The times-herald. [volume] (Burns, Harney County, Or.) 1896-1929, 1915-07-10
GREAT DRyDocKS.
Where the Largest Warships Can
Be Repaired In Safety.
HUGE BASINS OF CONCRETE.
Into These the Vessels Are Floatod and
shorsd Up ss the Gates Are Closed
and the Water Pumped out-Float'no
poeks and How They Are Used

Into These the Neeseie AVo T'o"NU" NV
shored Up ss the Gates Are Closed
and the Water Pumped out-Float'n9
poeks and How They Are Used,
There Is no such thing rs n perfect
anti.fouling composition, and probably
there never will be.
by "anti-fouling" we mean solu'
tion which. applied to the bottom of
ship, will keep her clean for an indeh-
mite period.
True. vessels eau now keep the sea
for months ON end without getting foul
enough TO seriously diminish their
speed, but In the long run their bot
toms become weed grown, and they
are obliged to go inte dfydock aud be
scraped and cleaned and repainted.
In old days, when warships were no
larger than the steam launches which
now hang on Dreadnoughts darits.
the seamen did this work themselves,
They ran the galley on TO some con
venient beach, hauled her out, tipped
her on one side on the sand, scrlped
her and caulked her seams.
hNtu III tht tikhtcthth NNh'"S N"f
tain Cook "careened" his vessel In n
tidal creek on the Australian coast and
did necessary repairs. The enormous
waships OF today require very differ
ent handling. and II is for their use
that dockyards are 6tted with dry
or craving docks OF vast dlmcn'
sions.
"a. l.. h.,.w Anal l. tnl
In the ground. 1t Is lined first with
masonry Of immense thickness, and
this In turn Is coated with thousands
OF tons of concrete.
The first great requisite OF dry
dock is to be dry, and as II is always
cut In low. swampy ground. with the
bottom far below low tide mark. this
Is the great difficulty before its build
ers.
The bottom IL quite fiat. The sides
run up In steps-enormous steps, each
about yard high. not the sort of stair
case to run down In a hurry,
These steps are known as "altaTs,'
and they have two separate purposes
first for supporting the workmen's
o(hhOiub, Tue btCOuu anu
tant for the fixing OF the shores"
Shores are the great balks OF timber
which hold vessel upright In drydock.
A drydock does not usually open
straight out OF the sea or harbor, More
often there Is n wet dock between.
The reasons are that vessel can then
be docked at any state of the tide and
al Nhne L., tl,.s
great watertight gates OF the drydock.
The actual process of docking I'm dry
dock is simple enough The drydock
Is filed with water, the ship Is tloatel
In. the gates close behind her: then the
water is pumped out by means Of pow
erful steam pHmps.
Along the bottom OF the dock runs In
a straight line Il row of keel blocks on
which the keel OF the vessel rests. AS
the water Is pumped away IN army Of
workmen fix the shores In position.
This is task which requires great
care. Not so very long ago M 5000 ton |
cruiser which was being drydocked at |
one Of the southern doekyards in Eng
land was so carelessly shored up that
ehc bhpptu uuu topplti ONtI.
The damage was appalling The huh |
of the ship was badly injured. II cost |
many thousands OF pounds to repair |
her
There are also floating craving docks. |
There is one at Portsmouth with an |
area OF two and one-quarter acres and |
a lifting capacity Of 32OO0 tons. 1t Is
100 Inno ,,sII. 70
cost was f264,00O.
The beauty OF floating dock Is that |
II vessel is badly damaged the dock
can go to the ship instead of the ship
10 the dock. Also even II the ship is
heeliRg over, 80 that she could not be
passed through the gates OF a stone
dock, the floating dock can take her.
The floating dock is simply large
cradle built In n series of watcrtight
compartments which can be filled or
emptied at Will. IL was invented by
George Rennie IN 1866. BY means OF
n floating dock a large warship can be
raised high and dry within three hours.
Aboard, life goes on as usual. while
the sailors floating home stands shOred
up in dry dock. Her decks are just
about level with the top Of the sides.
but between them and firm ground
yawns chasm at least forty feet deep
During wartime the work of clean
ing and repainting the under part OF
the hull goes on night and day, and
job that usually takes fortnight may
be completed within four or even three
Weekly.