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comparatively slow circulation of water through them, may account for
the fact that it was possible to drain the ground. Also, the ground was
drained gradually during the process of sinking the shaft, whereas in the case
of the bedrock shaft and drives to the channel the full pressure developed
at once when the channel was entered and flows of water and mud occurred
which drowned out the pumps. Mining from the gravel shaft, however,
had the serious disadvantage that operations had to be suspended during
the freshet and about two months pumping was necessary each year after
the freshet, before mining could begin.

The Meadows

The Meadows or alluvial flats of Williams creek and Willow river
extend northwest for 5 miles from Weldon lake at the junction of Pleasant
valley and Williams Creek valley to Jack of Clubs lake, and are continuous
with the narrower flats of Willow river, which extend for many miles down-
stream. They vary in width from 500 to 3,000 feet and the surface for the
great part is remarkably even—for it is the result of alternate erosion and
deposition by the present streams—but here and there small “islands” of
glacial drift rise a few feet above the general surface. They show that the
valley filling is mainly glacial drift and that the Recent stream deposits
have no great thickness except locally. There are extensive and thick
deposits of tailings on the flats opposite the mouth of Lowhee creek and,
to a less extent, opposite the mouth of Williams creek proper. The surface
erade of the flats along a direct line following the general course of the creek
from the mouth of Mosquito creek to the upper end of the flats averages
only 0-6 per cent. Jack of Clubs lake is at the level of the flats and drains
into Willow river. Near the upper end of the lake there is a low divide
26 feet high, which is all that prevents the water from draining down Slough
Creek valley, a much wider and more deeply drift-filled valley than that of
Willow river at Island mountain. Jack of Clubs lake, as determined by
soundings, has a maximum depth of about 175 feet and a soft mud bottom.
The deposits in Slough Creek valley beyond the head of the lake are partly
morainie deposits of a valley glacier. It may be that a mass of ice occupied
the lake basin during the closing stage of glaciation and, being protected
by its position at the foot of the steep northwestern slope of Cow mountain,
remained for a long time and prevented deposition to any great extent in
the basin; or it may be that deposition by the glacier moving down Jack
of Clubs valley partly blocked Slough Creek valley and dammed the lake
at the upper end, while deposition by streams blocked the lower end. There
is no evidence that the lake occupies a rock basin—although it may be
partly so—for the valley of Slough creek is known to be deep at the mouth
of Jack of Clubs creek and lower down at Slough Creek mine and is, there-
fore, probably a deeply drift-filled valley throughout. The bottom of the
lake is considerably lower than the deep channel of Willow river at Mos-
quito creek. This greater depth may be due to ice erosion, or possibly the
main drainage of Williams creek was at one time by way of Slough Creek
valley—a view which is borne out by the greater width and depth of
Slough Creek valley as compared with Willow River valley. It is possible
also that the drainage of parts of the valleys was at one time in the opposite