Extinct Glacier of the Salmon River Range. — Stone. 407 
Napius creek drains a large area on the western slopes of these 
mountains. It flows nearly west and is a tributary of Big creek, 
which flows north into the Salmon river. I have had opportunity 
to explore cursorily the upper twenty miles of this valle}', extend- 
ing to a point about seven miles west of Leesburg and down to the 
elevation of about 5,700 feet above the sea. Here the river or 
creek, which is a large stream during the melting of the snow, has 
cut a deep canon through a high northeast and southwest ridge of 
granite, and thence it descends steeply to Big creek by a series of 
rapids and cascades. This point is known as the Falls of Napius, 
and lies at the foot of the flat known as Bull of the Woods. East 
of this granite dike there is an outcrop of several square miles of 
volcanic rock, bordered by a broad crescent of schists, which in 
turn is bounded by a belt of granite. The alternation of diflferent 
rocks makes it eas}^ to distinguish drift from local matter. Into 
the main creek flow numerous lateral tributaries, from five to ten 
miles long. The area of that portion of the valley to be described 
is about 300 square miles. Near the main creek the hills are not 
usually more than 200 to 400 feet high, and thence the hills and 
ridges separating the adjacent valleys inse higher as we go upward 
toward the top of the range. Near Leesburg the hills adjoining 
the creek are unusually low, and thus there is formed a sort of roll- 
ing plain enclosed by higher hills. At one time all the higher 
valleys and cirques were filled by glaciers which flowed down into 
the main valley where they covered all the hills near the main 
stream, thus being a confluent glacier or ice-sheet enveloping not 
onl}' the main valley, but also a broad belt on each side extending 
back into the lateral valleys. The following four kinds of mo- 
rainal masses are found. 
1. Lateral Moraines. These do not take the form of distinct 
ridges or terraces on the sides of the hills next the main stream, 
but are seen as a sheet or diffused scattering of erratics. 
2. I'erminal or Retreatal Moraines. About two miles east of 
the Falls of Napius is a moraine beginning near the river and ex- 
tending northward up a hill to an elevation of about 800 feet above 
the stream. It takes the form of a low ridge with gentle side 
slopes and in places is 500 feet or more broad, with several outly- 
ing spurs. Most of the material shows evident glaciation. On the 
south side of the creek is a corresponding moraine on top of a high 
north and south ridge. Near the creek this moraine does not show 
