140 GUIDEBOOK OF THE WESTERN UNITED STATES. 
The terraces of soft material, resting against slopes composed of the 
Belt series, show almost continuously along the valley of Jocko River, 
first on one side and then on the other, growing 
Dixon. stronger downstream. They reach their best devel- 
Elevation 2,531 feet. opment at Dixon, where the Jocko joins Flathead 
5 River, which comes down from the north. This 
river drains Flathead Lake, which lies 26 miles to the north and is 
one of the largest bodies of fresh water lying wholly within the 
United States. The river is navigable for small steamers from 
Dixon up to a point within a short distance of the lake, where 
rapids stop further progress. 
At Dixon the material deposited in Lake Missoula is fine white 
sand and clay, being the ‘‘rock flour,” or fine rock powder, which 
a glacier grinds from its rocky bed and which is carried off by the 
streams, giving them a milky appearance. It was brought down by 
Flathead River from the immense glacier that long ago occupied the 
entire valley of Flathead Lake and the country farther north, where 
the town of Kalispell now stands. This material was deposited in 
the waters of the lake in thin layers (lamin) that give to the cut 
edges of the material a banded appearance. It is probable that the 
‘glacier occupying Flathead Valley reached at its greatest extension 
nearly or quite to the place now occupied by the town of Dixon, but 
there is no evidence that it passed farther down the valley. 
At milepost 40 a more extended view than that obtained farther 
up the valley can be had of the Mission Range, including its highest 
summit, McDonald Peak, and a small glacier lying in a deep amphi- 
theater on the north face of the peak, where the ice is sheltered from 
the rays of the midday sun. This is the only glacier in the Rocky 
Mountains that can be seen from the Northern Pacific trains. (See 
Pl. XIX, B, p. 119.) This noble range marks the eastern boundary 
of the Flathead Reservation and is the western limit of a broad wil- 
derness of mountain ranges that extend to the margin of the Great | 
Plains and include farther north the rugged mountains of the Glacier 
National Park. The Mission Range was named from the Roman 
Catholic mission established at St. Ignatius, near its base, in the 
early fifties. The range can be seen by the traveler from a point a 
little west of Dixon to McDonald, and if the weather is clear the 
view can be relied on to hold the attention, especially from early in 
October until late in June, when the rugged outlines of the range are 
veiled under a shining cover of snow. The nearest peaks are about 
24 miles away and rise to heights of a little more than 10,000 feet 
