IN MEANS OR APPARATUS FOR RAISING SUNKEN SHIPS OR VESSELS
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by William Henry Bliss at the Office of
the Commissioners of Patents on the 2nd December 1876.
"IMPROVEMENTS
WILLIAM HENRY BLISS, of Lewisham, in the County of Kent.
IN MEANS OR APPARATUS FOR RAISING SUNKEN SHIPS OR VESSELS."
According to the first part of my improvements I employ suitable receptacles
furnished with air-tight chambers and appliances to generate gas by the chemical
decomposition of water or otherwise after the apparatus is placed in the sunken
ship, so as to displace the water within her, and substitute a much lighter gas or
fluid.
In carrying out the first part of my Invention I employ air chambers, say three
yards square, or of other convenient size. To these chambers I attach a water-tight
box or receptacle containing water and coils of zine; this box has a nick or small
opening into the chamber, through which the gas passes to fill the chamber. The
sulphuric acid or other active chemical agent is added immediately before the
apparatus is lowered into the sunken hull, and in a few hours the chamber will
become fully inflated, and thus displace so much water. I use this process as the
second operation when all three methods are necessary to be used in combination.
According to another part of my improvements I raise a sunken ship or vessel by
means of hollow water-tight boxes, casks, bales, or bags of cork, dry sponge, or any
other suitable buoyant material, air or gas pontoons of suitable sizes to displace the
water in the sunken hull, which will then rise to the surface, and can be towed into
harbour.
In very difficult cases, such as H.M.S. Vanguard, in order to enable the
divers to place materials in the sunken hull, I employ oxygen gas combined with
the air supplied to them so as to impart greater vitality, and when all the water
that can be displaced (by reason of the great difliculty in placing the boxes or bags
in the ship) is accomplished I then by means of large pontoons or rafts formed upon
the air boxes or otherwise attached at low tide, with powerful steamers (attached if
necessary fore and aft) raise and tow the vessel into more shallow water, where the
loading can be continued until she floated, which she will do when about three parts
loaded.
In carrying out this part of my improvements I form the air-tight boxes of wood,
having a strengthening partition in the centre, of any convenient sizes, say three
feet by two feet and eighteen inches deep, or other suitable size. I use a peculiarly
constructed case or carriage of sufficient weight to sink the air boxes, and from
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page_text: which they can be easily placed in position. This heavy cover or carriage is fitted
with small wheels, two at each end, and two large ones in the centre, so that the
box may be tilted to an angle of 45 degrees, and being unfastened will slip out,
and rise in the hold, cabins, and other parts of the vessel, so that they may be
stacked, as it were, till they nearly fill the ship, when she will immediately rise of
her own accord. This is the first operation I employ.
If from any great difficulty the boxes cannot be placed in the hull in sufficient
numbers, and the air chambers be damaged in any way by nails or otherwise so as
not to be entirely effectual, then my next appliance would be large pontoon rafts
formed on air boxes that may be six feet square or otherwise, till each raft sustains
one thousand tons. I then attach pulleys, and by the aid of powerful steamers (the
first and second processes having materially lightened the vessel) tug her into
shallow water, where the first process may be completed, if necessary, which of
itself will flont her.