IM-TTON. 



THE JURASSIC — THE COLOB. 77 



lations arc quite the same. But as we pass eastward into the, great 

 amphitheater of the Paria Valley they at length take the form of cliffs 

 of very striking aspect The numerous ledges rise in quick succession, 

 step by step from the valley bottom to the base of the Eocene mass of 

 Table Cliff, which stands as a glorious Parthenon upon the summit of a 

 vast Acropolis. The many superposed cliffs which constitute this stair- 

 way are severally of moderate dimensions, but their cumulative altitude 

 is more than 4,000 feet, tier above tier, and their composite or multiple 

 effect, intensified by the exceeding sharpness of the infinite details of 

 repetitive sculpture, places it among the grander spectacles of the 

 Plateau country. In their coloring, these cliff's are quite peculiar. There 

 arc no red, purple, orange, and chocolate hues, such as prevail in other 

 formations, but pale yellow and light brown in the sandstones and blue- 

 gray to dark iron-gray in the heavy belts of shale. The tones are very 

 light and brilliant on the whole, the darker belts playing the part of a 

 foil which augments rather than diminishes their luminosity. 



THE JURASSIC. 



Beyond the Cretaceous, as we descend the stairway of terraces, the 

 Jurassic comes to daylight. It forms a belt encircling the Cretaceous 

 and outside of the latter. It is composed of two groups of strata ; the 

 upper consisting of red sandy shales with belts of impure limestone; 

 the lower a great mass of white sandstone, nearly a thousand feet thick. 

 The red shales contain abundant fossils, strongly characteristic of their 

 Jurassic age, while the sandstone below is wholly barren of organic re- 

 mains. The sandstone, however, is full of interest on account of its 

 remarkable lithological characters. From summit to base, it is appa- 

 rently one indivisible stratum. Here and there signs of a division are 

 suspected, but closer scrutiny shows that they are produced by the con- 

 tact of one plexus of cross-bedding with another, or by some other cause 

 not affecting the dominant fact. It is remarkably homogeneous through- 

 out its whole mass. On a near view of the rock faces thev are seen to 

 be covered with a wonderful filagree of cross-bedding. On every cliff 

 and headland, on every butte or rocky knoll where this huge stratum is 

 exposed, the rock faces are etched with an arabesque as beautiful as 

 frostwork. Along hundreds of miles of linear extent, and over thou- 

 sands of square miles of surface of the country, this graceful waving of 

 myriads of curves is displayed. Cross-bedding is common enough in 

 other regions and other formations, but nowhere in the world, I fancy, 

 can such a profusion of it be seen. 



The Jurassic sandstone is also conspicuous for its cliffs. Here every 

 formation has its own style of architecture and sculpture, which are as 

 distinctive as the lithological constitution, for upon that constitution 



