CHAPTER XV. 
Plan of Construction and Details of the Roads.—Estimate of Cost—Use of Wagon road 
in connexion with Railroad. 
I will now pass to the plan of construction and the estimate of the cost of the road. 
The difficult points, those which are obstacles to reaching difficult points, and the portions 
passing through a rich country, which will at once bring remunerative returns, should be located 
and attached at once. 
The rich, remunerative portions, are the country east from the Bois des Sioux and westward to 
the crossing of the river Jacques ; the valley of the Mouse river ; much of the country from Fort 
Benton to the mouth of Milk river ; the region of the Rocky mountains; a portion of the Spokane 
country ; the greater portion of the Columbia valley ; the region from the Columbia to the sound, 
and from the sound back, near to the Cascades, and that from Seattle to the Columbia river. 
The difficult points are the passes of the Rocky and Cascade mountains—the former involving 
a tunnel, the latter a tunnel by the Snoqualme, or a large quantity of rock-cutting of the Colum¬ 
bia ; the rock-cutting on Clark’s fork, and the heavy embankments and cutting in the Bitter Root 
valley towards its junction with Clark’s fork at Horse Plains, and the heavy sustaining walls of 
the defile ending in Hell Gate. 
Allusion has already been made to a nearer route from the Bois des Sioux to the favorable 
passes, by crossing the Missouri and the Yellowstone, as well as to a connexion believed to be 
practicable through the Black Hills with Council Bluffs. 
For a route from Council Bluffs to the Columbia valley and Puget sound, the road could be 
operated on in four sections: 
1. Council Bluffs to crossing of Yellowstone. 
2. Crossing of Yellowstone to mouth of Snake. 
3. Snake river to post on Columbia, and to Puget sound. 
4. Columbia valley, by the line of the Cowlitz, to Puget sound. 
For a route from the head of navigation of the Mississippi and the Great Lakes, by the Bois 
des Sioux, the crossing of the Missouri and the Yellowstone, the sections will be: 
1. St. Paul and Lake Superior to Little Falls. 
2. Little Falls to Bois des Sioux. 
3. Bois des Sioux to crossing of Missouri. 
4. Crossing of Missouri to crossing of Yellowstone. 
5. Crossing of Yellowstone to mouth of Snake river. 
6. Snake river to post on Columbia, and to Puget sound by Snoqualme Pass. 
7. Columbia valley by the line of the Cowlitz to Puget sound. 
The route explored by me north of the Missouri will have sections as follows: 
1. St. Paul and Lake Superior to Little Falls. 
2. Little Falls to Bois des Sioux. 
3. Bois des Sioux to vicinity of Fort Union. 
4. Fort Union to mouth of Milk river. 
5. Mouth of Milk river to the vicinity of the Great Falls of the Missouri. 
6. Vicinity of the Great Falls of the Missouri to mouth of Snake river. 
