GEOGRAPHICAL DESCRIPTION OF THE ROCKY MOUNTAINS REGION. 
105 
Snake river, or the south branch of Lewis’ fork of the Columbia, and is also fertile, but its char¬ 
acteristic feature is the great scarcity of timber for any purpose, the willow and wild sage being 
used for fuel along the whole route. The geological formation of this section belongs to the 
tertiary period. The capability of this broad area, however, for grazing, is excellent. It is a 
great resort at present for all Indians in the mountains, the mountains and valleys affording a 
great abundance of game, consisting of elk, bear, deer, and antelope, while the numerous rivers 
and streams abound in fish and beaver. The latter are still caught in large numbers on the head¬ 
waters and tributaries of the Missouri, but are not so anxiously sought after as years back, 
owing to the great depreciation of value in the market east. The whole country is formed of a 
series of beds of mountainous ranges or ridges, with their intervening valleys, all of which are 
well defined and marked, the decomposition and washings of the rocks of the mountains giving 
character to the soil of the valleys, which may be termed, as a general thing, fertile. The 
geological formations along the Jefferson fork and its principal tributaries are limestone and con¬ 
glomerate rock. From the range called the Snake River divide, the whole character of the country 
is completely changed. Here the geological formation is basaltic and volcanic principally. None 
of the numerous streams and rivulets flowing from the mountains along the route we travelled 
emptied into the Snake river, but either sunk into the ground or formed small lakes in the broad 
valley of Snake river. The ground in most places is formed principally of sand; and where 
large beds of basalt are not found, the ground is of a dry, absorbing nature, through which the 
water sinks, at times bursting out again. It was somewhat singular that for sixty miles above 
Fort Hall, along the main stream of Snake river, we did not cross but one tributary, and that 
coming in from the south, while none came in from the north; all of the streams, as before men¬ 
tioned, either forming lakes or sinking into the ground. This section is also noted for the great 
scarcity of timber, and the immense plains of wild sage; which is so abundant, that it merits the 
name of the sage desert of the mountains. It extends for many miles in length and breadth, form¬ 
ing an immense ocean of prairie, whose sameness is only broken by the ‘ Three Buttes’ of the 
valley, which rise like islands in the sea in this broad and barren area. Its whole character 
might be included in the word sterility. From the mountains bounding the Snake River valley 
on the north to Fort Hall, a travelled distance of one hundred and twelve miles, there is but 
one fertile spot of ground that could be converted to any useful purpose, and this is found at 
Cantonment Loring, five miles above Fort Hall. Here the soil is of a grayish-blue clay and 
sand, that might be made use of for agricultural purposes. The grazing here is most excellent. 
To our return route to the Bitter Root valley, which lay to the east of the Bitter Root mountains 
from the Snake river, to the ridge separating the waters of Wisdom river, or the Big Hole fork 
of the Jefferson river, from those of the Hell Gate river, the same general remarks will apply 
as those describing the country from the head of the Bitter Root river to Fort Hall—a series 
of mountain ranges, giving beautiful prairie valleys, through which wind streams from the 
mountain slopes that pour their tribute into the Missouri and its forks. Leaving the ridges 
referred to, you again enter a different and milder region, through which flow tributaries to the 
Clark’s fork of the Columbia. Here the soil is a rich loam, timber is abundant, and climate 
exceedingly mild even during the severest winter. We enteied it on the 1st of January, and 
snow scarcely covering the ground was to be found in the valley. This section connects with 
the Bitter Root valley. We thence followed down the Hell Gate river, from its head to where it 
debouches from the mountains five miles above its mouth; which we found to be one hundred 
and twenty miles long, flowing through a fertile, well-timbered valley, from two to five miles 
wide, bounded on each side by high pine-clad mountains. Game is found in great abundance in 
these mountains, being principally elk and bear. 
“A detailed description of each portion of the route having already been given, I only deem 
it necessary to say that both routes travelled are perfectly practicable for wagons, but the return 
route is by far the better of the two, though from sixty to eighty miles the longer.” 
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