Polynesian. [volume] (Honolulu [Oahu], Hawaii) 1844-1864, 1850-06-15
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lubrity Of the water be presumed to depend
upon Its freedom from organic matter, the
Mapledurham source would appear to be pre-
ferable, as in the seventeen miles between
the points Of abstraction, Henley, Reading,
Wargrave, and some villages, drain into the
river. On the other side Of the question, II
1 is to be noticed that the Loddon and Kennel
join the Thames below Mapledurham and
above Mednunham. d~das hassain
We propose therefore, to calculate upon
the abstraction Of loo, ,OOO, 600 gallons pei
twenty-four hours stated by the Henley pro-
equal qrantity, except in times of drought
for sewerage, as has been stated.
The termination Of drought and the COM
mencement of surplus in the river, with the
works for regulating the additional discharge,
should be determined in manner to be ap-
proved, and afterwards to be inspected and
controlled by you. -sas'e1 dl aas iillzaI
Now the effect which the abstraction will
have upon the navigation, both of the locked
part above Teddington and the tidal part be-
tween Teddington and London, being depend
ent on the proportion which the part abstract
ed bears to the whole Of the river water, we
have endeavored, by former measurements
taken by the late and the present Mr.. Ren-
ME, by Mr.. Simpson, and now by Mr.. Black
well and ourselves, at different times, to as
certain the natural discharge of the Tharces
during such drought as not unirequently
occurs. 1ola 1a.i s.l oi sss.5. 3-5.r
At Staines, the head Of your district, we
consider the quantity that may be taken at
from $50 to 4OO, ,OOO. 900 gallons per day !;
and at Teddington, eighteen miles lower, in
which space the Colne, Wey, Mole, and
Hogs Mill rivers join the Thames, at from
500 the $50 ,OOO. 900; so that in round num-
bers, the abstraction near Staines will be
one-fourth, and at Teddington one-f(th, of
the whole natural discharge Of the river. In
1876. very dry time, it was only 2sl ,OOO,-
900 near Staines by Mr. Leach's measure
ment. -.
AS Mr. Blackwell made the river at Hen
ley, during the shortest water of this year.
345 ,OOO, 600, it may be fairly supposed that
at Mapiedurham, which is above The junction
of the Kennel, it did not exceed 300, ,OOO, 600;
so that the abstraction of lOO, ,OOO, 900 would
be one-thrd of the whcle river during sea-
sons of drought. This is more the business
of the commissioners of the upper districts; !;
but if the navigation of their portion of
the river be damaged, the effect upon the
trade would be nearly the same as if the
evil was done in your own district.
To enable us to judge as to the effect of
the distractions, correct sections of the bed
of the river, and of the depths and inclina-
tions or slopes of the water in the lengths
likely to be effected, were Indispensable
We again employed an engineer to complete
the levels and sections from Staines to Ted
dington, which he began in the spring, and
Mr. Smith to assist US in the surveys for the
sections below Teddington. These have oc-
cupied considerable time, and have been
made with great care. -s'a 30. ~ b @
The diminished water would have the ten
dency to increase the growth Of weeds and
the settlement of deposit in all the periods,
but we think it would not exceed tendency,
as the water is clear during the times of short
water; at any rate, it is not a matter which
we can reduce to quantity, and the same OBJ
servations as to effect, will apply to the re-
duction of depth in the length of the periods,
some of which are barely sufficient for the
barges, the standard summer draught Of
which is three feet and ten inches, and they
often exceed this. s... ne
The effect of the tideway below Tedding-
ton lock comes to be considered separately.
This lock, when built in 1910, had six feet
upon its lower sill at low water in times of
drought. The removal of London bridge and
the deepening of shoals near London, have
lowered the water, so that there is now only
three feet and nine inches upon the Tedding-
ton sill, Ia reduction Of two feet and three
inches and the reduction would be greater
if the shoals between London and Teddington
were removed; for although these shoals i'm
pede the passage of barges, they assist in
preventing the water over them and up to
Teddington from falling lower, which is one
Of the causes Of their not having been re-
moved by you. In this case therefore, the
river wafer which follows the descent or ebb
of the tide, is valuable both as respects get
ing over the shoals and keeping up the wa
ter upon the Teddington lock sill. MIR. Leach
has calculated that the effect of abstracting
100, ,O00, 600 gallons would be to lower the
level of the water at the lock and for dis
tance downwaIds seven inches, which would
be real and practical evil.
II is proper to state that the above evil is
not, in our opinion, without remedy, for by
the removal of Teddington lock, and erect
ing a new lock near Kingston, or about a!
mile above Teddington, with sill of suffl-
cient depth, removing the shoals so as to en-
able the tide to flow more freely up 10 the
proposed lock, and deepening the river up to
it, the abstraction of water would be COM
pensated for, and the navigation OF the
Thames improved by the greater quantity
Of ida! wafer which would flow and ebb al
every tide. t-t,
By the removal Of the Teddington lock to-
near Kingston, as above recommended, the
drains of that and the low grounds near It
would empty into the fiyer below the lock
which would, it is considered, be an improve-
ment to Kingston and the low grounds near
it. The suggestion for the removal OF led
dington lock aud Of the shoals is not new;
all that is meant to be said. IS that the pro-
posed abstraction for wster works VIII m