Evening star. [volume] (Washington, D.C.) 1854-1972, 1894-06-16
S EASICK VESSELS
It is Necessary for Them to Go
Into the Hospital.
ENEMIES OF SHIPS In THE sea
Some Device Needed for the Pro-
lection of Iron Vessels.
SOME SERIOUS CONSEQUENCES

The sea is a grand and yet a treacherous
mother to the thousands Of ships that sail
over its broad expanse. and after buffeting
with its storms. the ships must go to their
hospital for repairs. This hospital is the
dry dock and the doctors are the army Of
careful workmen who look over carefully
| and repair every faulty seam or broken rivet.
Salt water is teeming with parasites OF
plant and animal life that cling TO the bot
| toms of ships, eat slowly yet surely through
wood and iron alike, or rust Il away, while
they act as a check On the speed by vastly
increasing the resistance and friction OF the
water against the ship. The gods of the
| storms see everywhere" and pick out each
weak seam or faulty rivet. and slowly and
surely eat into the vitals of the ship. 50
that every few months II becomes neces-
sary to examine and repair the vessel TO
do this she must come out OF the water.
The dry dock Is just a great box OF wood.
| iron. or stone, connecting with the sea by a
great gateway. When the ship is really 20
enter. the gate is shut and the water all
pumped out then the workmen with prsc-
ticed skill place the great blocks st the bot
tom Of the dock for the keel TO rest upon.
taking the dimensions from the plans and
drawings of the vessel. These in place. the
| dock is flooded again, the gate opened. ana
the ship hauled in. The gate is now closed
again. and while the water is slowly pump.
ed out and the ship settles down. the dock
| ers pull her this way or that TIL she rests
evenly on the keel blocks; then shores. or
heavy wooden beams. are braced from the
| sides OF the dock to the sides Of the ship.
and as the water is pumped away the ship
r,r..ss toll fab .atns
| OF water" the bottom. which was below the
| water line, covered with sea weeds and
parasites. that hide the defects they have
| caused.
The Cure Process.
Then the workmen scrape and scour the
unwelcome barnacles and grass away. the
seams and rlvets are all examined and re-
| paired, a fresh coat Of paint goes on again,
and as the dock is again flooded the ship
| rises from her hospital bed and the wood
| en- supports are knocked away until She
| fioats out on the sea again healthy and
strong" to battle with wind and sea- and
| the enemies OF the flag she proudly flies at
| the peak.
When wood was used almost exclusively
| In building ships a very easy and conven-
lent means was found to protect the under
| water portions of the ship from the in
| sidious attacks OF barnacles and parasites
|
| by covering the whole bottom OF the ship
| with a plating OF thin copper, for the gal
| vapic action OF the salt water upoa the cop
per was to convert the ship and sea into a
vast battery where the copper became the
| negative pole and was slowly yet constant
ly eaten away. the particles. as they fell
| away. taking with them the barnaclcs end
| sea weed as fast as they formed on the
| ship, thus keeping the ships bottom ard
| sides always clean so that the speed was
| Lot cut down by dragging the barnacles
| and yards of sea weed through the water.
| Yet even then the copper needed repairs.
| faulty tmbers rotted and crumbled away,
| SO that every few years the ship had to go
| into dry dock and be thoroughly overhaul
| ed, each faulty timber replaced and rusty
bolt repaired, until no loophoie was left
| for the sea to work upon.
| But with the advent OF iron I'm the build
! ing OF ships the old means Jailed, for where
| copper was placed over the iron the iron
became the negative pole Of the great bat
terry and was eaten away. quickly Kidding
| the bottom OF the ships with many leaks
| Many devices were tried-;he underwater
| portions OF the vessels were covered with a
/ waterproof layer OF wood, which was then
coppered as before-but wherever there
/ was any metallic connection between the
/ copper and Iron the whole force OF the
| battery acted there, and holes were eaten
| In unexpected and Inaccessible rIace S.
bringing In an element Of uncertainty and
4 enforcing great care In ''sheathiag' the
4 vessels, as the coating OF wood is cai,eDi,
1 II
\ than ever to the dry dock
Skill OF Chemists of No Avail.
Then the various methods OF painting
the bottoms with protective paints have
been tried and are used In all Of The cruis-
ers OF our new navy. The skill OF hundreds
| OF chemists has been exerted TO find a
paint that would act as the COPPER Goes
4 and throw of the barnacles and sea weed.
4 Great prizes have been offered. and a fer
tune awaits the sue cessf5 dist o, crer OF such
1 coating for ships, yet, so far none has
| been discovered that acts completely, aud
the Iron and steel ships which start from
| port with freshly painted sides and bot
toms return In a few months covered with
barnacles and sea weed. which. as Il trails
| In the water. very materially cuts Gown the
4 speed and power OF the shin. Then she
| must be put In the dry dock and scrubbed
and seTsped and repsinted Sill worse
| than the harnacles and sea weed a. the
water itself when II finds an entrance. he
| II ever SO small. through the paint 10 the
| steel below. Slowly but surely II .ayts out
| a little pit. which extends sometimes al
most through the plate before the paint
| which can even then only be seen hy put-
ting the ship in dry dock and eyaInia,ns
every square foot Of her bottom plating.
A Sick Leave Necessary.
| This all shows arw necessary 4. A. fer ,h,
| ships to go to their hospital and how
| careful her doctors" should be for mill
| lions of dollars worth OF property and mil
| lions Of priceless lives are carried every
year on these messengers of the sea. -
| The greatest docks in the world are those
Of the great shipping port OF Liverpool.
| where the great stone docks with their
powerful pumping engines. stretch fer
miles along the water front The stone
docks are the best for. II soli,lly built.
they may last hundred years, and, In
fact, the old stone dock at Norfolk navy
yard. which is now In use was built when
| John Adams was President # the United
| States. Yet In America, where fortunes are
| made and lost in few years. We do 10,
| often build for future generations, but only
| Tor the present, hence many Of the docks
| In the United States are wooden affairs
| that though cheap at first soon Cos;
more In repairs than they did In building.
Another find Of dock frequently used Is
the floating dock. a great platform sun
| ported by water-tight caissons, which are
first filled with water and allowed 10 sink.
| until the ship can be brought over the plat
| FORM when the water is pumped out and
| the platform slowly rises borne nm NV ,ho