GEOGRAPHICAL MEMOIR. 249 
Plain. In this pass the western ascent is the most rapid. The western base of the dividing ridge is 
of the same height as the eastern. The ridge will require a tunnel only 1$ mile through. Fora 
wagon road this is decidedly the best and most direct route, being almost in a line with Hell- 
Gate valley, and requiring but a moderate amount of work to make it practicable, chiefly the 
cutting out of timber in the valley. The route down Clark’s Fork crosses by the Jocko cut- 
off from Hell-Gate to the Flathead river, and crossing this, follows down its north bank in a 
northwest direction for 1651 miles to the south end of Flathead lake. The only mountain ridge 
which could not be removed in making a railroad by this route is that between Hell-Gate and 
the Jocko, which is a rise of 560 feet, requiring a grade of fifty feet in ascending and sixty in 
descending to the north. This would probably be preferable to following down the Bitter Root 
to its junction with the Flathead, as that is reported by Mr. Lander to require many crossings, 
rock cutting, and embankments, below the mouth of the St. Regis de Borgia. 
Lieutenant Donelson estimates that ten men, in seventy-eight days’ work of ten hours, would 
make this a good wagon road from Hell-Gate to the mouth of Pend Ф Oreille lake. Ап exam- 
ination of Lewis and Clark's narrative shows this curious incident: The Indians impressed 
them with the idea that the route which they pursued was altogether the most practicable of 
any route across these mountains, and yet it is unquestionably the worst route of the whole. 
They adopted the same policy in reference to these passes which they afterwards did in the 
Yakima country with the parties of the exploration. Indeed, so tenacious not only are the 
Indians, but even the missionaries, of their right of occupation, that it is impossible for them to 
resist the inclination to underrate the country and the routes, in order to keep white people 
out of it. Now, this route of Lewis and Clark is frequently taken by Indians at the present 
day, not because it is a good route, but because salmon and roots are found higher up the 
stream than on any other route, and it is a route, therefore, which furnishes them their food. 
They get high up the Koos-koos-kia on this route large stores of salmon, indispensable to 
their subsistence on their way to the plains of the Missouri. There are unquestionably other 
passes across the Bitter Root mountains which future exploration will develop. Reference in 
the narrative is made to a probable pass from the Peluse, which has its rise in the main chain 
of the Bitter Root mountains to a few miles from the Bitter Root valley, and has a nearly 
straight course to the westward, through a wide, open, and heavily-wooded valley from fifteen 
to twenty miles wide. This pass may connect with the Lou-Lou Fork. The St. Joseph’s tribu- 
tary of the Coeur Ф Aléne river unquestionably furnishes another pass ; and there are passos and 
known routes from points on Clark’s Fork, just below Horse Plain, where you can pass into the 
Cour d’Aléne country. From the divide of the Rocky mountains to the divide of the Bitter 
Root mountains there is an intermediate region, over one-third of which is a cultivable area; 
and a large portion of it is a prairie country, instead of a wooded or mountain country. The 
following estimate gives in detail the areas of arable land, so far as existing киоск нов mere 
it to be computed: In the region watered by the Bitter Root river and its tributaries, not 
including Hell-Gate, the prairie region may be estimated at 3,000 square miles ; in that 
watered by the Hell-Gate and its tributaries, including the whole country south and west to the 
Bitter Root, but not including the Big Blackfoot, there is a prairie region of 2,900 square 
miles ; in that watered by the Big Blackfoot and its tributaries, the prairie тергов 18 1, 300 
Square miles. The country watered by the Flathead river, down to its junction with the Bitter 
Root, and thence down Clark’s Fork to the Cabinet, has a prairie region of 2,500 miles. The 
country watered by the Koutenay has 2,000 square miles of prairie. Thus we have, in round 
328 
