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the result of a change in the gradient in the stream below. In such cases
the increase in gradient of the stream below the canyon was probably due
to local glacial erosion producing overdeepening of the main channel as
has happened on Antler creek opposite the mouth of Wolfe creek where
the upper part of the canyon is post-Glacial in age and the lower part
probably late Glacial. Some gold was found on the rock benches along the
canyon, whereas little was found in the steep, narrow part of the canyon
itself. Even if a stream were eroding headward in a valley bottom contain-
ing a small thickness of gold-bearing gravels resting on bedrock, as was
the case here, there would be little gold in the resulting canyon, for even
the coarse gold would be pounded fine enough to be carried downstream to
places where deposition was going on. A similar action takes place in the
case of pot-holes in the bedrock. These rarely contain any gold because
the pot-holes are ground out by stones being whirled around by the water
currents and any gold in the hole is ground so fine that it floats away.
In the rare cases in which placer gold is found in pot-holes, deposition has
taken place after the holes were formed and the gold was necessarily fine
enough to have been transported by currents along with the sand and
gravel which fills or partly fills the hole.

In the lower part of the canyon just below Antler and for some dis-
tance below, deposition has followed erosion and a considerable body of
gravels occurs which constitutes the known dredging ground of Antler
creek. The gold is known to occur mainly on bedrock at the base of the
gravels. It probably was transported mostly along with the gravels,
which are partly Recent and partly Glacial in age, and has been gradually
concentrated on bedrock by the action of the water flowing through the
gravels. The porous character of the gravels on the Nason ground was
shown by the fact that it was found necessary to flume the present creek
when drifting of the ground was attempted. It has been stated, also, that
within one or two hours after a heavy shower, an increase of flow of water
in the underground workings was noticeable. The lower part of the channel,
near the bend above Wolfe creek, was probably enriched by gold derived
from the old channel through which the present deep channel of Antler has
been cut. This old channel, which extended as a bench along the left side
of Antler, crossed the site of the present stream and continued through
Whiskey flat to Cunningham pass.

An especially puzzling feature in the distribution of the placer gold
on Upper Antler creek is the fact that the rich pay-streak commenced
abruptly near the mouth of Victoria creek and although diligent search has
been made for its continuation in upper parts of the creek and its tribu-
taries, no gold lead at all comparable to it in richness has been found.
This is probably due mainly to the effects of glaciation. It will be noted
from an examination of the map and will be called to mind by those who
are familiar with the character of the country, that in the upland areas
of Bald mountain and mount Burdett, as well as in other parts of the
region, the streams head in the mountain sides in peculiarly shaped depres-
sions, which are clearly glacial cirques formed by ice erosion. That they
were formed by ice erosion and not by stream erosion is shown by the fact
that streams in unglaciated regions do not form similar depressions. They