44 
CONCLUSION. 
The plateau at the western hase .of Blue mountains, a point to which the South 
Pass line is readily brought hy gradients of (in excess) 50 feet per mile is above 
the sea. 3,426 feet. 
Thence hy the northern detour line, say... 4,000 “ 
By eastern approach to Blue mountains, Pass of Walla-Walla, side-hill line. 4,112 “ 
General level of first grand plateau of Snake river. 3,050 “ 
Second grand plateau. 4,201 “ 
Mouth of Port Neuf.... 4,409 “ 
Summit of line of rail at South Pass. 7,490 “ 
Plains of Great Basin, southern connexion line... 4,200 cc 
Level of general eastern approach, through the valley of Sweetwater river, to South 
Pass. 5,000 “ 
Fort Laramie, Missouri river. 1,280 “ 
These heights as above the sea, in proportion to the lengths of route, (not given) are in excess. 
It would he entirely out of place to apply the equation of grade hy maximum loads to the 
ascents and descents of this route, as compared with the northern route. The northern route 
is emphatically a line of ascents and descents ; of undulating grades, which are not shown 
hy the data of preliminary reconnaissance, hut would (with full through traffic) materially 
add to the working length of the road. It would he preposterous to apply such equations to 
the profile of the emigrant wagon-road, or make the profile of the wagon-road the basis of a 
detailed estimate. 
CONCLUSION. 
The broken falls and rapids of the Snake river, near the mouth of the Salmon (see sketch), 
were measured hy the barometer. 
The water falls 328 feet in a distance of 15 miles. 
At about (hy the river) sixty-five (65) miles above these falls occur those of the Shoshonees 
(so called). They have been rarely visited hy white men. At a distance of 12 miles, a white 
column may he seen in the plain, resembling the smoke of a fire. The sound of falling water 
is heard at a greater distance. The bed of the river is six hundred and twenty (620) feet below 
the surrounding level country. The water flows in a contracted channel of about four hundred 
(400) feet. The sides of the ravine are nearly perpendicular. The fall is one hundred and 
eighty-five (185) feet, and is slightly broken at a point fifty (50) feet from the upper level. Five 
hundred (500) yards from the foot of the fall occur rapids of eighteen (18) feet. 
The height of the American Falls, near Fort Hall, is fifty-four (54) feet. 
The exploration would have been still more extended, had the party retained its first effective 
organization. Of the whole number of men who accompanied me from Oregon, hut a single 
individual arrived with me at the Missouri river. This individual, Mr. J. F. Moffet, had con¬ 
ducted the meteorological observations of the extreme northern expedition. He gave his atten¬ 
tion to the same duty under the more trying circumstances of the recent exploration. He was 
a native of Virginia. He had educated himself from the proceeds of his own industry; studied 
as a lawyer, and was admitted to the bar of Washington Territory. In the performance of 
his last patriotic service, his system received a shock from which it never recovered; and he 
died, of the privations incident to a passage of the continent without the comforts of a train, 
after his arrival at Missouri river.* 
I am indebted to Mr. B. R. Thompson, Indian agent of the Umatilla; Mr. J. T. Jeffreys, of 
Mr. Moffet left a small family unprovided for. If the exposure and hardships of the frontier citizens of America are 
of too common occurrence to gain public attention, the exemplary conduct and resolution of this gentleman, ending 
only with his life, are entitled to this passing notice. 
