F’. V. Hayden on the Lignite deposits of the West. 201 
13. Sandstone. 5. Gray and yellowish gray 
12. Drab clay. sandstone. 
11. Lignite. 4, Drab clay, 3 feet. 
10. Drab clay. 3. Lignite, 11 to 13 feet. 
9. Sandstone. 2. Drab clay, 4 feet. 
8. Drab clay. 1, Fine ye lorfich grit indura- 
7. Lignite, 5 feet ted. 
6. Drab ¢ 
Cretaceous beds, 1, 2, 3, 4, &e. 
The thickness of the beds is given when it could be obtain- 
beds 6 to 13 feet inclusive have been broken down from the 
summit of the upheaval just beyond and thus displaced. - The 
inclination of the strata from 1 to 16 inclusive is 8° east, and 
the cleavage of the beds of lignite is vertical and exactly par- 
allel with the dip. From 13 to 29, inclination is 40°, and the 
remainder, 35°. Lignite beds 38 and 42 have not yet been tested 
and very little is known of them. They have been exposed in 
the search for iron ore. The summit of the hills above all 
these beds in the section is covered with a large thickness of 
‘superficial drift material, which undoubtedly conceals many 
other beds which properly belong to the section. Mines have 
been opened on Coal creek, 3 miles south of Marshall’s mines, 
but they have been abandoned for the present. Another has 
been opened about 20 miles south of Cheyenne City, on Pole 
creek, The drift began with an outcropping of about 4 feet 8 
inches in thickness, inclination 12° east. The lignite grows 
better in quality as it is wrought farther into the earth, and 
the bed, by following the dip 200 feet, is found to be 5ft. 4 in. 
thick, and the lignite is sold readily at Cheyenne City for $25 
er ton. The beds are so concealed by a superficial de- 
posit, that it is difficult to obtain a clearly connected section 
of the rocks. A section across the inclined edges of the beds 
eastward from the mountains is as follows: | 
7. Drab clay passing up into areno-calcareous aes com- 
posed of an aggregation of oyster shells, Ostrea 
onalis 
6. Lignite, 5 to 6 feet. 
5. Drab clay, 4to6 © 
4. Reddish rusty sandstone in thin lamin, ----------- 20 
8. Drab arenaceous clay, indurated, ae 
< Massive sandstone 50 
qo cece 
The summit of the hills near this bed of lignite is covered 
With loose oyster shells, and there must have been a thickness” 
