244 
Prof . Hayden’s Explorations . 
[April, 
River comes from a high plateau in a zigzag course, flowing 
sometimes with the strike, and sometimes with the dip of 
the strata. Its general course on the western line is about 
north-west, from which it turns to the northward and west- 
ward, finally changing to north-west again, to its junction 
with the Grand. It is in canon the greater part of its 
course. 
In the region of country north of Grand River the geolo- 
gical formations extend uninterruptedly from the Red Beds 
exposed on Grand River to the white tertiary cliffs forming 
the summit of the “ Roan Mountains,” or Book Cliffs. The 
Grand is generally in a canon in the Red Beds ; on the 
north side the No. i 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 por- 
tion. The cliffs are composed mainly of cretaceous beds, 
rising one above another in steps until an elevation of about 
8000 feet is reached. The summit is the edge of a plateau 
sloping to N.N.E. 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 their seams, 
and of little economic importance. 
The White River division was directed by G. B. Chitten- 
den, as topographer, accompanied by F. M. Endlich, as 
geologist. 
The district assigned to this party as their field for ex- 
ploration during the season of 1876 commenced from the 
eastward at longitude 107° 30', joining on to the work pre- 
viously done, and extended westward 30 miles into Utah 
Territory. Its southern boundary was N. latitude 39 0 38', 
while the White River formed the northern limit. In order 
to complete to the greatest possible advantage in the short 
time that could be allowed, it was determined to make the 
White River Agency head-quarters, and in two trips from 
there complete the work. About 3800 square miles com- 
prised the area surveyed. 
In working up the topography of this district the party 
spent forty-eight days of absolute field-work, made forty-one 
main topographical stations and sixteen auxiliary ones, and 
travelled within the district about 1000 miles. The party 
ascertained the courses of all the main trails, the location 
