The Virginia enterprise., 1900-08-03
UNCLE SANS FLOATING DOCKS
One of 5000 Tons Lifting Power for
tue AIxiers Station.

One Of $4,000 Tons Lifting Power for
the AlEicrs Station.
The largest floating drydock in the
world is now being built for the United
States government by the Maryland
Steel company, at it's works at Sparrow $
point, just below Baltimore, Nd This
dock, when finished, will be tOWed down
Chesapeake bay to the Atlantic, and
through the Gulf of Mexico to the Mis-
sissippi, where it will be stationed for
use at the naval station at Alyiers, La.
1t must be delivered to Uncle Sam by
November i, and in the event of failurt
on the part CT the company to complete
it by that time $500 for every delay of
- hours will be deducted from the con-
tract price Of $Sl0,O0O: The work of con-
structlng it is now being pushed to a fin
fenced otf, the foreshorc has been
scoOped to form 4 berth and the dredgeu
material arranged so as to form Il Golfer
dam. n platform OF timbers was laid in
the large hole, and two trestles were
erected to carry the tracks for the tray
plates. Tracks are laid around the berth
and piping for the compressed air by
which the riveting machines are worked
The complement to these arrangements
is a machine shop, built expressly for the
work in question.
When the work is competed the cofer-
dam will be cut through, and the waters
Of the Chesapeake, which will then rush
IN and float the structure, will make any
preparations for launching unnecessary.
The dock Will materially augment the
Importance Of the naval station 10 which
1t has been assigned, especially in view
Of the fact that the value of New
Orleans as base is steadily increasing.
The dock wal be powerful enough to Int
Il $4,000 ton vessel feet above the sur
face Of the water, and with the floor
awash it will be able to lift IL vessel OF
$4,000 tons with the same ease. 1t Will
be 4 very superior affair, not only in
point Of strength, but IN simplicity. 1t
will be furnished with three ponloonS,
as regards length, the middle pontoon
will measure 2+2 feet, and the two end
pontoons 141 feet and Is inch each. The
keel blocks will number 2O9, the walls
measure 3o5 feet and IS inch. and the
! weight Of the dock is to be o7Oy tons,
which when added 10 the 42O tons weigh;
of its equipment, makes Gl22 tons in ALL.
to make the maximum lift. With this
If mtadc, the stability Of the dock will
be from fifteen to twenty times that Of
Il ship anOat.
Acid or basic open hearth steel is ex-
clusively used, the timber walling Of
lSXlZ pine beng employed merely as
tenders. The enormous walls serve pri-
marily to give stability and to regulate
the; descent when the pontoons are SUBJ
merged. They inclose four water-tight
compartments, which contain the quar-
ters for the crew and the pumping ap-
paratus. Each wall has four pumps
with 4 separate eng inc for each pump
and Il separate boiler for each eng gine.
The piping, however, is SO arranged that
any OF the engines can be supplied with
steam from any of the boilers, an ad-
! vantage by which, with only engine, boil
cr and pump, the dock can still be lifted.
The entire machinery will be managed
by means of levers from valvehouse on
each wall.
The peculiarity of the dock is that the
bottom of any of the walls can be
reached by keeling. The middle pontoon
is large enough to raise the other two out
of the water, and can be released and
lifted out Of the water ITSELF There are
many manholes by which access to the
inside Of the walls and pontoons may be
obtained.
Two of the three largest docks now in
use are owned by this country. One
was built for Spain and taken to Cuba
shortly before the late war, and thus
came into Uncle Sans hands. The sec
ond largest is the commercial dock at
Stettin, Germany, which was built in
England by Swami & Hunter. The
third and largest is the American dock,
which was built by the London firm of
Clark & Stanfeld.
The need of a dock at Algiers is owing
to the fluctuations in the level of the
Mississippi. The zero mark on the