Polynesian. [volume] (Honolulu [Oahu], Hawaii) 1844-1864, 1850-06-15

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Mednunham proposed level.J An open cut OF
aqueduct, four and q half miles long, is to
convey the water from Mapledurham to Ca.
lversham, where four reservoirs, together one
hundred acres, and ninety-eight feet above
high waters are to be formed for purifying
the water upon DIR. Clark's patent process
Powerful steam engines are to raise the wa
ter from the reservoirs through three iron
pipes, each FIVE feet in diameter carried
across the river, and then into three smaller
reservoirs, and thirty-fiye miles from Lon
don, and at different levels, corresponding
with the levels Of the three districts into
which the engineers suppose London to be
|divided-the northern and western district
being taken at one hundred and twenty feet !;
the centre district, which comprehends the
city, at seventy feet; and the south and east
district at ten feet above high water. The
highest Of the small reservoirs is two hum
dred and fourteen feet above high water
mark, and the lowest one hundred and sew
enty-nine, the mean lift being one hundred
feet, which illrequire l, 100 horse power
The water is conveyed from the small reser-
voirs by continuation Of the three five feet
pipes to the Great Western railway, near
Twyford, whence they are laid by the side of
the railway, and pass over the Thames at
Maidenhead, over the Grand Junction and
under the Paddington canals to near Worm
wood-scrubs; here the high level pipe d.
verges, asd4esses under, and then by the
side of, the Northwestern railway to a re-
servoir at Primrose-hill, of three and half
acres, and one hundred and sixty mine feet
above high water The other two pipes. for
the middle and eastern levels, continue from
Wo-mwood-scrubs by the side Of the Great
Western railway at Paddmgton, and thence
along Wesibourne-terrace and Oxford-street
into a reservoir. in St. Giles, of one fourth
acre area, and one hundred and fourteen feet
above bigh water The third or lowest pipe
crosses the Thames at Waterloo bridge into
the southern district. The three great mains
or the. town reservoirs, communicate with
the pipes of the present companies. -aaE
The engineers 3 estimate for this scheme is:
for works, EI 200, 600; annual working ex-
penses, f2O, 600, ~
: The Mapledurham differs from the Henley
scheme in the two following important par
ticulars-that the Henley is now proposed to
be under commission, and to take posses
sion of the present companies works and
pipes, while the Mapledurham party give the
preference to joint stock company, although
their notices include both; and they do not
propose to do more than to bring the water
to the present companies, and sell it TO them
for the use Of their tenants, which the Hen
ley party formerly proposed. but have now
abandoned. In both cases, the pipes OF the
present companies would come into use, al
though considerable alterations would be re-
auired in them. The Henley party propose
to remove the pumping engines from their
present situations to assist in raising the wa
ter at Hampstead The Mapledurham may
with the same facility employ them for rails
ing the water into the reservoirs near Ca
versham.
We have stated that the Henley party cal.
cuIate on taking lOO, ,O0O, 600 gallons in twen-
tv-four hours The Mapledurham state their
intention at half the above, or $4,000 900,
which they consider as double the present
supply of the existing companies. This ap-
pears to be on the supposition of the present
quantity being only d, ,OOO. .O6O gallons, and
to have been taken from the statements Of
1884. + which are not applicable to the pre-
sent time. ..--... ...
We now come to consider the effects Of
the two plans upon the navigation of the rlv-
er, and in doing so we do not think It right
TO confine ourselves to what the parties pro-
fess as to the quantity they mean to abstract,
for if the whole of London is to be supplied
from one source, there will be no satisfaction
until the supply is ample and constant,
whether the source be Mapledurham or Hem
lev: and Parliament will naturally take this
into consideration, and give preference, so
far as quantity is concerned, to the plan
which has the greatest certainty in the above
respect. .8-
The present supply by the water conpa-
nies, IS stated in recent publication by SIR
". Clay, chairman Of the Grand Junction
to be "A, ,573, ,979 gallons per day,
so that the quantity has much increased since
1884. This has been caused partly by the
increase of population, and partly also by
The greater supply to each house. Is it not
probable that both the above causes, and the
demand for water for sewerage and other
sanitary purposes, will continue to operate
30 "a to render il prudent to allow for these
IN any great plan, and to consider the effects
which the greatest probable abstraction would
be likely to have, upon the navigation? 1t is
however, to be noticed, (and this was one OF
the objects of our describing the main fea-
lures in the two plans, that the Henley par
ty propose their works to be made at first for
taking double the quantity calculated by the
Mapledurham company; and also that the
Henley aqueduct, being chiefly open, can be
ever this should be required
at less cost than the Mapledurham, who have
to raise their water to mean height OF one
hundred feet aHd then pass it through thirty
six miles of close pipe. To increase the
number of pipes would add materially to the
cost, and TO double the quantity through the
same pipes, would require an increase OF
power much beyond the increase OF the
quantity.
To compare in detail the merits Of the two
plans, would require US to survey the lines'
which your instructions would not warrant
our doing; but having said this much on what