IMPROVEMENTS IN FLOATING Docks
Year: 1857

page_text: LETTERS PATENT to Edwin Clark, of No. 20, Great George Street, West-
minster, Civil Engineer, for the Invention of "IMPROVEMENTS IN FLOATING
Docks."
Sealed the 3rd April 1857, and dated the 19th January 1857.
PROVISIONAL SPECIFICATION left by the said Edwin Clark at the
Office of the Commissioners of Patents, with his Petition, on the 19th
January 1857.
I, EDWIN CLARK, of 20, Great George Street, Westminster, Civil Engineer,
do hereby declare the nature of the Invention for "IMPROVEMENTS IN FLOATING
Docks," to be as follows:-
This Invention consists in arranging a floating dock so that it may be sunk
in order to receive the ship, and afterwards, having received the ship, be floated
by pumping the water from the space between the side of the ship and the
interior side of the dock. By allowing the dock thus to rest on the bottom I
am enabled to dispense with the air vessels necessary when the dock is kept
floating while receiving the ship, as heretofore. I construct for this purpose a
pontoon or vessel, consisting of an iron shell bolted to transverse girders or
frames built up of sheet and angle iron, and also to longitudinal ribs, which
connect these transverse frames. This vessel has blocks bolted on its bottom,
on which it rests when sunk, and its sides are higher than the draught of the

page_text: largest ship it is required to dock. When the floating dock is to receive a
ship, it is sunk on a bottom suitably levelled, and where the depth of water is
not so great as the height of its sides a gate which closes its end is now
opened and the ship is floated in; the gate then being closed and the ship
suitably shored, the water is pumped out. If the dock is to be used in a tide-
way it will not be necessary to make its sides so high as the draft of the ship
to be docked, as it may then be sunk in water sufficiently deep to rise over its
sides, provided only that its sides be uncovered for a sufficient time at low
water to allow the dock to be pumped out so as to float it. If the rise and
fall of the tide be large it will not be necessary to provide a gate at the end of
the dock as the ship may be floated over and allowed to settle down into it as
the tide recedes. The dock is furnished with a valve or opening to let the
water run out.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edwin Clark in the Great Seal Patent Office on the 18th
July 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWIN
CLARK, of 20, Great George Street, Westminster, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of January, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twentieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Edwin Clark, Her special licence that I, the said Edwin Clark, my
executors, administrators, and assigns, or such others as I, the said Edwin
Clark, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during tho
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 "IMPROVEMENTS IN FLOATING
Docks," I upon the condition (amongst others) that I, the said Edwin Clark,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and ascer-
tain 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

page_text: within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Edwin Clark, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
thereof, that is to say:-
This Invention consists in arranging a floating dock so that it may be sunk
in order to receive the ship, and afterwards, having received the ship, be floated
by pumping the water from the space between the side of the ship and the
interior side of the dock. By allowing the dock thus to rest on the bottom, I am
enabled to dispense with the air vessels necessary when the deck is kept float-
ing. while receiving the ship, as heretofore. I construct for this purpose a
pontoon or vessel, consisting of an iron shell bolted, to transverse girders, or
frames.built up of sheet and angle iron, and also to longitudinal ribs, which
connect these transverse frames. This vessel has blocks bolted on its bottom,
on which it rests when sunk, and its sides are higher than the draught of the
largest ship it is required to dock. When the .floating dock is to receive a
ship, it is sunk on a bottom suitably levelled, and where, the depth of water is
not so great as the height of its sides a gate which closes at its end is now
opened and the ship is floated in; the gate then being closed and the ship
suitably shored, the water is pumped out. If the dock is to be used in a
tideway it will not be necessary to make its, sides. so high, as the draft of
the ship to be docked, as it may then be sunk in water sufficiently deep to rise
over its sides, provided only that its sides be uncovered for a sufficient time at
low water to allow the dock to be pumped out so as to float it. If the rise
and fall of the tide be large it will not be necessary to provide a gate at the
end of the dock as. the ship may be floated, over and allowed to settle down
into it as the tide recedes. The dock is furnished with a valve or opening to
let the water run out.
And in order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the Drawings hereunto
annexed.
DESCRIPTION OF THE DRAWINGS.
alessation THe is plen and Diu
trans

page_text: top and bottom, so as to form flanges, and connected together sideways by
covering pieces of T-iron 6, 6. In this way sufficient strength is obtained to
support the weight of a ship, the keel bearing at the centre of each of the
girders; at the ends the girders are turned up, so as to form the sides of
the dock, and are strengthened at the back by wooden beams ³, 1³. C, C, C,
are three longitudinal girders or ribs which run from end to end of the dock;
they are constructed in a similar manner to the transverse girders b, which
they connect together. One end of the dock is closed by gates d, d, which
are of the description ordinarily employed in docks. When a ship is to be
docked the floating dock is sunk on a prepared bottom, and it then rests on
the wooden blocks e, e; the gates d, d, are now opened, and the ship is floated
in; the depth of water in which the dock is sunk being such as to admit of
this, but not being sufficient completely to submerge the dock. After the
ship has entered the gates are closed, and the water is pumped out of the
dock until the vessel begins to bear on the girders b; it is then shored by
the shores f,f, which are stepped on to the ledges g, g, running from end to
end of the dock, and bolted to the girders b, b. When the ship is securely
shored the dock is pumped dry, and it then floats with the ship in it. The
floating dock, which is shewn in the Drawing, is adapted to be used in places
where there is no tide, or where the rise and fall of the tide is very small;
but if at the position where the floating dock is to be used the rise and
fall of the tide is considerable, then the height of the sides of the dock may be
much reduced, as they need only be high enough to remain uncovered at low
water for a sufficient time to allow of the water being pumped out of the
dock. When the tide rises and falls to such an extent as to leave the bottom
on which the dock is sunk dry at low water, then I so reduce the height of
the sides of the dock that it becomes identical with the vessel which, in the
Specification of a Patent granted to me, and bearing even date with the
Patent of which this is the Specification, I have called a saucer, and this
vessel I will now proceed to describe. Figure 4 is a side elevation; and
Figure 5 is a half plan thereof, with the beams, planking, and woodwork
removed from one end; Figure 6 is a portion of a longitudinal section;
Figure 7, of a longitudinal elevation; and Figure 8, of a plan of the same.
Figure 9 is an end view, partly in section. The Figures 6, 7, 8, and 9 are
on a larger scale than the Figures 4 and 5.
sheet iron, which is rivetted together, as is shewn by the Drawings; b, b, are
transverse girders, which in this instance are built up of wood bolted together,
and arranged in such a manner that a weight put on the girders has a
a, a, is the external skin of

page_text: tendency to keep the skin a extended; 6, 61, are baulks of timber forming
the upper part of the girders b, and on the centre of each of which the keel
of the vessel rests; c, c, are longitudinal girders or ribs running from end to
end of the saucer; they consist of iron plates rivetted together and to flanges
of L-iron at the top and bottom. These flanges at the bottom are rivetted to
the skin a, and at the top they are bolted to the baulks . .d, d, is the
planking or flooring, which is supported by the longitudinal joists d', d',
resting on the bottom or skin of the saucer. When a ship is to be raised on
to the saucer, it is sunk either in a tideway, as before mentioned, or in an
ordinary graving dock, or on to a raising apparatus, as I have described in
the Specification of a Patent granted to me, and bearing even date with the
Patent of which this is the Specification, and the ship to be raised is floated
over the saucer and shored in a similar manner to that used for shoring ships
on Morton's slip, then as the tide falls or the water is pumped out of the
graving dock, or as the saucer is raised, the water runs out of the saucer
through an orifice which is furnished with a flap valve arranged so as to let
water run out and prevent its running in. On the return of the tide, or
when the water is readmitted to the dock (if a graving dock has been used),
or when the saucer is again lowered (if a raising apparatus has been used),
the saucer will float with the ship, and may be removed to a place suitable
for effecting the required repairs.
Having thus described the nature of my Invention, and the manner of per-
forming the same, I would remark that I am aware that floating docks have
heretofore been constructed, but such floating docks have been arranged with
air vessels or chambers for enclosing air, by means of which these docks can
be kept floating while filled with water, and while receiving the ships to be
docked; I do not, therefore, claim the constructing floating docks in this way;
but by allowing floating docks to rest on the bottom when receiving the ships,
I am enabled to dispense with the air vessels, and when floating docks are
used in a tideway, or with a graving dock, or with a raising apparatus, I
am also enabled thereby very greatly to reduce the heighth of their sides,
which in the docks heretofore constructed have necessarily been greater than
the draught of the largest ship to be docked; what I do then claim is,
the constructing floating docks, by which I mean vessels arranged suitably
for receiving ships into or on to them, and of floating with such ships in or on
them without air vessels, to keep them floating when filled with water.
I also claim the constructing floating docks with transverse girders or frames
connected together by longitudinal ribs, as herein described. I also claim the

page_text: constructing floating docks with sides less in heighth than the draught of the
largest ships which they are constructed to dock. I also claim the constructing
floating docks without gates.
In witness whereof, I, the said Edwin Clark, have hereunto set my
hand and seal, this Sixteenth day of July, in the year of our Lord 5
One thousand eight hundred and fifty-seven.
EDWIN CLARK. (L.S.)

page_text: Half plan of saucer
showing skin.
FIG. 5.
Half plan of saucer.