94 
IOWA ACADEMY OP SCIENCES. 
could then see the whole of North Park, and much country in 
every direction, probably, in all, 4,000 square miles. 
It is worth a trip to Colorado to stand on the top of Rabbit 
Ear. In North Park we had found scoriaceous rock, which 
called to mind forcibly the thought that a volcano was not far 
away. In ascending Rabbit Ear it soon became apparent we 
were on the very cone itself. Along the sides, in great pro- 
fusion, were fragments of scoria, with occasional slag- like 
masses. These continued to the top, where the two great ears 
seemed to be firmer, more like trap, though not entirely 
uniform, some portions weathering away much faster than 
others. We had no means of determining our altitude at this 
point, but from the snow about us (this was July 12th,) and the ) 
Alpine vegetation, it must have been about 12,000 feet. 
Steamboat Springs is northwest of Rabbit Ear about eighteen 
miles. The pass here, at this time, was completely dry, but a 
little earlier it is very muddy, almost impassable. On reach- 
ing the western edge of the Park range, about seven miles 
east of the Springs, it seemed as if we had come to a jumping- 
off place. Par below us we could see the Bear with its beauti- 
ful valley, green fields of oats and timothy, the little log 
houses of the pioneers, and to the right in the distance, nestled ^ 
at the foot of this great mountain range, lay the village. 
Steamboat Springs. The Yampa or Bear river here runs west 
from Egerla Park, but at the Springs it turns south. 
The mountains to the south of the Bear appear to be much 
lower, and differ in many respects from the Park range just to 
the north There is not that boldness, that ruggedness, 
although separated only by the narrow valley of the Bear. 
The student of geology could not fail to be impressed with this 
difference, as he stands at this point on the southern edge of 
the Park range. On descending the mountain but few 
extensive rock exposures are seen. Most, if not all, of the 
rocks show metamorphism, being derived from what seems to 
have been some kind of sandstone or argillaceous shales. No 
marble was noticed in this locality. On the north side of the 
Bear river, in the valley three or four miles east of the 
Springs the region is thickly covered with well rounded 
granitoid bowlders, some of which are ten to twenty feet 
through. These have come from the mountains close by on 
the north. The bed and banks of Pish creek are a mass of 
bowlders, with very little filling between them. This is a 
