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are best developed on the northern slopes of the mountains because the
glaciers lying on the northern slopes were protected from the heat of the
sun. It is well established that a valley glacier, if it be sufficiently nour-
ished by snowfall to render it active, will erode the bedrock of the
valley in which it lies, partly by abrasion and partly by plucking out masses
of the bedrock which have been loosened by frost action—the latter action
taking place especially near the headwall of the cirque—and will transport
the material downstream. The present small glacier in the cirque basin
on the north slope of mount Agnes accomplishes practically no erosion,
but there is no doubt that the small drift ridges lying in the valley below
the glacier are moraines formed by this glacier at a time when it was more
active than at present, and that during the Ice Age the glaciers extended
far down the valleys and transported a large amount of glacial debris to
lower levels. Much of the glacial drift in the valleys was probably derived
in this way, and comparatively little transported by the ice-sheet which
at other times during the Ice Age covered the whole area, for, as already
pointed out, most of the drift in the several valleys has been locally derived.
It is, therefore, improbable that any pay-streak formed in the upper parts
of the valleys in pre-Glacial time could have survived the effects of glaci-
ation, at least in those parts of the valleys where glacial erosion has been
pronounced. Indeed, it is remarkable that the rich pay-streak in the
shallow ground of Antler should have escaped erosion by the glaciers if it
were pre-Glacial in origin.

Nugget Gulch

Nugget gulch, so named because of the numerous and occasionally
large masses of galena found in the pay-gravels, flows into Antler creek in
the southeastern corner of the map-area. It occupies a comparatively
narrow and steep valley in the lower part and a remarkably broad and
flat-bottomed valley in the upper part. A small rock canyon in which the
present stream flows near its mouth has been uncovered by hydraulicking,
but before mining operations were begun on the creek very few, if any,
rock outcrops occurred. In its upper broad part the valley is deeply drift-
filled, probably to a depth of at least 100 feet in places. The valley at its
upper end is cut off abruptly by the deep and steep-sided valley of Cunning-
ham creek. Its general appearance of being a river valley and not a valley
formed by ice erosion lends colour to the belief that it is part of the ancient
valley of Antler creek, formed at a time when the stream flowed at about
the level of the bedrock in the drift-filled upper part, and that the higher
part was captured and largely eroded away by Cunningham creek. For
this reason it was regarded favourably by prospectors for many years.
The elevation of the bedrock in the upper broad part is about 4,700 feet,
which is about the elevation of the broad bench on the west side of Antler
opposite the old town of Antler.

Considerable work was done in the early days in the shallow ground
near the mouth where there were two channels, one in drift and one a
narrow bedrock channel buried beneath a small thickness of drift, but the
deep ground above and the difficulty of controlling the flow of ground

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