Zion Monument now is easy of approach. A short 

 motor ride across the desert, where the morning and 



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