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position in the bottom of the shaft. The raises were then continued in the
other pumping compartment and the second pump lowered to the bottom.
The total labour cost of the operations was $3,138.62 and the time consumed
forty-nine days.! In 1907 a tunnel 7 feet lower than the old tunnel was
run from the shaft and mining of the channel again started. Work was
continued during the autumn of 1907 and following winter. The ground
mined during the final operations is said to have paid as high as 7 ounces
to the set, but although the mine was then fairly well equipped and a new
boiler had been brought on the property, work was discontinued, probably
because it was realized that the ground was not rich enough to yield adequate
returns for the very heavy expenditure—probably at least $300,000—
incurred in development work. If the maximum depth of the ground had
been accurately determined by drilling, the gravel shaft sunk in the first
place to the proper depth, and waterpower used for pumping, it is possible
that mining of the ground would have paid.

An interesting question in connexion with the mining operations is
whether they were done in the deep channel of Mosquito creek or in that of
Willow river. The operators held that the workings were in the channel of
Willow river, for the most northerly bore-hole in the valley flat of the river
showed a depth of only 50 feet to bedrock, whereas the deepest part found
in the driftings was 102 feet below the level of the collar of the gravel shaft,
which is 1 or 2 feet below the level of the bore-hole. Assuming that the
reported depth of the Oliver shaft is correct, the bedrock grade from the
Oliver shaft to the Willow River gravel shaft is about 5 per cent, which is
about what is to be expected if both shafts are in the same channel. There
is room for another deep channel on the north side of the Willow River
flats and it is possible, although it does not seem very probable, that a
somewhat deeper channel than the one mined exists. There is no reason
to suppose, however, that it would prove to be any richer than the channel
mined, for the latter is closer to the rich productive part of Mosquito creek.
Before mining operations began it was believed that the channel would
prove to be rich, merely because Mosquito creek was rich, for no reliance
was placed on the borings for determining the gold values in the ground.
The drilling was done with an hydraulic jetting machine and at that time
the science of testing ground for depth and gold values was not developed
to any great extent. This proved very unfortunate, for not only was a
costly mistake made in determining the depth of the ground, but the values
in the ground proved to be much smailer than were expected. A significant
feature of the mining development work is that it was fairly definitely
proved that in places where the ground is porous and 100 feet or more in
depth it is very difficult to drain the ground by pumping from a bedrock
shaft and tunnel breaking into the channel, and that very great pressure
develops in the workings because of the water pressure in the ground.
Strangely enough, it was found possible to drain the ground and relieve
the pressure almost entirely by sinking and pumping from a gravel shaft,
in spite of the porous character of the ground and the presence of a good-
sized stream flowing in the valley flat. The gravels are cemented in places
below a depth of 50 feet and their partly cemented character, in causing a

1Boursin, H.: ‘‘Puddling a Wet Shaft’’; Min. and Sci. Press, Jan. 25, 1908, p. 129.