/ 
202 F. V. Hayden on the Lignite deposits of the West. 
of 4 feet or more, almost entitely composed of them, The spe- 
cies seems to be identical with the one found in a similar geo- 
logical position in the lower lignite beds of the Upper Missouri 
near Fort Clark, and at the mouth of the Judith river, and 
doubtless was an inhabitant of the brackish waters which must 
have existed about the dawn of the Tertiary period in the 
west. No other shells were found in connection with these in 
Colorado, but on the Upper Missouri well known fresh-water 
along the eastern base of the mountains, and from the best in- 
formation I can secure, I have estimated the area occupied by 
them north of the Arkansas river at 5,000 square miles. Ac- 
cording to the explorations of Dr. John L. LeConte during the 
past season, which are of great interest, these same lignite for- 
mations extend far southward into New Mexico on both sides 
of the Rocky Mountains. Specimens of lignite brought from 
the Raton mountains by Dr. LeConte, resemble very closely m 
appearance and color the anthracites of Pennsylvania. It 18 
probable that no-true coal will ever be found west of longitude 
- 96°, and it becomes therefore a most important question to as- 
certain the real value of these vast deposits of lignite for fuel 
and other economical purposes. Can these lignites be employ 
for generating steam and smelting ores? In regard to the lig- 
nites in the Laramie plains, I have as yet seen no analysis, but 
ee P M 
Bolder creek were submitted to Dr. Torrey by the U. P. B. B. 
Co. for examination, with the following result 
Water in a state of combination, or its elements, - - - - - 12°00 
Volatile matter expelled at a red heat, forming inflam- 
e gases and vapors, -______ _ ae 
Fixed carbon, 2... 52525542 Ae 59°20 
Ash ofa reddish color, sometimes gray,.......-.-.-- 2°80 
100°00° 
A specimen from Coal creek, 3 miles south, yielded similar 
results, . 
Water in a state of combination, or probably its elements 
as in dry wood,__.______. 20-00 
* see ; 
Volatile matter expelled at a red heat in the form of in- 
ammable gases and vapors, 19°50 
Fixed carbo ese 
Ash consisting chiefly of oxyd of iron, alumina, and a 
fittie tlie, ff at gos ae 9-00 
—— 
-  100°00 
