The morning times., 1897-02-14
Upside Down
Beneath the Waves

An ingenious contrivance for raising
sunken wrecks, which has just been in.
| vented by Felix Gaillard, "a Frencbman ,p
Bordeaux, is attracting Considerable aaen-
ton in the marine world as well as an,opq
| wreckers and divers From his experenca
| rs a practical diver Mons GaiIiard earIv
appreciated the numerous difficulties en-
countered In raising wrecks by the slow and
laborious method Of sinking caissons, bind.
| ing them 10 the hull aud slowly ratslne. n
| To the surface. Often, when his ,Iirficult
| task was nearly completed, a slight leaI,
in one Of tie caissons would allow the huu
| to sink back 10 the bottom.
As boy lie had been familiar with tho
| principle by which, when an inverted Gun
Is forced beneath the surface of the water.
| Tie air pressure within the vessel keans
| it dry and prevents the water from fjlIinp
it. THIS was the first idea of the French
| inventor, and it is tie Fundamental urinci
| pie OF the Gaillard system Of wreclt-raisinr
| TIE completed result is simply a number az
waterproof bags made In the shane of bup..
| cylinders or pipes, long tubes which connect
these bags with a powerful air pump, and
some stout pieces OF canvas aud Chains
The air pumps used in this wreckipe
machine are much more powerful than tho
| ordinary Kind and are carried in the stern
OF Stanch ocean going tugs The engines in
these tugs are so arranged that whenever
il i $ desired they can be connected with the
air pumps The air is forced tbroupb
draught pipes into a huge below S-llke ar
rangemcnt made of steel, wood, canvas and
leather, and reinforced at every possibIe
point with Il double thickness of each
| material 1t is circular in form and held in
position between two horizontal steel
plates which are connected by powerful
screws
When the ar is forced into the drum it
naturally expands and forces the two steel
plates, between which it is helG apart
After it has been completely filled with
air the huge screws which connect the
rims Of the plates are turned by the en-
eines, and by screwing the two plates to-
gtthcr d Powerful Pressure is Brought to
bear, ana the air within the drum 5 forced
out through the pipes which head TO the
cyiindcriikc bags. and tie large main Uire
which forces the water from the suEken
hull Automatic valves prevent the air be-
ing forced back through the pump.
When 2 wreck is tn be raised by this
method. the cargo, il there is auy. is
first removed, and a tug, supplied with
air pump. bags and The rest OF the equip
rIeut. Is cnt 10 the place where the ship
went down and anchored little TO one
size. on the tug is carried a completc
divers outfit. When the disaster has
been oocasoned by collision ar by strik-
ing submerged reef and the ship has
s!i back INTO deep water, there are holes
in the hull to be repaired before ANYTHING
eau be done toward bringing the craft to
tie surface.
1T is here that the large pieces of canvas
which are q portion or the outfit are in
diSpensable. With them the diver patches
as lightly a> possible the hClcS IN the hull
ana at the same time opens ali the matches
Of the sunktn ship, and makes fast within
tie hull he large main pipes which cor
nee. with the huge air drum on the tug
The next step is to make fast to the hall
in the secureSt possible manner the nulner.
Gus cylindrical bags. These are sent down
TO the diver. who, with chains, binds
them along the keel on either side. These
bags are connected by stout pipes with the
air pump above and when all are made
fast the powerful machinery Of the tug
connecting with the pump is set in motion.
As the bags gradually fill with air under
the influence OF the powerful pressure from
above they exert 4 lifting power on the
hull which is not to he Resisted Gradually
the huge frame is completely turned over
and eventually rests on the bottom Of the
sea, up side down.
Meantime the large main pipes which
were first made fast inside the hull have
not been idle and as the powerful and
steady current OF air is forced through
them into the hull, the water is gradually
forced out AS the air pressure increas ses
the hull becomes lighter and rises toward
tine surface Air being constantly forced
into the hull and the bags strapped along
the keel, the pressure is maintained and
the water kept out on exactly the same