IMPROVEMENTS IN RAISING SUNKEN SHIPS AND OTHER SUBMERGED BODIES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Henry Jubber at the Office of the
Commissioners of Patents on the 7th December 1870.
HENRY JUBBER, of 7, Eastbourne Terrace, Bayswater, in the County of Middlesex.
"IMPROVEMENTS IN RAISING SUNKEN SHIPS AND OTHER SUBMERGED BODIES."
This Invention has for its object improvements in raising sunken ships and other
submerged bodies. It is proposed by means of these air bags to reduce to a system
economical, expeditious, and effectual the raising of sunken ships, floating them
when stranded, and generally as a safeguard against very many casualties and
disasters at sea. Each bag is say 12 feet long by G feet in diameter (containing
378 cubic feet of air capable of lifting 14 tons of solid iron in water), elliptic in
form, made in four equal parts of the best canvas and india-rubber enclosed in a
three inch mesh net of half inch rope. Each bag has an aperture at the base, from
which descends an air tube two feet long, one inch in diameter inside, three inches
outside; this air tube is connected at right angles with a main air tube twice the
diameter, to which any number of bags can be attached to a tube of proportionate
length. The ends of the net are secured to a stout iron ring, from which projects
an iron arm four feet long. A steel hawser is made fast to the iron ring at the
bottom of the bag. Suppose there are a number of these bags, a string of them,
properly fitted and attached to a hawser, I will proceed to explain the mode of
working for raising sunken ships.
The vessel to be raised as she lays at the bottom of the sea is estimated to weigh
say 1000 tons, equal we will say to a lifting power of 75 bags, but at least one-
third more, say 25 should be added, making 100 bags (excessive allowance for
weight of apparatus and compressibility of air). The position of the ship to be
raised being known a steamer proceeds to the spot provided with the apparatus,
this she casts overboard, and by means of the air engine on deck inflates the bags
just enough to keep them on the water, a large circle many times greater than the
length and breadth of the sunken ship is then formed, three-fourths of the circle or
oval being made by the naked hawser, one end of which has been passed through
the self-acting loop of the other, the circle being now complete and the hawser or
rather hawsers, for there are two ends being crossed and free of the air tube, the air
is withdrawn from the bags and the apparatus slowly sinks, then a boat well manned
carries one end of the hawser, retiring in a direct line from the steamer gradually
017

page_text: narrowing the circle at the bottom until it is felt by the boat being brought to, that
the apparatus has encircled the ship and the self-acting loop has caught. Get the
end of the hawser on board and proceed to pump air into the bags with a gradually
increasing force, the bags slowly gaining a perpendicular position will raise the
levers attached to the iron rings, which while tightening the hold of the hawser
round the vessel will also keep the bags at a proper distance from its sides, saving
accidents; after pumping half an hour the great buoyancy of the bags overcoming
the weight of the ship it will slowly rise, then commence towing by the hawser to
the nearest place of safety, still pumping with a much diminished force; but as the
bags will be visible their state of inflation can be easily regulated. With promp
titude the actual process of raising the sunken ship need not take more than two
hours.
A
For floating a ship when stranded, approach the vessel at high tide, encircle her
with the apparatus, then wait till low tide and securely fix the hawser as low down
the hull as possible, wait again till high water, inflate the bags, and should there be
a rock six feet high or broad through the ship's bottom, it is calculated the great
buoyancy of the bags will lift the ship clean off; should they not do so at the first
attempt add more bags, in which case nothing need be allowed for their com-
pressibility, as the operation would take place in comparatively shallow water.
ship out at sea meeting with a like casualty and having the apparatus on board
could get herself off without any extraneous aid. Or much better still, if she were
properly fitted the length of her lower hold with a double row, cach bag enclosed in
a tube, she could in a few minutes, say 10, eject the whole of the tubes and fill the
bags with air, the number of bags always exceeding in buoyancy her own weight;
while being thus kept buoyant in a perfectly secure manner she could be repaired,
the bags drawn in, and proceed on her way, the bags fit at any moment for further
service.
In collisions or dangerous leaks the apparatus could be easily used from deck
when not otherwise fitted.
It is claimed for this system that if ships were properly fitted with these bags in
a double row extending the length of the lower hold so as to be ejected as low down
both sides of the ship at the same moment (always exceeding in buoyancy the
weight of the ship when loaded) a great number of the disasters at sea that are so
constantly being repeated would not happen, the saving of property consequently
proportionate, insurances could be effected at lower rates, passengers, crews, and
owners might feel a little more secure, and the saving of life could hardly fail to be
considerable.
Ironclads half riddled with shot, their water-tight compartments rendered almost
useless, in imminent danger cach moment of sinking, might still by this system be
kept safely afloat, the size, weight of the ship making no difference.
In case of fire the bags could be immediately ejected from the ship's sides, the
hull sufficiently filled with water to extinguish the fire, the water pumped out, the
bags replaced, the fire could not harm them as they would be several feet under
water, and the ship saved from probably the worst of all disasters.