The Rhode-Island Republican. [volume] (Newport, R.I.) 1809-1841, 1825-11-24
From the New York American.
TIE DIVING BELL.

THE DIVING BELL.
The wet Docks Of Liverpool, however spa
cious and magnificent, are difficult of en-
trance. They are not to be- compared with
the East River in point OF commercial ac-.
conmodation. Liverpool has indeed sur
mounted the natural Inconvenience of the
Mcrscy, where the tide rises above twenty
feet, but this circ umstance allows of the ea-
| ~ constructions of docks. At New-York
the TIDE rises but six feet, and has hitherto
, forbidden all under water works.
So too the Dry Docks of Liverpool have
made repairing ships prompt and cheap.
Here they arc hove down ut much more de-
lay and expense.
A Dry Pock cbuld not be huilt in this
harbcur without the aid of coffre dam, nor
coffre dam in deep water without the aid
of diyihgbell. five may calculate from the
experience ofEngland, for example in this
instance Of Plymouth Dock, cohre dam a
lone would cost 1900 dollars
II is therefore a matter of real phblic in
tcrcst, that the shp-rail way, modern in
vention, will supersedc the occasion OF a dry
deck.
In walking hp the East River shore at this
time, the eye is first attracted by the tall
masts of a ship Of war lately built for the
Brazilian government; the first probably Of
l feet. And little farther on, two other
| frigates are seen on the stccks, said 10 Be
building for the Greeks. Beyond those n
busy scene appears on the ground of the
Dry Dock Company; and amongst other
nopeities, a diving apparatus. j will roN
coll it a bell, as It has no resemblance TO
to one. 1t is nearly hollow cube Of cast
iron suspended from the shears of n large
scow, strongly rugged, and equipped with
iron windlasses, which are admirably con
trived to increase greatly the power ofthe
few menwbich work them. This apparatus
for working under water has been con-
structed for the Dock Company by Mr..
Thomas, a shipwright, from England. ca
riosty led me ON board. found the bell
or chamber to be about feet long and 5
broad, two inches thick, weighing Eve tons
and that three men can conveniently work
in it. They 90 tc the depth of Ii feet, and
might descend to any depth in our harbour.
1t is lighted by twelve convex lenses, set
in the top, which collect and concentrate
abundance d'light so that the men can see
as well as in open day. They are constant
ly supplied with fresh air by double fore
ing air pump, in some respects cf a pecu-
liar construction. The pumps and wind
lasses require six men.
The work now in hand is to cut Of, trim,
shape or fix the heads of the piles. driven
firmly into the ground to sustain the ship
rail way, and the weight OF ship of any
size. The three men cut off ~ piles, and
shape 10 in the course OF day.
But it occurred to recollection, that the
old fashioned diving bell did not wholly ex-
cludc the water; the air compressed by the
surrounding fluid allowed it to rise within
IL inches above the lower edge; and | was
at loss to understand how the piles could
be cut of close to the ground III exact con-
formity, level and beyel in turbid water;
but the inventor, with whom found my
self conversing, explained 1t as being an
improvement in the instrument beyond that
known in England, whereby the water is
not only completely expelled from the cham
Der, but even from the grcund il covers,
when brought very near TO It; 50 that the
men do not work At all in the water. OF
course there can be no deficiency OF air,
though the valves are 30 contrived that the
men feel no blast
When the ways come therefore to be
laid down, they will be secured as perfect
ly as if on the dry land.
On Thomas's principle ofthc ship rail
way, it is probable there will be no difficult
ty in hauling out for repair the largest ship
in the navy; because, as he explains it she
will receive general and ample support
before she leaves her buoyant element.
Dry docks are extremely expensive; and
there can be no doubt this invention, with
such notifications a. it viii here haze, viii
be complete substitute for them.
Wdys to haul out upon, have been Gen.
sidered desideratuin, 1t appears, in our
naval establishments. An experiment was
made at Washington by Commodore Rodg-
ers. The Potomac was hung in chains. and
drawn out upon slides, the basis Of their
support: but how she IL TO be re-leunched
remains undecided--perhaps on a rau
way.
We may in Nsw-York congratulate our