AN IMPROVED MODE OF AND MEANS FOR RAISING SUNKEN VESSELS
Year: 1867

page_text: LETTERS PATENT to John Emery Gowen, of the Langham Hotel, Port-.
land Place, London, in the County of Middlesex, for the Invention of
"AN IMPROVED MODE OF AND MEANS FOR RAISING SUNKEN VESSELS."
Sealed the 20th March 1868, and dated the 30th December 1867:
PROVISIONAL SPECIFICATION left by the said John Emery Gowen at the
Office of the Commissioners of Patents, with his Petition, on the
30th December 1867.
I, JOHN EMERY GOWEN, of the Langham Hotel, Portland Place, London,
in the County of Middlesex, do hereby declare the nature of the said Inven-
tion for "AN IMPROVED MODE OF AND MEANS FOR RAISING SUNKEN VESSELS," to
be as follows:-
The said Invention consists partly in the employment of four floating cais-
sons, which are arranged above a sunken vessel in such a manner that each
end of the said vessel when the same is being raised is supported by chains
suspended from two of the caissons. The four caissons are moored above the
sunken vessel by strong anchors and cables, and are connected together by
ropes or chains secured to upright posts projecting above the deck. The
vessel is raised either by winding or hoisting machinery carried by the cais-
sons or by filling the latter with water and submerging them to a certain
depth and then expelling the water and raising the caissons and suriken
vessels together. The lifting chains are arranged to pass over pulleys sup-
ported to turn freely in strong iron bearings which are firmly secured to tlio

page_text: deck of the caisson, and the said chains are conducted over guide pulleys to
a windlass operated by any suitable steam or other engine. The chaius are
provided with means for locking or securing them to the brackets when the
plan of submerging the caissons is adopted.
The said invention consists also in the peculiar construction of the floating
caissons, whose materials must be proportioned and arranged with the utmost
economy in order that they may possess great structural strength combined
with extreme buoyancy. These objects are effected by the employment of
trussed or open girders, which extend across from end to end of the caissons
and are secured and arranged in such a manner as to brace the ends firmly
together and to give to the entire structure great strength and rigidity with-
out materially increasing its weight. The caissons are most advantageously
constructed of a rectangular form, their sides, deck, and bottom being covered
with strong planking. The trussed girders are constructed of timber, and are
arranged in the best manner to distribute the strain arising from the weight
being lifted over the entire area of the caissons.
The said Invention also consists in constructing such caissons with a
peculiarly arranged system of water-tight compartments or divisions provided
with such means for the admission and expulsion of water that the weight of
the caissons can be readily and accurately adjusted to counterbalance the
weight of the vessel being lifted. Seven of these compartments are by
preference formed in each caisson. Valves are placed in the bottom of these
compartments, whereby the water can be admitted as desired, and the said
compartments are also provided with other valves in their sides, whereby the
water can be allowed to flow from one compartment to the other and also to
a central chamber wherein a pump is fixed. These valves are provided
with suitable handles which extend upward into a convenient position to be
operated from the deck.
The said Invention further consists in the means whereby the chains are
adjusted below the vessel to be raised. This operation is performed by means
of a pointed rod which is attached to a rope and is pushed under the vessel's
keel. By means of the rope a light chain is drawn under the said keel and
then a heavier chain; the latter can be buoyed till the caissons are moored
in the required position and then passed over pulleys or drums projecting
beyond the sides of the latter. When a vessel is.embedded deeply in mud or
sand it will be necessary to remove a portion of the same before the pointed
bar can be passed under the keel. This object is effected by means of a flat
plate or scraper which is connected by a rope to a capstan in a vessel moored
in a convenient position over the vessel to be raised. The said scraper is

page_text: repeatedly adjusted by a diver and then drawn away by the capstan, a portion
of the mud or sand being removed at each operation till a channel or aperture
is formed down to the level of the keel for the introduction. of the pointed bar..
SPECIFICATION in pursuance of the conditions of the Letters Patent, filedi
by the said John Emery Gowen in the Great Seal Patent Office on the
30th June 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN EMERY
GOWEN, of the Langham Hotel, Portland Place,, London, in the County of
Middlesex, send greeting...
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters-
Patent, bearing date the Thirtieth day of December, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first. year of Her.
reign, did, for Herself, Her beirs and successors, give and. grant unto me,.
the said John Emery Gowen, Her special licence that I,. the said John Emery.
Gowen, my executors, administrators, and assigns, or such others as I, the
said John Emery Gowen, my executors, administrators, and assigns, should.
at any time agree with, and no others, from time to time and at all times.
thereafter during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for " AN IM--
PROVED MODE OF AND MEANS FOR RAISING SUNKEN VESSELS," upon the condition
(amongst others) that I, the said John Emery Gowen, my executors or
administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature of
the said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar.
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Emery Gowen, do hereby declare
the nature of iny said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings forming a part
of this Specification:-
The said Invention consists partly in the employment of floating caissons,
which are arranged above a sunken vessel in such a manner that each end
of the said vessel when the same is being raised is supported by chains
suspended from two of the caissons. The sunken vessel is raised either by

page_text: winding or hoisting machinery carried by the caissons or by filling the latter
with water and submerging them to a certain depth and then expelling the
water and raising the caissons and sunken vessel together.
The said Invention consists also in the peculiar construction of the floating
caissons, whose materials must be proportioned and arranged with the utmost
economy in order that they may possess great structural strength combined
with extreme buoyancy. These objects are effected by the employment of
trussed or open girders, which extend across from end to end of the caissons
and are secured and arranged in such a manner as to brace the ends firmly
together and to give to the entire structure great strength and rigidity
without materially increasing its weight.
The said Invention also consists in constructing such caissons with a
peculiarly arranged system of water-tight compartments or divisions provided
with such means for the admission and expulsion of water that the weight of
the caissons can be readily and accurately adjusted to counterbalance the
weight of the vessel being lifted. Valves are placed in the bottom of these
compartments, whereby the water can be admitted as desired, and the said
compartments are also provided with other valves on their sides, whereby the
water can be allowed to flow from one compartment to the other, and also to
a central chamber wherein a pump is fixed.
The said Invention further consists in the means whereby the chains are
adjusted below the vessel to be raised. This operation is performed by
means of a pointed rod which is attached to a rope and is pushed under the
vessel's keel. By means of the rope a light chain is drawn under the
said keel and then a heavier chain; the latter can be buoyed till the
caissons are moored in the required position and then passed over pulleys or
drums projecting beyond the sides of the latter. When a vessel is embedded
deeply in mud or sand it will be necessary to remove a portion of the same
before the pointed bar can be passed under the keel. This object is effected
by means of a flat plate or scraper which is connected by a rope to a capstan
on a vessel moored in a convenient position over the vessel to be raised. The
said scraper is repeatedly adjusted by a diver and then drawn away by the
capstan, a portion of the mud or sand being removed at each operation till a
channel or aperture is formed down to the level of the keel for the intro-
duction of the pointed bar.

page_text: for
horizontal section of the same on the line y, y, Figure 2; Figures 4 and 5
are a plan and side view showing four caissons moored together and a vessel
being raised by the same; Figures 6 and 6* show the pointed bar employed
in adjusting the chains under a sunken vessel; Figure 7 is the
removing sand or mud to allow the pointed bar to pass under the vessel's
keel; Figure 8 illustrates the manner of using the said scraper. Like letters
indicate the same parts in all of the Figures.
scraper
The floating caissons A are most advantageously constructed of a rectan-
gular form, as represented, their sides, deck and bottom being covered with
strong planks, or the said caissons may be constructed entirely or partially of
iron. The trussed girders 6 are constructed of timber and are arranged in
such a manner as to distribute the strain arising from the weight being lifted
over the entire area of the caissons. Each caisson is preferably divided into
seven compartments, which are separated from each other by strong partitions
C. Water is admitted into these compartments through the valves e, whose
rods or spindles e¹ extend to the surface of the deck and are opened and closed
ly a key, wrench, or other suitable instrument wbich fits all the spindles.
Sluice valves or other convenient means are provided between the com-
partments, and these valves are also opened and closed by means of suitable
rods or levers extending to the surface of the deck. By means of these sluice
valves the communication between each or all of the compartments and the
pump chamber i is opened or closed at pleasure, and the water can thereby
be confined to the after compartments d to balance the weight of the vessel
being lifted, or allowed to flow equally all through the caisson. The pump
chamber or central compartment i and compartments & must be made.water-
tight, but the compartments & need not be so constructed. When the
caissons are constructed of iron I make the central compartment of such a
capacity as to keep the caisson from sinking below the deck when the other
compartments are filled with water. The sides of the said central compartment
must in all cases be made of sufficient strength to resist the inward pressure.
The pulleys over which the main or lifting chains k pass are supported to
turn freely in strong iron brackets 1, which are firmly secured to the deck of
the caisson and are strengthened by the diagonal tie rods m, whose lower ends
are secured in shoes m² or other suitable means of attachment to the bottom
of the girders or other part of the caisson. The lifting chaius k are passed
through holes in the brackets 1, and may be secured and held in any
desired position by means of clamps bolted to one of the links behind the
said brackets. These chains are attached to strong running blocks or
sheaves n which are connected to the ropes or chaius o. The latter are

page_text: passed over suitable guide pullies p and through the fixed blocks p¹ to the
barrel q
of the winding machinery which is preferably arranged in the centre
of the caisson, as shown in Figure 1. The engines for operating the said
winding machinery are supplied with steam from a boiler r, and both engine
and boiler may be of any convenient form or construction. A centrifugal or
other suitable pump s is secured upon strong timbers s' in the pump chamber
i, and is preferably driven by means of a belt s² from the fly wheel q'. When
a vessel of less than a thousand tons weight is to be raised the four caissons
are moored above the same in the positions represented in Figures 4 and 5.
The chains which have been previously placed below the keel of the vessel
A' are now made fast to the running blocks n; water is then admitted through
the valves e into the after compartments d of each caisson or forced into the
same by the pumps through the pipe s³, and the winding machinery on all
four caissons being set in motion the ropes or chains are wound upon the
barrel . The four chains are thus drawn over the pulleys j, the vessel
being supported and lifted thereby, as represented in Figure 5. The quantity
of water in the compartments & can meanwhile be regulated by means of the
valves e and g, the former admitting the water into the compartments & and
the latter allowing it to escape therefrom through the compartments d¹ and d
or direct into the space beneath the pump chamber, whence it can be quickly
expelled by the pumps through the pipe s' In case any of the chains or
ropes should break or if an accident should occur to any part of the lifting
machinery while the sunken vessel is being raised the valves gare immediately
opened to their full extent, allowing the water to flow through all parts of
the caisson and equalise the weight of the same. The four caissons are
moored above the vessel to be raised by anchors attached to the cables B and
are connected together by the ropes C passed around the upright posts D.
For very light or small vessels only two caissons need be used.
In lifting a
vessel of a greater weight than a thousand tons I adopt the following method:-
The lifting chains k being properly placed under the vessels keel as before
described the caissons are towed into the proper position and moored above
the said vessel; water is then admitted through the valves e into all the
compartments d, d', d³, till the four caissons are submerged to within a few
inches of the deck; the chains k are then made taut and attached to the
running blocks n, the said chains are further secured by means of the
clamps or by other suitable means; the water is then pumped out of the
compartments d', d², and the caissons will rise with the sunken vessel hanging
in the chains k; the said caissons and vessel are now towed into shallow
water till the vessel's keel touches the bottom when the caissons are again

page_text: submerged as before; the chains k. being a second time properly adjusted
and secured, and the buoyancy of the caissons restored by expelling the water
from the compartments d', d, the said caissons again rise with the sunken
vessel in the chains. These operations are repeated until the vessel's leck
is above water. When the vessel is raised above water by either of the methods
described the holes or leaks in the same are stopped by divers, and a hose t³ is
attached to the flange t¹ of the pipe t on each caisson and introduced into the
vessel, which is then quickly emptied by means of the pump s. When the said
hose is not attached the pipe is closed by a blank flange. The pointed curved
rod, Figures 6 and 6*, is preferably formed of a round bar of iron, its front end
or point u being flattened and widened so as to pass properly between the vessel's
keel and the bed in which it rests and to prevent the turning over laterally of
the said rod while being passed under the vessel. When this rod is used a
rope is attached to the eye u', which rope when passed under the keel serves
to introduce the light chains, whereby the chains k are drawn and adjusted
under the said keel. The scraper, Figure 7, for removing the mud or sand
from below the sunken vessel is formed of a flat plate v of wrought iron or
steel, and is provided with rods whereby it is attached to a rope v²; the
latter is connected to a capstan on the vessel ³, as represented in Figure 8.
The diver forces the plate into the mud or sand close to the side of the
sunken ship, and the said plate is then drawn towards the vessels by means
of the capstan, a portion of sand or mud being thus scooped out and removed.
The plate vis then again forced edgewise into the bed, as represented in
Figure 8, and again drawn away, the operation being repeated till a channel
or passage has been formed nearly down to the level of the keel for the
introduction of the pointed bar, which may then be passed under the said keel
in the manner above specified.
Having thus fully described my said Invention, and shown how the same
may be conveniently and advantageously carried into practice, I claim,-
First. Raising sunken vessels in chains suspended from floating caissons A,
substantially as described.
Second. The employment of the trussed girders b in the construction of
such caissons, substantially as and for the purpose set forth.
Third. Balancing the weight of the vessel being raised in the chains k by
admitting water into the after compartments d of the said caissons, sub-
stantially as set forth.
Fourth. The curved pointed bar for introducing and adjusting the chains
under the keel of a sunken vessel, constructed substantially as set forth.

page_text: Fifth. The scraper v for removing the mud or sand from the side of a
sunken vessel, constructed substantially as set forth.
In witness whereof, I, the said John Emery Gowen, have hereunto set
my hand and seal this Thirtieth day of June, in the year of our Lord
One thousand eight hundred and sixty-eight.
JOHN EMERY GOWEN. (L.S.)