248 GEOGRAPHICAL MEMOIR. 
Lewis and Clark’s Pass is but a few miles north of Cadotte’s, and connects the more northern 
branches of Dearborn and Big Blackfoot rivers. Its elevation is 6,519.3 feet, and it also hasa 
narrow ridge, only two miles and a quarter from base to base. The most northern pass, 
supposed by Mr. Tinkham to be the Marias, connects one of the principal sources of Marias 
river with a branch of Flathead river on the west. The approaches on each side are through 
deep mountain ravines, and a wall-like divide over 7,600 feet high separates the streams of 
opposite sides. A tunnel might be made at about the elevation of 5,450 feet, but as the branch 
of the Flathead falls 2,170 feet in seventeen miles, this route is not likely to be used. The 
pass last described is not, however, the true Marias Pass, for after leaving it and coming upon 
the chief tributary of the Marias, and moving southward eight miles, the true Marias Pass is 
plainly discernible. The true Marias Pass connects with the Badger tributary of the Marias, 
is wide, open, and easy, so far as it was examined by Mr. Doty in 1854, and as described by 
the Little Dog, the particulars of which are given in the narrative. It is probable that another 
pass, intermediate between the Northern Little Blackfoot and Cadotte’s Pass, will be found 
entirely practicable, and it should be examined. The passes which lead to the great plain of 
the Columbia are the southern Nez Percés trail, to which reference has already been made, 
leading from the upper waters of the Bitter Root; the northern Nez Percés trail, the route pur- 
sued by Lewis and Clark in their great explorations, and which was followed by Lieutenant 
Mullan on his return trip in 1854; the Cœur 4” Aléne or Stevens’s Pass, pursued by me in 1853; 
and Clark’s Fork, pursued by Lieutenant Saxton and the main train in 1853. Тһе following is 
a brief description of these passes: The southern Nez Percés trail goes up the southwest fork 
of the Bitter Root river, and crossing a dividing ridge, winds about over the summits of the 
high and rugged mountains separating the Kooskooskia from a more southern branch of Snake 
river, taking a very circuitous course to the junction of the main forks of the Kooskooskia. 
At the point where Mr. Tinkham’s observations with the barometer ended, it had reached a 
summit over 7,600 feet above the sea, probably the same point where Lieutenant Macfeely 
found snow early in September. This is a mere Indian trail, which avoids the densely wooded 
valleys, and goes over the mountain summits, where the elevation prevents the growth of trees, 
and substitutes a growth of grass. Should it ibe found practicable to cut a road down the valley 
of the Kooskooskia, the divide between it and the Bitter Root is here still nearly 7,000 feet in 
altitude, making more northern lines preferable. The distance over mountains by this route 
was estimated by Mr. Tinkham to be one hundred and thirty-eight and a half miles. The 
northern Nez Percés trail is in character much the same, but its course is more direct. It 
passes up the valley of the Lou-Lou branch of the Bitter Root, (Traveller’s Rest creek. of Lewis 
and Clark,) and, crossing to a northern branch of the Kooskooskia, winds along the heads of 
branches flowing into this and the Peluse (?) in a southerly direction, till it comes out on the 
Great Plain on the same place as the southern trail Тһе distance travelled across mountains 
by this route is about one hundred and twenty miles. The mountain dividing the waters which 
Slow: east and west is lower than some of those crossed in going up Lou-Lou creek, but covered 
with pine and fallen timber. 'Fhis may be found a tolerable wagon route from valley to valley, 
if the timber which now obstructs them shall be found the only obstacle. —  - 
The Cœur d’ Aléne or Stevens’s Pass, leading from St. Regis de Borgia creek, (which empties 
into the Bitter Root river about half way between the Jocko cut-off and Horse Plain,) takes a 
wost-abrihwost direction up that stream, and crossing a divide only 5,089.7 feet above the sea, 
continues in the same course down the Cœur Ф Aléne river to the lake at the border of the Great 
