GEOLOGICAL REMARKS. 243 



The rugged mountain chain forming the western boundary of the val- 

 ley, afforded numerous black-tailed deer and sheep. The skins of these 

 animals being much larger than those of the common deer and antelope, I 

 was induced to scour the vicinity, occasionally, in pursuit of them. 



One day, having gone to a considerable distance on this errand, I was 

 passing along upon the crest of a sharp peak, of great height and steep 

 sides. 



The ridge ranged from northwest to southeast, leaving upon its right 

 side a vast spread of smooth snow, encrusting it from summit to base, and 

 upon its left, a lateral vallon, entirely bare and graced with frequent spots 

 of grass, as yet green and flourishing. 



One of these niches was occupied by a band of wild sheep, which were 

 so situated they could not be successfully approached, unless from the op- 

 posite side of the peak. Attempting this, I w^as proceeding slowly along, 

 by means of steps implanted in the thick crust with the breech of my 

 rifle, and had almost attained the point designed, when, losing foot-hold^ I 

 fell prostrate, and, after gliding the distance of a full mile, almost with the 

 speed of thought, found myself immersed in a huge bank of loose snow, at 

 the foot of the mountain. 



It is all nonsense to talk of steam-boats and rail-road cars, in comparison 

 with the velocity of such a lofty specimen of " gettin down stairs !" Few 

 mortals, I may venture to say, ever got along in the world half so fast as 

 did myself in this grand avalanche from the mountain-top. 



The country contiguous to this valley is generally possessed of a very 

 good soil, both in the prairies, table lands, and mountains. Bordering upon 

 the watercourses, the surface discloses a deep mould of sand and gravel, 

 exceedingly fertile, reposed upon a substratum of granite and micaceous 

 sandstone ; the prairies presented a mixed superfice of sand, clay, and 

 gravel, rather thin and light, and strongly impregnated with various salts, 

 — and the table lands, a compound of stiff clay, stone, and gravel, partially 

 enriched by the fertilizing properties of vegetable and animal matter and 

 the genial auxiliaries of disintegrated rock, with now and then a diminu- 

 tive spot destitute of grass or herb and whitened by a thin coating of sa- 

 line efflorescence. 



The prevailing rock is sandstone, granite, gneiss, limestone, and large 

 boulders of the primitive formation. 



The only indication of minerals, so far as my observation extended, was 

 that of iron, though doubtless due research would bring to light a rich sup 

 ply of other valuabls ores. 



21* 



