REPORT AND ESTIMATE. 347 
but as much of the slope consists in debris, workable with the shovel, embankments will be 
easily made, and when constructed will be of the most durable kind. 
At eastern prices this work might be done at fifty cents per cubic yard. The tunnel through 
Cape Horn mountain would cost, at eastern prices, say, sixty-five dollars per lineal foot, a high 
estimate, considering the character of the road. The easy access to this part of the route will 
make it cheaper of construction than parts of the same character further in the interior. 
The bluffs along the Columbia cease near Cape Horn, and passing through a level bottom 
land, partly wooded, as far as the Cowlitz, it turns northward from the Columbia, and follows 
the wide Cowlitz valley, with an easy ascent, to the prairies occupying about half of the country 
on the line from thence to Puget Sound. Along the eastern shore of Puget Sound, from 
Steilacoom to Seattle, it passes through dense forests for most of the way, and crosses several 
large streams, which will probably make a terminus higher up the sound desirable for a route 
approaching by way of the Columbia. Good building stone, excellent timber, and abundant 
water is found on this part of the route, while fine gravel, constituting the soil through most of 
the way, offers a superior material for the road-bed. But Lieutenant Mullan reports that, by 
his Wagon Pass, a railroad line can be laid across the Rocky mountains with only a cut one 
hundred feet deep through the divide, which is but half.a measured mile from base to base, 
and that no excessive gradients will be required on the eastern approach. The descent down the 
valley of the Little Blackfoot and Hell-Gate is exceedingly favorable. Thus a line can be laid 
down from the Mississippi to Olympia, on Puget Sound, with but short and few tunnels, but 
which will be two hundred and seventy-six miles longer than the route by Cadotte’s, the Cœur 
d' Aléne, and the Snoqualmoo Passes to Seattle. We cross the Rocky mountains by the northern 
Little Blackfoot or Mullan's Pass, then follow down the Little Blackfoot and Hell-Gate valleys, 
cross over the Jocko divide to Hell-Gate, follow down Clark's Fork to below the Pend 
d'Oreille lake, cross over to the Spokane, and, finally, after passing over the great plain of the 
Columbia, follow down the Columbia valley to near the mouth of the Cowlitz, and теки the 
sound by the easy and practicable line of the Cowlitz and intermediate country. If, instead of 
a cut of half a mile through Mullan's Pass, this distance should have to be tunnelled, the only 
three hundred yards in length, fifty per cent. in 
remaining tunnels will be at the Cabinet, | 
basaltic trap, and Cape Horn, seven hundred feet in length. By this route the distance to 
Olympia from St. Paul will be two thousand and forty miles, against one thousand seven hun- 
dred and sixty-four miles, the distance to Seattle by the route of = tunnels. 
The distance to Seattle by the no tunnel route will be 2,092 miles. 
By the tunnel route the elevation above the sea is as follows : 
BRECKINRIDGE TO SEATTLE. 
Number of miles at an elevation above 0 and less than 1,000 feet--------------- 130 = 
Number of miles at an elevation above 1,000 and less than 2,000 {ее&........... 433 
ЕЗ EI eer d Зо 2,000---- me ео ОД be 
Didi. s ы do с. 3,000... do «+++: 4,000 feet .......... 18€ — 
o" „ол docs ak ‚000..... do ++. 5,000 {ее&$....-...... LE o 
е а: 5,000 and above «sem 6 3 
d ee NN са ад a 
Do 
Summit level, 6,046. 
Tunnel at an elevation of 5,161.52. 
