FROM FORT HALL TO HEAD OF HELL GATE RIVER. 343 
miles from our camp of last night, we crossed and found frozen to the bottom. This creek is so 
called by the Indians, who, some years ago, caught fish from its waters by spearing them. Jour- 
neying a short distance from this creek, and crossing a series of low sand ridges, we reached a 
long, level, and beautiful prairie called the ‘Deer Lodge,” a name given it from the great 
number of deer found in and near its vicinity. This place is a great resort for the Indians west 
of the mountains at all seasons, and especially when returning from the buffalo hunt, where they 
remain several weeks recruiting their animals, finding the greatest abundance of rich and luxu- 
riant grass. Through it flow two large streams—one of which is the main stream of the Hell 
Gate fork of the Bitter Root river—and a great number of prairie streamlets; thus rendering it an 
excellent recruiting rendezvous for the Indians with their large bands of horses. It is about fifty 
miles long north and south, and from twelve to fifteen wide, bounded on all sides save on the east 
by high pine-clad mountains, the summits of which alone are tound covered with snow. <A very 
slight fall of snow covered the valley. It is noted for the very small quantity of snow found on 
it during the severest winters known in the mountains, which gives it the principal advantage for 
wintering over the many prairie valleys of the mountains. Its many streams are all lined with 
timber, consisting of the cotton-wood, birch, willow, and the black-haw. Finding our animals 
very much jaded by their long march, we concluded to remain here a day to rest and recruit 
them, where they found an abundance of excellent grass. We saw, when entering this valley, 
large bands of antelope feeding. These, with a few mountain sheep and goats, seen on the 
highest peaks of the mountains, constituted the game of the day. We did not exert ourselves 
to secure any, since we had a great quantity of elk meat with us. ‘The weather to-day has been 
exceedingly mild and summer-like, at noon being very warm. ‘Travelling a distance of eighteen 
and a half miles, by a very excellent road, we encamped on the Deer Lodge creek, where 
we found good grass, wood, and water. We crossed, about two miles before reaching the Deer 
Lodge creek, another of the same size, called the Rock Bank creek, a name given it from the 
fact of its passing through a rocky canon near its head. This last-mentioned creek, together 
with a small stream called the Yellow Bank, rises in the mountains bounding Deer Lodge on the 
south from the main stream of the Hell Gate fork of the Bitter Root river. The Deer Lodge 
creek, which is one of its largest tributaries, near its head is fifteen yards wide, with a rapid 
current, channel-water eighteen inches deep, and lined near its head with the cotton-wood, but 
lower down with the willow, birch, alder, and black-haw. The mouth of the Deer Lodge creek 
was about two miles below our camp of the night. There is a second, and one of the largest 
tributaries, comes in from the east, and empties into the main stream ten miles below the mouth 
of the Deer Lodge creek. By following up this tributary to its head, you cross, by a very excel- 
lent road, a dividing ridge, and fall upon the main stream of the Jefferson fork of the Missouri, 
which road is often followed by the Indians to the hunt, thence by the three forks of the Mis- 
souri. About four hundred yards from our camp of this night occurs one of the most singular 
and interesting formations met with on our whole route. It is a conical mound, about thirty 
feet high, with an oval top, around whose base, from east by south to west, occur innu- 
merable hot or boiling springs. On the top of this mound is a spring of three feet in diameter, 
down which was thrust a pole twenty feet long and no bottom found. The water boils up from 
this spring, but does not run off. 
The mound is composed of a hard ligniform product, occurring in concentric layers, from one 
to four inches in thickness. I cannot call it a rock, though it is as hard in most places as rock. 
On its southern slope occurs an irregular mass of black scoriated rock, that looks not unlike 
coke, and when broken presents the appearance of, and when lifted gives evidence of, the 
pressure of iron. It shows that it has undergone great change by the action of intense heat. 
The surface on the southern slope is incrusted with a white salt about one-sixteenth of an inch 
thick. Breaking from this mass of scoriated rock a small fragment, I accidentally exposed a 
bed of this white salt, which apparently extended far into the interior of the mound. It is 
