1877. ] Explorations in Colorado. 79 
On the north side, the number one Cretaceous sandstone forms 
a hog-back sloping towards the cliffs. Between the crest of this 
hog-back and the cliffs, there is a broad valley formed by the 
erosion of the soft Cretaceous shales which extend to the base of 
the cliffs and in some places form their lower portion. 
The cliffs are composed mainly of Cretaceous beds, rising one 
above another in steps, until an elevation of about eight 
thousand feet is reached. The summit is the edge of a plateau 
sloping to north-northeast. This plateau is cut by the drainage 
flowing into the White River from the south. These streams 
rarely cut through the Tertiary series. 
Coal of poor quality is found in the sandstones of the Dakota 
Group and also in the sandstones above the middle Cretaceous 
beds. Wherever noticed it was in thin seams and of little eco- 
nomic importance. 
The White River division was directed by G. B. Chittenden 
as topographer, accompanied by Dr. F. M. Endlich as geologist. 
The district assigned to this party as their field for exploration 
during -the season of 1876 commenced from the eastward at 
longitude 107° 30’, joining on to the work previously done, and 
extended westward thirty miles into Utah Territory. Its south- 
ern boundary was north latitude 39° 30’, while the White River 
formed the northern limit. In order to complete the work to 
the greatest possible advantage in the shortest time that could be 
allowed, it was determined to make the White River agency 
the headquarters, and in two trips from there finish the work. 
About thirty-eight thousand square miles comprised the area 
surveyed 
In working up the topography of the district, the party spent 
forty-eight days of absolute field work, made forty-one main to- 
pographical stations and sixteen auxiliary ones, and traveled 
Within the district about one thousand miles. The arty ascer- — 
tained the course of all the main trails, the location and quality 
of all the water, which is scanty throughout, and can map with 
considerable accuracy the topographical forms and all the water- 
courses. The area is almost entirely devoid of topographical 
“ points” and the topographer is obliged to depend to a con- 
siderable degree on those far to the north and south for the 
triangulation. The country has been heretofore almost entirely 
unexplored, and was described by the nearest settlers as a broken 
cañon country, extremely dry. It was marked on the maps as 
a high undulating plateau, with fresh-water lakes and timber. 
