GAJTKETT.] GEOGEAPHICAL WORK. 457 



a defensible position, corraled our stock at night, and took other pre- 

 cautions customary under similar circumstances. As usual, definite 

 Information diminished the danger very much, and after two or three 

 days' delay we went on. Crossing to the Yellowstone by Howard's 

 road, we stopped two days at the Falls, then drove on down the river, 

 and reached the Mammoth Springs, where our supplies were stored, on 

 September 7. From that date to the 12th we were busied about that 

 place, visiting, among other points, Sepulchre Mountain and Electric 

 Peak. 



On the 12th we started again, returning up the Yellowstone to Bar- 

 onette's bridge, where we crossed it, and followed up the East Fork to 

 a point above the mouth of Soda Butte Creek. Then leaving it, we 

 crossed to Pelican Creek, by which and Turbid Creek we reached Yel- 

 lowstone Lake. Then we followed the lake up to the head, and went 

 several miles up the Upper Yellowstone. Eeturning, we followed the 

 lake shore around to the head of the river, and thence followed the river 

 trail down to the Mammoth Springs, reaching them on October 2. 



Having refitted, we started again, this time up the ISTorris road, to 

 survey the drainage areas of Gardiner's and Gibbon Rivers. We trav- 

 eled up the wagon road nearly to the head of the canon of the Gibbon, 

 which enabled me to connect with the work done in that neighborhood 

 earlier in the season. Then we skirted the east base of the Gallatin 

 Eange, making stations on the summits; and then, the season being 

 far advanced, the weather being very bad, and the snow rapidly becom- 

 ing deeper, I judged it best to close the work, although the whole plan 

 had not been carried out. 



We arrived finally at the Mammoth Springs on October 11, and at 

 Bozeman, where the party disbanded, on the 16th. The whole distance 

 traveled by my party is esti-mated at 830 miles. In the prosecution of 

 my w^ork I traveled an estimated distance of 1,250 miles. 



GEOGRAPHICAI. WORK. 



The area assigned to me for survey during the field season of 1878 

 was the Yellowstone i^ational Park, situated mainly in northwestern 

 Wyoming, though embracing narrow strips of Idaho and Montana. 

 The area is 3,312 square miles. 



While a part of this region had been surveyed by the meander 

 method, in 1871 and 1872, by this organization, still there were large 

 gai)s in the maps; while, in addition, the whole work required correc- 

 tion by the introduction of a system of triangulation. Many recou- 

 noissances of the Park have been made, the War Department having 

 sent no less than four distinct expeditions (of which more hereafter), 

 but all have traversed very nearly the same routes, so that the map of 

 any one of them is very like those of the others, difi['ering only in mat- 

 ters of detail or of longitude. For this reason I have used only the 

 earlier maps of this organization, in so far as I have used any other 

 work than my own, in making up the general map ; as I had found, 

 experimentally, that the work of Schonborn and of Bechler was at least 

 as good as any other which had been done in the region, and covered 

 all the country which any of the others do. 



Within the Park Mr. Wilson located three primary points — Electric 

 Peak and Mounts Washburn and Sheridan. Starting from these, I 

 established a large number of secondnry points, distributed over the 

 Park to as good advantage as the topographiciil conditions would ad- 



