; Rocky Mountains and Oregon. 197 
In the journey of Capt. Frémont south from Fort Vancouver 
into California, the party crossed the Cascade range (or, as it is 
called in that part, the Sierra Nevada) at a height of 9,338 feet, 
and “several peaks in view rose several thousand feet higher. 
Thus within 150 miles of the coast, and 500 from the sum- 
mits of the Rocky Mountains, there is a range of heights even 
exceeding this chain in elevation. This Cascade range extends 
north and south through Oregon into California, and contains 
several lofty voleanic cones, from 10 to 15,000 feet in altitude ; 
two of them, St. Helen’s and Mount Regnier, are stated by Captain 
Frémont to have been in action at the time of his visit; and he 
adds that “on the 23d of the preceding November, St. Helen’s had 
scattered its ashes like a light fall of snow over the Dalles of the 
Columbia.”’ 
On the ascent of the Rocky Mountains, specimens of the rocks 
and several interesting fossils were collected. As observed by 
belongs, extends at least to a height of 5,000 feet above the sea. 
On Smoky Hill river, in latitude 39° and longitude 98°, the rock 
was an impure limestone and abounded in shells of a species of 
Thoceramus. The height of the place was about 1,500 feet above 
the sea. Near Fort St. Vrain in latitude 105°, and at an altitude 
of 5,500 feet, a similar rock was observed, upon which Mr. Hall 
remarks that ‘two fragments of fossils still indicate the cretaceous 
period; but the absence of any perfect specimens must deter a 
positive opinion upon the precise age of the formation; yet one 
specimen from its form, markings and fibrous structure, I have re- 
erred to the genus Inoceramus.” “The whole formation,” as Mr. 
all adds respecting the seven degrees of longitude travelled over 
to the place just mentioned, “is probably, with some variations, 
an extension of that which prevails through Louisiana, Arkansas 
and Missouri.” Beyond St. Vrain’s Fort, the region towards the 
Wind river mountains changes to granitic. Yet sandstones and 
shales prevailed farther north, near Frémont’s pass and beyond, 
With some thin heds of coal, which Mr. Hall suggests may ae. 
belong to the oolitic period. In longitude 111° and latitude ALZ°, 
on Muddy river, the rock was a “ yellowish gray oolitic limestone, 
containing turbo and cerithium,” and not far distant fossil ferns 
were obtained, among which was one species resembling the 
Glossopteris Phillipsii, an oolitic fossil. Mr. Hall remarks, “this 
