2 Geology, &c. of the country west of the Rocky Mountains. 
the first buffaloes ; in fact no animals deserving of notice had been seen 
before, for all appear to have been destroyed by the hunters, or to 
have fled from their pursuit. From this time buffalo meat was the 
principal, or rather only article of food, and much of the time it was 
eaten even without salt. Still from that cause little inconvenience 
was experienced. 
Do carnivorous animals seek licks and salt springs, or herbivo- 
rous animals only, and would man live on vegetable food without 
that condiment, and not suffer in his health ? ‘Tt was now the first 
of June, and to this time there had been frequent rains, thunder 
showers coming from the N. E. and the thermometer ranging at 
noon from 50° to 80°. 
Now crossing the South to the North branch of the Platte, our 
journey was continued up the south side of that river in a W. 
direction about three hundred miles, over a country, for the first two 
hundred miles, similar, in most respects, to that on the main river 
below. The river was shallow, rapid and muddy ; it was about one 
mile wide with extensive bottoms on one or both sides, which were 
in many places, incrusted with salt, a mixture of muriate and sulphate 
of soda; prickly pears, (cactus) and a kind of shrub, called wild 
sage, were found very extensively over the prairies. The bluffs in 
our rear were of sandstone, often worn into the form of domes and 
columns, and the country back afforded so little water that the river 
rather increased than diminished in size, as we ascended towards the 
mountains. Thermometer from 75° to 80° at noon. For days, 
hardly a tree was to be seen, even along the river, but on the Black 
Hills, which we now reached, stretching at right angles to the course 
of the river across the country, a few stinted cedars were observed, 
from the dark appearance of which, probably proceeds the name of 
these heights. Here the country, for two or three days travelling be- 
comes quite broken, affording refreshing streams and green herbage. 
The rock is gray puddingstone, and red sandstone in strata, rising 
a little towards the west. ‘Then the country becomes open on the 
north of the river, but mountains appear on the south, and probably 
continue on in that direction, till they join the Rocky Mountains 
at the place where they were seen by Major Long. Snow was 
seen in the higher parts of these mountains, at this time, being the 
middle of June. 
The river tending S. W. we soon crossed it, and continued our 
journey about west, most of the time along a branch of the Platte, 
