698
whisps of straw, [?], counterpressure
superior to that on the canal side
would necessarily force the gates
open; and as flood water would
[necessarily, struck through] give this increased
counterpressure, it would act of
its own accord in relieving the
sluices from obstruction caused
by the gates. This species of gate
applied as it is to the Rutmoo
Inlet acts as a self regulator, and
will, I doubt not, be found to be
efficient. The 28 side openings or overfalls have no gates, they
will be regulated by 4 planks
of 12 inches in depth each on the
same plan as is practised on the
[Tumna?] Canal works. These planks
are raised at the ends by hooks
run through an iron strap,
which forms a loop at each
extremity. It will be observed
that none of the sleeper appartus
is required until the depth of water
in the canal exceeds 6 feet.
Before closing the account
of the dam and inlet, which
are the leading features of the works
on the Rutmoo River, I must
draw[n, struck through] attention to the longitu-
-dinal profile as given in diag.:
III fig. 3, by this it will be seen
that the effective slope of the
torrent at the point where it
is intersected by the canal is
equal to 8.23 feet per mile or 1.87
inches per 100 feet in length. Now
looking transversely to the line
passing through the inlet, canal
channel, and dam; we find
that the length occupied by these
works is equal to 304.5 feet, or
that
EN