GANNETT.] 



DKAINAGE SYSTEMS. 673 



Eagle River heads oj^posite the head of the Arkansas, in Tennessee 

 Pass, and flows nearly northwest to the Grand River. Its valley con- 

 sists in the upper portion of broad, fertile meado^vs, with good grass, 

 and abuudance of timber in the hills. 



West of the Arkansas and Eagle Rivers is the great Sawatch Range, 

 which terminates on the north in the Mountain of the Holy Cross. 

 The main divide joins it at Tennessee Pass, and thence south follows its 

 crest. The peaks of this range are between 14,000 and 14,500 feet in 

 height. Few points in the range are below 13,000 feet high, and the 

 average elevation of the range is fully 13,500. The orographical charac- 

 ter of these mountains, as well as those of the Park Range and of the 

 main divide on the north end of South Park, is broad and massive. 

 Heavy, bulky mountain -forms abound, while sharp pinnacles and ser- 

 rated ridges are entirely wanting. This range has an average width of 

 fifteen to twenty miles. 



The country west of the Sawatch Range is drained by the Gunnison 

 River and Roaring Fork, a branch of the Grand River. Their valleys 

 are separated by a heavy range, the Elk Mountains, second only to 

 the Sawatch in magnitude and elevation. The direction of the divide 

 between the two drainage-systems is generally east and west, but the 

 range is, in reality, made ujd of a series of ranges parallel to the 

 Sawatch; i. e., having a direction about south 30^" east, and north 30° 

 "west, joined together by saddle-like ridges, this formation giving rise 

 to a number of large branches of each river, all i^arallel, approximately, 

 to one another. This range is composed in great part of stratified 

 rocks, principally sandstones, disturbed in several places by upheavals 

 of granite. These mountains present aspects entirely dffferent from 

 those of the Sawatch Range, both in color, which ranges from a dull red 

 to a dark brown, and in form, which, instead of the heavy, massive, 

 dome-like structure of the Sawatch Range, presents us here with sharj) 

 pinnacles, spires, jagged ridges, &c. 



The valleys of most of the branches of the Gunnison are narrow, 

 though in some places, as on the main Gunnison and on East River, 

 they expand to broad bottoms several miles in width covered with sage 

 and bunch-grass. 



The vegetation in the mountain valleys is of 'almost tropical luxuri- 

 ance, the sandstone and limestone making a deep, rich soil. Pine and 

 spruce trees cover the ridges heavily, while the bottoms are choked by 

 quaking-aspen trees. 



On the north side of the divide the character of the country is very 

 similar to that on the south side ; *. c, a system of parallel ridges, par- 

 allel to the Sawatch Range. This direction of the ridges is, however, 

 changed as we go farther north to a nearly east and west direction in 

 the latitude 39° 15/^ by the large branch of Roaring Fork, known 

 as Frying-Pau Creek, which drains the west face of the northern half 

 of the Sawatch Range. The elevation decreases rapidly toward the 

 north, being at the mouth of Frying-Pan Creek, in latitude 39° 15', 

 only 7,000 feet ; and with this decrease in elevation there comes a great 

 change in the character of the vegetation. 



The range and extent of agricultural pursuits are determined in this 

 country rather by the elevation than by any other agency. 



The following notes concerning the limits in altitude of the growth of 

 different crops were given me by Mr. W. K Byers, of Denver, from his 

 ow^n experience and observation : 



Wheat, barley, oats, potatoes, turnips, peas, and the hardier garden 

 vegetables are safe crops at any elevation under 7,500 feet. Potatoes 

 43 G s 



