100 GUIDEBOOK OF THE WESTERN UNITED STATES. 
LOGAN TO GARRISON BY WAY OF BUTTE. 
West of the station at Logan a few outcrops of Madison limestone 
occur near the track, but these are soon passed; and then the only 
surface features visible from the train are the broad flood plain of 
Gallatin River on the north and a bluff composed of Tertiary lake 
beds on the south. The character and composition of these beds and 
also of similar beds found in most of the other broad valleys of the 
mountain region are well shown by the bluffs on the east side of the 
valley of Madison River and can be seen by looking back after passing 
milepost 3. Here the material is largely sand and the lower layers 
exposed along the terrace front are hardened into real sandstone. The 
coarse sand above is less coherent and is being used in the manufac- 
ture of cement blocks. Farther south the sandstone is limited to the 
_ part of the terrace, and all the material below consists of white 
iG as 
At milepost 5 the railway crosses Madison River.t On the right 
(north) is the thriving town of Threeforks, situated near and named 
from the three forks of the Missouri. This place was 
Threeforks. first visited in 1805 by Lewis and Clark,? who named 
Elevation 4,0s1 feet. the easternmost branch for Albert Gallatin, Secretary 
Population 674. 
of the Treasury; the middle branch for James Madi- 
St. Paul 1,063 miles. 
son, Secretary of State; and the largest and western- 
! Fifty miles tothe south Madison River | conception of the difficulties that beset 
iss in a narrow, rocky | them by reading a brief quotation from 
and supply current to the cities of Butte, 
Bozeman, Livingston, and Billings; to 
placer mines in the vicinity of the plant; 
and to the cement mill at Trident, below 
Threeforks. A dam is under construction 
on Madison River which will store about 
350,000 acre-feet of water in what is 
known as the Hebgen reservoir. It is 
estimated that this reservoir when com- 
pleted will —— the total present 
development along Madison River by 
about 23 (tat icaiopanier 
2? When Lewis and Clark reached this 
point in their journey up the Missouri 
lead 
tains that lay in their pathway could be 
crossed. mav some 
their notes written while they were at 
Threeforks: 
“We are now very anxious to see the 
Snake Indians. After advancing several 
hundred miles into this wild, mountain- 
ous country, we may soon expect that 
the game will abandon us. With no in- 
formation of the route, we may be unable 
at least such a pass as will lead us to the 
Columbia. Even are we so fortunate as 
to find a branch of that river, the timber 
which we have hitherto seen in these 
mountains does not promise us any fit to 
make canoes, so that our chief depend- 
ence is on meeting some tribe from whom 
we may procure horses. Our consolation 
is that the southwest branch [Jefferson 
River] can scarcely head with any other 
river than the Columbia, and that if any 
nation of Indians can live in the moun- 
tains we are able to endure as much as 
they can and have even better means of 
procuring subsistence.’’ 
