74 APPENDIX TO THE EEPORT OF THE SECEETARY. 



Starting a second time from tlie spring's, the party traveled south- 

 ward to tlie headwaters of Gardiner's Eiver and Gibbon's Fork of the 

 Fire Hole, following the road recently cut by Colonel Norris, superin- 

 tendent of the Yellowstone National Park, from the Mammoth Springs 

 to the Geyser Basins. Having completed their work in this direction, 

 they spent a few days in studying the south end of the Gallatin Eange, 

 which separates the waters of the Yellowstone from those of the Gal- 

 latin, and then returned to the Mammoth Spr>ngs; whence, having been 

 joined by Messrs. Peale and Mushbach, they went to Bozeman, Mont., 

 where the party disbanded. 



The above is a sketch of the route of travel of the party. From it 

 the geologist and topographer branched off widely, thus covering the 

 country between the routes of travel. 



The area embraced in this survey is about 3,500 square miles, of which 

 material for a map on a scale of one mile to an inch was secured. In 

 prosecution of the work of secondary triangulation and topograi>hy 47 

 stations were made, from which 2,100 horizontal and 500 vertical angles 

 were measured. Altogether 370 points were located, an average of 1 in 

 9| square miles ; 230 observations for height were made with the mer- 

 curial barometer, and 100 with the aneroid. 



Material for maps in detail of all localities of special interest was col- 

 lected. Among these may be mentioned the well-known Geyser Basins, 

 on the Fire Hole, the Shoshone Geyser Basin, the fine group of springs 

 at Heart Lake, and those on Gibbon's Fork discovered by Colonel N or- 

 ris, the Mammoth Si)riugs on Gardiner's Kiver, the Mud Geysers on tlie 

 Y^ellowstone, and others. The heights of all important waterfalls were 

 determined by measurement with the tape-line, and thus the vexed ques- 

 tion of the height of the Yellowstone Lower Falls was definitely settled. 



The area occupied by the Yellowstone Park has a great elevation, 

 ranging in the flat country from 0,500 feet to 9,000, while its mountain 

 peaks reach heights of 11,000 feet. Its mean elevation is about 8,000 

 feet. Within this elevated region head three large rivers, the IMadison 

 and Yellowstone, which flow ofl" northward to join the Missouri, and the 

 Snake, or Lewis Fork of the Columbia, which at first has a southerly 

 course. The greater part of the Park is a rolling jflateau, broken here 

 and there by small groups of mountains, as the Bed Mountains and the 

 "VYashburu Group. East of the Yellowstone Eiver, separating its drain- 

 age from that of the Big Horn, is a high, rugged, volcanic range, whose 

 peaks reach 11,000 to 12,000 feet. This range was, in 1871, named 

 "Yellowstone Eange" by Dr. Hayden. 



Excepting a narrow belt in the northern i^art, this park is everywhere 

 heavily timbered. Indeed, with the exception of Washington Territory 

 and the western i)ortion of Oregon, it is the most densely timbered area 

 in the West. There is practically no arable land within its limits owing 

 to its great altitude, and, except along its northern border, little open 

 country suitable for pasturage. 



