GEOLOGICAL SUEVEY OF THE TERPJTOEIES. 229 



character is especially prominent opposite Salt and Utali Lakes. The 

 western face, though rocky, does not present that jagged, rugose ap- 

 pearance so characteristic of portions of the Eocky Mountains, but is 

 marked by deep and sharp furrows, down which the little streams formed 

 by the melting snow rush with impetuous speed to the valley below. 

 These little rills and mountain brooks, though but small in volume, not 

 combining to form any extensive streams, are perhaps of more value 

 to the pioneer settler than the larger oues. And in our estimate of the 

 irrigable land of this western country, especially if we pass through it 

 in the latter part of summer or in autumn, we are apt to overlook or 

 underestimate their value. I am satisfied that while in some instances 

 I may have overestimated the capacity of large streams, I have paid too 

 little regard to the small ones. My attention was called in a special 

 manner to this subject while camped near Ogden the present season. 

 Our tents were i^itched on the high ground to the northeast of the town, 

 which, to one traveling along one of the usual highways, would appear to 

 be entirely beyond the reach of irrigation, the elevation being, as ap- 

 pears from the observations of Mr. Schonborn, the topographer of the 

 expedition, over 300 feet above the level of the lake, and about 300 feet 

 above Weber Eiver at the railroad depot. Yet even here I noticed 

 around and for some distance above camp several irrigating ditches 

 well filled with water, from one of which we obtained a supply for camp 

 use. I found, upon examination, that these were supplied with water 

 from little streams running down the indentations in the mountain side 

 to the north of us, fed by the patches of melting snow resting among 

 the crevices along the summit. Although within two miles of the base, 

 and the hot sun shining squarely against what appeared to be a bare 

 and naked rocky wall, we could detect no stream flowing dowmit. Not 

 until we had apj)roached to the very base could we discover the sih^ery 

 thread winding its way down among the bowlders and little fringe of 

 bushes that lined its pathway. This stream furnished water sufiicient 

 to irrigate and supply the wants of a moderate sized farm. Multiply 

 this by tens of thousands and we will have some idea of the importance 

 of these minor and annual streams which generally pass unnoticed 

 except by those immediately interested in them. 



Passing to the interior of the basin, whether moving round the north 

 or south end of the lake, we shall find a succession of " long, abrupt, de- 

 tached, parallel ridges extending in a north and south direction." And . 

 this holds true not only on the eastern side, or Salt Lake Basin proper, 

 but also throughout the greater portion of ISTevada. That such is the 

 case in the southeastern part of this State is' expressly stated in the re- 

 port of the expedition under Governor Blasdel to Pahranagat. Baron 

 Eichthoren alludes to the same character of the ranges in the southwest. 

 These ridges are separated by intervening valleys of various width, and 

 even where the valleys expand into broad open plains, as in the central 

 and western part of Utah, their boundary walls retain the same general 

 course. The valley of the Humboldt might, at first sight, appear to 

 form a remarkable exception to this rule, but a closer examination will 

 show this to be a mistake ; for the greater part of its course it is formed 

 by a series of openings through these ridges and across the intervening 

 valleys. That this is true is clearly shown by the direction of the trib- 

 utaries that flow into it. This uniformity in the direction of these minor 

 ranges was noticed by Captain Stansbury, who states that even the 

 northern rim of the basni partakes of the same character. " The north- 

 ern rim of the Great Basin, or the elevated ground which divides it 



