CASCADES AND LINE OF SNOQUALME PASS, 181 
Good granite is found on the Columbia, about one hundred and forty mies above the mouth 
of the Yakima: it may occur at a less distant point. 
From the crossing of the Columbia to the commencement of the pine timber is a distance of 
ninety-six miles; the general character of the valley to this point is wide, open, and terraced; 
the ground of sand, gravel, or loose stones—but little clay, or vegetable mould; curves easy ; 
long stretches of straight road, perfectly practicable. In this distance there are five points where 
the hills come close to the river; making, at most, ten miles of side-cutting necessary. This cutting 
is generally in earth, loose stone, or trap-rock, easily broken into blocks. In addition to these 
five points, the last eight miles of the ninety-six will be principally side-cutting in earth, gravel 
and sand—the work light, and no very high side-slopes. In the first eighty miles from the 
Columbia the grade will be twelve and a half feet to the mile; in the last sixteen miles it will 
be eight and a half feet to the mile. By keeping thus far the north bank of the Yakima, the only 
bridges of any consequence required will be two, over streams each about seventy-five feet in 
width. 
At some place in this vicinity it would be advisable to cross to the south bank of the Yakima, 
which is here about forty yards wide; good crossing easily found; plenty of timber on the spot; 
stone for masonry within twenty-five miles by water. The road now keeps to the valley twenty- 
one miles farther on—four miles beyond Ksitkas; passing through an open pine woods; soil light, 
sometimes gravelly; about two miles side-cutting—grade eight feet to the mile. From the point 
now reached, there are two methods of passing the dividing ridge: 1st. By means of a tunnel 
four thousand yards in length, from the level of Lake Willailootzas, 2,993 feet above Vancouver; 
2d. By a tunnel 11,840 yards long, from the level of Lake Kitchelus, 2,388 feet above Van- 
couver. 
If the short tunnel be used, the road must, at this point, leave the valley, take a side location 
on the northern slope of the mountains bordering the valley on the south, and ascend eight hun- 
dred and ninety-five feet in eighteen and a half miles, giving a grade of 48.4 feet per mile, 
in fifty per cent. rock. The plateau of Willailootzas, one mile long, will be entered by a curve, 
with a radius of about two thousand feet, and the road pass along the north bank of the lake, with 
side location, in eighty per cent. trap-rock, easily worked. This lake should be partially drained ; 
its shores are steep, and of broken stone. There will be some little difficulty in preparing a 
proper depot for the workmen, tools, &c., at the entrance of the tunnel. The tunnel, about four 
thousand yards long, will pass through solid rock, (silicious conglomerate) and will debouche on 
the western slope at an elevation of about three thousand feet above the sound at Seattle. The 
road must now have a side location on the mountain spur bordering the valley of the Nook-noo, 
in about seventy per cent. rock, generally conglomerate; follow this valley twenty-nine and a half 
miles, then take the summit and northern slope of the low ridge separating Lake Mowee from the 
valley of the Snoqualme, and from that taking a spur running from the Nook-noo falls to those of 
the Snoqualme, reach the latter falls at a distance of forty-five miles from the tunnel—all in side- 
cutting, with rocks as above. 
The grade will be 59.8 feet per mile. 
With reference to this stretch of forty-five miles, and that of eighteen and a half miles on the 
eastern slope, leading to the tunnel, it is to be observed that the grades given above are on the 
supposition that a continuous grade can be obtained; but it must be expected that the grade 
will necessarily be broken, and be higher than the estimate in many places. 
From the Snoqualme Falls to Seattle is a distance of about 30 miles, of which the first ten 
must have a grade of twenty feet per mile at most; and the remaining twenty pass over a quite 
level country. 
Tf, instead of a tunnel from the level of Lake Willailootzas, we consider a tunnel from the level 
of Lake Kitchelus, the case will be as follows: 
Commencing at the point eighteen and a half miles east of Willailootzas, there will be eighteen 
