FROM THE DALLES TO SNAKE RIVER. 
33 
line pass to Fort Boise, by detour towards the north, through the valley of Snake river, gradi¬ 
ents would he materially reduced, and this broken country, in a measure, avoided. 
From Fort Boise to the valley of Bear river, the route is of nearly uniform character. The 
line would traverse a high gravel or sand plateau, requiring mere nominal grading to prepare 
it for the rail. A few spurs of the hilly country towards the south extend toward Snake river, 
and can he encountered by the line, and reduced at low cost, or readily avoided. The changes 
in level are very gradual, and occur in broad terraces of many miles in extent, gradually 
rising toward the eastern mountains. 
Brick clay occurs in quantity upon Katherine creek, (so-called.) The scarcity of wood in 
the vicinity would prevent its use; but the extension of a preliminary road over the broad 
surface of these level plateaux would transport all necessary material to any section required, 
at low cost. Sufficient timber exists in the vicinity of the line (a species of mountain fir upon 
the hilly country south, and stunted cedars upon all low summits) to allow the ready extension 
of a line of rail, by the laying of a cross-tie and rail upon the level surface. 
This section preserves its character in approaching the summit of the dividing range be¬ 
tween the waters of the Snake river and the Great Basin. The approach is very easy, and the 
summit itself is an elevated gravel plain. By gradually approaching along the mountain side— 
the position of which allows the adjustment of the line by regular curvature—this summit can 
undoubtedly he accomplished by a cutting of thirty (30) feet in gravel, and gradients not ex¬ 
ceeding fifty (50) feet per mile. A preliminary line could he extended over it, without more 
excavation than necessary for the adjustment of the superstructure. The descent to the plains 
of the Great Basin is more difficult than the rise from the valley of Snake river. It may he 
readily accomplished, however, at low cost. 
The whole country is open. From surrounding summits, the inclination towards the Pass 
and entire line of approach is distinctly visible. The route is remarkably favorable for 
railway location and construction. The chief difficulty to he apprehended, is from the scarcity 
of timber, both in the immediate vicinity of the Salt Lake, and over the whole section ex¬ 
tending to Fort Boise. This difficulty must be obviated by the use of a preliminary road; for 
the construction of which, suitable stone for masonry is found on the northern rim of the Great 
Basin. Timber occurs in average quantity in the mountains north of Snake river; for all the 
purposes of a preliminary line, it can be obtained in the vicinity of the route. 
From the need of the construction of a preliminary road to complete any railroad to the Pacific 
within a reasonable time, I shall therefore state that this second division of the route, or section 
extending from Fort Boise to Bear-river valley, or to the plains of the Great Basin, presents 
extraordinary facilities for the construction of a railroad at minimum cost; and that in the com¬ 
parison of the engineering features of the lines from Puget Sound, in an easterly direction, to 
Bear river, upon this southern, with an equal distance upon the northern route, the advantage 
is immeasurably in favor of the southern line. 
It may be reasonably affirmed, from this result of reconnaissance, that the extension of a 
railroad line from the Great Salt Lake City to Puget Sound, or from the route of a railroad from 
California to Puget Sound, is eminently practicable. The character of Columbia-river valley 
is severe; but it should be borne in mind that it is a pass or passage of the Sierra Nevada or 
Cascade mountains, and is therefore merely to be weighed in comparison with other passes, as 
incurred by all other lines. It is common to both the northern and southern routes to Puget 
Sound. It is the most severe section upon the southern, but by no means the worst section 
upon the extreme northern route. 
I may observe, in this connexion, that the Grand Pass of the Yakima river, or the Snoqualmie 
Pass, to which so much attention has been given upon the northern exploration, is in far better 
direction in extending the southern than as a continuation of the northern route to Puget 
Sound. By a glance at the sketch, it will be observed as occupying a direct line from the 
Walla-Walla to that terminus. 
