802 REMARKS ON SANDSTONE AND 



air throii2;h the water of this 'bason produces a constant and 

 violent agitation similar to boiling. 



When fresh horn the spring, the water has the taste and 

 appearance of tlie common soda water, and is, I believe, as 

 higl'.lv impiegnated with carbonic acid as it could be by the 

 most powerful artiiicial means. It is extremely agreeable 

 to the taste, and when drunk in the quantity of several pints, 

 is followed by no sensible effects exce|)t a very considerable 

 degree of exhilaration, which is immediate. 



The general direction of the first ridge of the Rocky 

 Mountains, from beyond the Platte to the Peak, is from 

 noith to south. A few miles south of the peak, this ridge 

 abruptly terminates, sending out, in a south eastern direction 

 a long range of low secondary hills. Crossing these in a 

 south west direction, we found, that though broken and ele- 

 vated, they consist almost entirely of horizontal sandstone. 

 This rock is of a yellowish white or light grey colour, of an 

 uncommonly slaty structure, and evidently contains a large 

 proportion of clay. Organised remains are to be seen in it, 

 but these are not numerous or conspicuous. It is traversed 

 by narrow upright veins of carbonate of lime, in crystals. It 

 contains horizontal beds of bituminous shale ; and selenite is 

 sparingly scattered over the surface. This formation of ar- 

 gillaceous sandstone extends far to the south and south 

 west ; it also occupies the large amphitheatre or bay which 

 is formed between the main range of the mountains and the 

 projecting spire which contains the high peak. At the ex- 

 tremity of this bay, the sandstone is red and highly inclined, 

 similar to that on the Boiling-spring Fork ; but this appears 

 to dip under the argillaceous sandstone above mentioned. 

 At the place where the red sandstone ridge is divided by the 

 bed of the Aikansaw, are several springs highly impreg- 

 nated Willi nuniate of soda, sulphate of magnesia, and pro- 

 bably several other soluble salts. They also emit carl)onic 

 acid and sulphuretted hydrogen gases. The water of these 

 springs, except one, is nauseous to the taste, and their dis- 



