FROM CANTONMENT STEVENS TO FORT BENTON. 
349 
the Jefferson river from those of the Hell Gate river, the same general remarks will apply as 
those describing the country from the head of the Bitter Root river to Fort Hall; a series of 
mountain ranges, giving beautiful prairie valleys, through which wind streams from the mountain- 
slopes, that pour their tributaries into the Missouri and its forks. Leaving the ridges referred to, 
you again enter a different and milder region, through which flow tributaries to Clark’s fork of 
the Columbia. Here the soil is a rich loam; timber is abundant; climate exceedingly mild, 
even during the severest winter. We entered it on the 1st of January, and snow scarcely cover¬ 
ing the ground was to be found in the valley. This section connects with the Bitter Root valley. 
We thence followed down the Hell Gate river from its head to where it debouches from the 
mountains, five miles above its mouth, which we found to be one hundred and twenty-five miles 
long, flowing through a fertile, well-tiinhered valley, from two to five miles wide, bounded on each 
side by high pine-clad mountains. Game is found in great abundance in these mountains, being 
principally elk and bear. Additional description of each portion of the route having already 
been given, I only deem it necessary to say that both routes travelled are perfectly practicable 
for wagons, though the return route is by far the better of the two, though from sixty to eighty 
miles longer. I regretted that I could not have made a barometrical profile of the two routes, 
but this resulted from the fact that a barometer could not be dispensed with in the Bitter Root 
valley, where was being kept a regular series of meteorological observations, to ascertain the 
character of the winter in this region. Such points of the route that were of sufficient interest and 
importance to be noted particularly were faithfully sketched by Mr. Adams, the artist of the party, 
to whom I am indebted for the accompanying sketches. 
Truly and respectfully, your obedient servant, 
JOHN MULLAN, 
Lieutenant U. S. Army. 
Governor I. I. Stevens, 
In Command of Northern Pacific Railroad Exploration and Survey. 
26 . Report of route from cantonment stevens to fort benton and back, by lieut. 
JOHN MULLAN, U. S. A. 
, Cantonment Stevens, Bitter Root Valley, 
April 2, 1854. 
Sir: I have the honor to report, that in conformity to your letter of instructions to continue the 
exploration of the country between the Rocky and Bitter Root ranges of mountains, and the 
examination of the mountain passes between the 43d and 49th parallels of latitude, I left the 
Bitter Root valley on the 1st of March to examine a new route thence to Fort Benton, on the 
Missouri, and to ascertain its practicability for a railroad route, as also the passage of wagon- 
trains ; and at the same time to obtain a knowledge, from actual observation, of the depth of the 
snow and the character of the mountains generally at that season. 
Lieutenant Grover, in crossing the mountains in the month of January, had an opportunity of 
ascertaining the depth of snow up to that period; and I thought it adding another link to the chain 
of knowledge of the mountains to ascertain their character at a period two months later. I was 
led to believe, by information gained from the mountaineers and trappers in this region, that 
there existed a road from the Falls of the Missouri to this valley over which wagons could pass with¬ 
out difficulty; and having passed over and examined one hundred and twenty miles of the route 
in September, 1853, and found it practicable for a wagon-road, I placed full confidence in the inform¬ 
ation, and started with the intention that, should the route upon examination prove practicable, 
to bring with me a wagon from Fort Benton to this valley. And I have the honor now to report 
that I have been perfectly successful, and have found in the mountains a wagon-road, the advan¬ 
tages of which are equal, if not far superior, to any existing across the mountains. I had also 
