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to ascertain the depth of soft material overlying the
rock and the nature of the rock by means of a trench right
across the valley opened along a line selected by Mr. Gourley
as possibly representing the best position for the Dam, and
work has been continued on this Contract upto the date of
writing.
It was arranged with the Crown Agents that Mr.
Binnie should inspect the rock when exposed, before final
approval was given to the selection of this site, as the
Dam would be of such a height as to impose heavy atresses
on the founation material.
Mr. Binnie accordingly arrived in Hong Kong on the
8th instant and has made four inspections of the rock as
now ex oded in the trench and hos also examined the adjacent
outcrops and the trenches excavated prior to Mr. Gourley's
visit.
The conclusion at which he has arrived is that
the site is a favourable one for the construction of a dam
of the proposed height and therefore he is able to confirm our
previous report.
The Reservoir when formed would be retained in a
basin the Southern boundary of which, between the site of
the dam and Pineapple Pass, is determined by the Hidge
from the Gin Drinkera' Bay
separating the Shing Mun Valley
drainage area.
If the Dum were
such a height as to impound
water up to 625 U.D. there would not be sufficient free-
board between the Reservoir level and the top of this Ridge
at one point, and Mr. Binnie is of opinion that it would not
be advisable to assume at present that the water was raised
by the Dam above 61ɔ 0.D.
It would be feasible to adopt the highest level of
625 0.D. but further works would be involved the extent