IMPROVEMENTS IN THE CONSTRUCTION OF FLOATING Docks
Year: 1859

page_text: LETTERS PATENT to John Pile, of West Hartlepool, in the County of
Durham, Ship Builder, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF FLOATING Docks."
Sealed the 31st May 1859, and dated the 1st March 1859.
PROVISIONAL SPECIFICATION left by the said John Pile at the Office
of the Commissioners of Patents, with his Petition, on the 1st March
1859.
I, JOHN PILE, of West Hartlepool, in the County of Durham, Ship Builder,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF FLOATING Docks," to be as follows:-
This Invention relates to a peculiar construction and arrangement of
apparatus for facilitating the raising of vessels for repair or examination, and
consists in the application and use of two sets of pontoons, the one set being
kept constantly floated upon the surface of the water, and the other set being
alternately submerged and floated for the purpose of sinking beneath the
bottom of the ship, and of then rising and lifting the ship up with it, the water
for such purpose being pumped out of the submerged pontoon by rotatory.
pumps or other water elevating apparatus. The first set of pontoons serves as
a means of steadying the ship and second pontoon when elevated, by reason of
the edges of the elevating pontoon bearing against the under side of the floating
pontoons. The floating pontoons are guided over the elevating pontoon by
suitable uprights passing through suitable apertures made in the floating.
pontoons, and connected with the latter elevating pontoon. Chain and.

page_text: winches, carried on the floating pontoon and connected with the elevating
pontoon, serve to prevent its immersion to an unnecessary depth, whilst during
its elevation the slack is duly taken in. The dead weight of the elevating
pontoon is partially neutralized by having air-tight spaces attached thereto, so
that it may be more easily supported by the chains before referred to.
In some cases a third pontoon may be used upon which the ship is floated
away for repairs.
•
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Pile. in the Great Seal Patent Office on the 1st
September 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
PILE, of West Hartlepool, in the County of Durham, Ship Builder, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Pile, Her special license that I, the said John Pile,
my executors, administrators, and assigns, or such others as I, the
said John Pile, my executors, administrators, or assigns, should at any
time agree with, and 'no others, from time to time and at all times there-
after 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 "IMPROVE-
MENTS IN. THE-CONSTRUCTION, OF FLOATING DOCKS," upon the condition (amongst:
others) that I, the said John Pile; by. an instrument in writing, under: my-
hand and seal, should particularly describe and ascertain 'the nature of the said:
Invention, and in what manner the same was to be performed; .and
cause the sanie to be filed in the Great Seal' Patent Office within six:
calendar months next and immediately aftér: the date of the said Letters
Patent.
NOW KNOW YE, that I, the; said: John Pile, do hereby declare the
nature of my 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, and to the 8
letters and figures marked thereon; that is to say::

page_text: My said Invention relates to à peculiar construction and arrangement of
apparatus for facilitating the raising of vessels for repair or examination, and
consists in the application and use of two sets of pontoons, the one set being
kept constantly floated upon the surface of the water, and the other set being
alternately submerged and floated for the purpose of sinking beneath the
bottom of the ship, and of then rising and lifting the ship up with it, the water
for such purpose being pumped out of the submerged pontoon by rotatory
pumps or other water elevating apparatus. The first set of pontoons serves as
a means of steadying the ship and second pontoon when elevated by reason of
the edges of the elevating pontoon bearing against the under side of the floating
pontoons. The floating pontoons are guided over the elevating pontoon by
suitable uprights, passing through suitable apertures made in the floating
pontoons, and connected with the latter or elevating pontoon chains and
winches carried on the floating pontoons, and connected with the elevating
pontoon, serve to prevent its immersion to an unnecessary depth, whilst during
its elevation the slack is duly taken in. The dead weight of the elevating
pontoon is partially neutralized by having air-tight spaces attached thereto, so
that it may be more easily supported by the chains before referred to.
In some cases a third pontoon may be used, upon which the ship is floated
away for repairs.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several Figures on the explanatory Sheet of
Drawings, which I have hereunto appended for the purpose of shewing.certain
modifications under which my improvements may be judiciously carried out in
practice, that is to say: Figure 1 on the accompanying Sheet of Drawings is a
longitudinal elevation or side view, showing one modification of my improveil
floating dock; Figure 2 is a front elevation of the dock entrance; Figure 3.
is an end view of a floating pontoon, having a vessel supported thereon; and
Figure 4 is a plan corresponding to Figure 1. According to the arrangement
delineated in the accompanying Drawings, my improved floating dock consists
of a series of columns A, arranged at equal distances asunder in two parallel
lines; the space between these lines of columns forming the area of the dock:
The columns A are by preference hollow pillars of cast. or wrought iron, the
lower extremities of which are firmly fixed to the bottom pontoon or lift, and
act as air tubes to admit the air into the pontoon, or lift as the water. is
pumped out, these pillars or columns rising and falling with the pontoon. On
the upper extremities of the columns A is built a gangway or platform B,
which is carried completely round the dock, as shown in the plan, Figure 4,
illustrative Drawing. The inner end of tlie gangway opens out into a
on my
'

page_text: roadway at C, to afford access thereto. The opposite or outer end of the
gangway at D forms a swing bridge, to admit of the entrance of vessels when
the bridge is swung open or drawn aside. A hand rail E is carried round the
gangway B to provide for the safety of those traversing to and fro. The
columns A serve also as guides for the floating pontoon F, which extends
from end to end and from side to side of the dock, and is constructed of wood
or sheet iron, riveted and caulked, so as to make it water tight. A series of
tubular apertures, corresponding to the number of the columns A, are made
in a vertical direction through the pontoon; these tubular openings encircle
the columns A, and they are made sufficiently large to admit of the pontoon
easily rising and falling with the tide. The pontoon forms a platform extend-
ing outwards beyond the stern of the ship, and at the inner end it converges
like the bows of a vessel, the area between the inner sides of the pontoon
affording ample space for the admission of the vessel. The upper surface of
the pontoon F forms a stage or platform for the shipwrights to work upon,
and a handrail G is carried round the pontoon to protect the men from accident
on the outer side. The outer end H of the pontoon is formed in two parts,
and these are made to swing back when required by means of a circular rack,
fitted round the parts on which the swinging ends are centred and actuated by
a pinion fitted on the lower end of a vertical shaft, which may be wrought
by a winch handle or other convenient means. In lieu of this arrangement
the ends of the pontoon may be caused to move laterally by means of a
rack and pinion or other equivalent mechanical contrivance. The floating
pontoon F has pendant from its lower side a series chains I, the lower ends
of which are secured to the submerged pontoon J, by means of which chains
the submersion of the pontoon or lift J is regulated to any depth. This
elevating pontoon J is constructed of wood or sheet iron, and carefully caulked,
so as to be thoroughly water tight; it carries the columns A, which are
securely fixed thereon. The elevating pontoon J is so arranged that it may be
partially filled with water, so as to give it a greater specific gravity than the
surrounding fluid, in order that may be submerged with facility; upon
discharging this water from the pontoon sufficient buoyant power is imparted
to it to lift a vessel out of the water. The depth to which the pontoon J is
to be sunk prior to floating a ship thereon is regulated by means of the
chains I, which are wrought either by means of windlasses, or a shaft extending
along each side of the dock, and having winding drums fitted thereon opposite
to the several chains, the longitudinal shafts being primarily actuated by a
steam engine. These hollow columns A may either form the suction pipes of
the pumps, or separate suction pipes may be placed therein as desired, the

page_text: 'pumps being worked by a steam engine arranged in the engine house K. By
this means, when the buoyant power of the pontoon J is required for the
purpose of raising a vessel out of the water, air is pumped into the pontoon,
or the water pumped out, thus obtaining the full effect of its buoyant force.
In addition to the pontoon J there is a secondary pontoon L, which is con-
structed so as to be easily attached to it; this pontoon is made to any required
size, according to the weight of the vessel to be lifted, and is attached to the
pontoon J. Upon this secondary pontoon L the cradle M and chock blocks N
for preventing the ship from heeling over are arranged. Prior to the vessel
being docked for examination or repair, the pontoon L is secured to the lower
pontoon J, as shown in the end view, Figure 2 of the accompanying Drawings.
The vessel is then floated into the dock, and the pontoon J is raised by
pumping air into or water out of the interior thereof, the vessel being kept
meanwhile equidistantly from the columns A; when the pontoon L touches
the keel of the vessel, the blocks N are brought beneath the hull, in order to
keep the ship in an upright position. The blocks N are drawn down the
inclined surface of the cradle by means of the chains O, which are carried
away below the cradle, and away to windlasses fitted for the purpose on the
platform of the pontoon F. The bow and stern of the ship is further steadied
and supported by means of the shores P, which are jointed to the pontoon L,
so that they may be readily thrown back out of the way when it is desired to
release the vessel. When the ship is floated over the cradle M and rests upon
the blocks N, the shores P are brought up against the bow and stern of the
vessel by the chains Q, which may be actuated in manner similar to the
chains O; or the chains may be made fast to eyes screwed into the cradle M,
the slack of the several chains being taken up on spindles actuated by means
of the winch handles R. When it is desired to remove the ship from the
dock, the pontoon L is cast off from the pontoon F, and she is floated out
thereon, as shewn in Figure 3 of the illustrative Drawings. To float the ship
from off the pontoon L after repairs, the pontoon and ship are again brought
into the dock, and placed over the elevating pontoon J. Water is then let
into both pontoons J and L, and they sink accordingly, leaving the ship
floating on the surface. The elevation, Figure 3, shows the ship floating upon
the pontoon L, and free from the dock. With these arrangements of floating
docks, ships may be examined or repaired with greater facility and ease than
by any other principle now in existence. Neither foundation, masonry, nor
fixed posisition is requisite; it can be floated anywhere and to dock or ship
requires neither rise nor fall of the tide; the lift can be worked either in docks
or rivers, where there is sufficient water. The pontoons are so constructed

page_text: that when requiring repairs they can raise each other out of the water for that
purpose, without nioving from the place where the work is generally carried
on, with the greatest ease. These pontoons or docks may also be used for
lifting ships in the present graving docks, now built of stone or otherwise, by
being put into the graying dock, the water pumped out of the dock, and the
pontoon allowed to rest on the bottom. The pontoon is then filled with water
and the dock also filled, when a ship may be introduced; the water is then
pumped out of the dock till the ship rests upon the pontoon. In order to
undock the ship, the water is run out of the pontoon, the sluices of the dock
shut, water let into the dock, and the pontoon with the vessel upon it rises and
may be floated out.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent, is→
First, the general arrangement and construction of buoyant or floating
docks for the repair and examination of ships or vessels, as herein-before
described and shewn on the accompanying Drawings.
Second, the system or mode of arranging and constructing floating docks,
in which the vessel is raised up out of the water by means of a floating
pontoon or pontoons, which may be floated or submerged at pleasure, as
herein-before described and shewn in the accompanying Drawings.
Third, the system or mode of regulating the specific gravity of the elevating
pontoon or pontoons, by means of water admitted thereto, and of removing
or displacing the same by a lift pump, or by means of air pumped into the
pontoon or pontoons, as herein-before described.
In witness whereof, I, the said John Pile, have hereunto set my hand
and seal, this First day of September, in the year of our Lord One
'thousand eight hundred and fifty-nine.