IMPROVEMENTS IN THE CONSTRUCTION AND APPLICATION TO USE OF PONTOONS, ALSO APPLICABLE TO CAMELS AND FLOATING DOCKS
Year: 1871

page_text: LETTERS PATENT to Robert Turnbull, of Number 4, Knapp Road,
Bromley-by-Bow, in the County of Middlesex, Naval Architect, for
the Invention of "IMPROVEMENTS IN THE CONSTRUCTION AND APPLICATION
TO USE OF PONTOONS, ALSO APPLICABLE TO CAMELS AND FLOATING DOCKS."
Sealed the 15th April 1871, and dated the 21st January 1871.
PROVISIONAL SPECIFICATION left by the said Robert Turnbull at the
Office of the Commissioners of Patents, with his Petition, on the
21st January 1871.
I, ROBERT TURNBULL, of Number 4, Knapp Road, Bromley-by-Bow,
in the County of Middlesex, Naval Architect, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE CONSTRUCTION AND
APPLICATION TO USE OF PONTOONS, ALSO APPLICABLE TO CAMELS AND FLOATING
Docks," to be as follows:-
My Invention relates to the construction of pontoons for raising ships
or vessels out of the water for survy or repair or any other purpose, and
to their application to use in locks between different water levels, whereby
I obtain a cheap lifting power..

page_text: It consists in constructing each pontoon with a keel or keels along or
across its bottom, the keel or keels being of sufficient depth to keep the
bottom of the hollow part (or bottom proper) of the pontoon on a level
with or above the low water line or sill of the lock when the keel or
keels rests or rest on the bottom of the lock. The keel or keels should
be made adjustable to meet variations of the low water level of the lock,
and for the further purpose herein-after referred to of adding stability to
the pontoon when required. The pontoon is also furnished with valves
or openings whereby ingress and egress of water to and from its interior
may be allowed and controlled or stopped.
The pontoon is applied to use in the following manner :-The lock
being full the pontoon is floated, towed, or hauled into it and may be
sunk therein by the admission of water to its interior, but I prefer to
close the inner gates of the lock or those nearest to the high level water
and their sluice or sluices and to open the sluice or sluices of the outer
gates to permit the pontoon to sink or fall as the water leaves the lock.
When the pontoon has grounded the sluice or sluices of the outer gates
is or are closed and the valves or openings of the pontoon opened. The
sluice or sluices of the inner gates is or are then opened and the entering
water fills both the lock and the interior of the pontoon which remains
aground on the bottom. The inner gates are then opened and the ship
or vessel to be raised is floated over the pontoon. The inner gates and
their sluice or sluices are then closed and the sluice or sluices of the
outer gates opened. As the water leaving the lock deposits the ship or
vessel on the pontoon she is secured in position while the valves or
openings being open the water escapes from the interior of the pontoon
by its own gravity. The lock having been emptied of water to its low
water level or sill the sluice or sluices of the outer gates is or are shut,
the valves or openings of the pontoon are closed, and the sluice or sluices
of the inner gates opened, when the water entering the lock till it reaches
the high water level floats the pontoon which with its burthen may on
the opening of the inner gates be hauled or towed to any desired part of
the high level water.
When a great degree of stability of the pontoon is desired, as in the
case of its use as a dry dock for extensive repairs of the ship or vessel it
carries or supports, it should be berthed in shallow water and the
adjustable keel or keels should be forced or let down to the bottom and
retained thereon.

page_text: The ship or vessel may be removed from the pontoon by reversing the
herein-before described process.
The ship or vessel may be removed from the pontoon by reversing the
herein-before described process.
This Invention is also applicable to camels and floating docks.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Turnbull in the Great Seal Patent Office on
the 21st July 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
TURNBULL, of Number 4, Knapp Road,, Bromley-by-Bow, in the County
of Middlesex, Naval Architect, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of January, in the year
of our Lord One thousand eight hundred and seventy-onc, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Turnbull, Her special
licence, that I, the said Robert Turnbull, my executors, administrators,
and assigns, or such others as I, the said Robert Turnbull, my exccutors,
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, excrcise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE CON-
STRUCTION AND APPLICATION TO USE OF PONTOONS, ALSO APPLICABLE TO CAMELS AND
FLOATING DOCKS," upon the condition (amongst others) that I, the said
Robert Turnbull, 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 Robert Turnbull, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawings hereunto

page_text: say):-
My Invention relates to the construction of pontoons for raising ships
or vessels out of the water for survey or repair or any other purpose, and
to their application to use in locks between different. water levels
whereby I obtain a cheap lifting power.
1
'
It consists in constructing each pontoon with a keel or keels. along or
across its bottom, the keel or keels being of sufficient depth to keep the
bottom of the hollow part (or bottom proper) of the pontoon on a level
with or above the low water line or sill of the lock when the keel or
keels rests or rest on the bottom of the lock. The keel or keels should
be made adjustable to meet variations of the low water level of the
lock and for the further purpose herein-after referred to of adding
stability to the pontoon when required. The pontoon is also furnished
with valves or openings whereby ingress and egress of water to and from
its interior may be allowed and controlled or stopped.
The pontoon is applied to use in the following manner:-The lock
being full the pontoon is floated, towed, or hauled into it, and may be
sunk therein by the admission of water to its interior, but I prefer to
close the inner gates of the lock or those nearest to the high level water
and their sluice or sluices and to open the sluice or sluices of the outer
gates to permit the pontoon to sink or fall as the water leaves the lock.
When the pontoon has grounded the sluice or sluices of the outer gates
is or are closed and the valves or openings of the pontoon opened. The
sluice or sluices of the inner gates is or are then opened and the entering
water fills both the lock and the interior of the pontoon which remains
aground on the bottom. The inner gates are then opened and the ship
or vessel to be raised is floated over the pontoon. The inner gates and
their sluice or sluices are then closed and the sluice or sluices of the
outer gates opened. As the water leaving the lock deposits the ship or
vessel on the pontoon she is secured in position while the valves or
openings being open the water escapes from the interior of the pontoon
by its own gravity. The lock having been emptied of water to its low
water level or sill the sluice or sluices of the outer gates is or are shut,
the valves or openings. of the pontoon are closed, and the sluice or sluices
of the inner gates opened when the water entering the lock till it reaches
the high water level floats the pontoon which with its burthen may on

page_text: impos. on one Construction and application of Lontoons.
the opening of the inner gates be hauled or towed to any desired part of
the high level water.
When a great degree of stability of the pontoon is desired, as in the
case of its use as a dry dock for extensive repairs of the ship or vessel
it carries or supports, it should be berthed in shallow water and the
adjustable keel or keel should be forced or let down to the bottom and
retained thercon.
This Invention is also applicable to camels and floating docks.
The ship or vessel may be removed from the pontoon by reversing the
herein-before described process.
Having thus stated the nature of the said Invention, I will proceed to
describe more particularly in what manner the same is to be performed
by the aid of the accompanying Drawings in which the same letters of
reference indicate corresponding parts throughout.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents a longitudinal vertical section of the fore and
after ends of the pontoon with a vessel thereon. A, A, are the ends
of the pontoon, and B, B, the bottom proper; C, C, is a longitudinal
keel which I prefer to make of iron and after the manner of a girder,
and such keels are herein-after called main keels to distinguished them
from the adjustable keels. To the bottom of the main keels I prefer to
attach a beam or cushion of wood D, D, to prevent the iron from coming
into contact with the brickwork or masonry of the lock.
Figure 2 is a plan of the same showing the valves, cach of which is
marked K.
Figure 3 is a midship half section of the pontoon with adjustable
keels E, E, hove down to support the bottom proper at or above the
low water level of the lock; F is a wire rope running fore and aft; G‘is
a fall and blocks bearing the adjustable keel and made fast to the rope F;
I is a cross girder to keep the keels in position and prevent them from
canting or buckling.
Figure 4 is same as Figure 3 but with adjustable keels hove up and
main keels resting on the bottom of the lock; Figure 5 is a short
longitudinal vertical section from amidships shewing the construction
of the main keels; Figure 6 is a longitudinal vertical section of an end
of the pontoon with a purchase H for lowering and raising the adjustable

page_text: kecl which is made of wood and owes its adjustability to being con-
structed on the sliding chock or wedge principle as shewn.. Each end
of the pontoon should be furnished with a purchase similar to those in
ordinary use in heaving up slips so that as the chocks on the starboard
side move aft the chocks on the port side may move forward. The
position of the keel when lowered is indicated by the dotted lines.
Figure 7 shows end view of the laden pontoon resting on. the main
kccls, the water line L of the lock being at its lowest ; Figure 8 shows
the same pontoon afloat with the water in the lock at its high level;
Figure 9 shows the same pontoon supported on the adjustable keels to
suit a water line not as low as that in Figure 7; Figure 10 shews the
same pontoon again afloat with adjustable keels hove up.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I would remark that I do not claim
as of my Invention the parts represented and described otherwise than
as herein-after stated, but what I do claim as of my Invention is,―
First. The construction of the pontoon as herein-before described so
as to adapt it to use in locks between different water levels for the
purposes herein-before described.
Secondly. The use of the pontoon in locks between different water
levels substantially in the manner and for the purposes herein-before
described.
Thirdly, and lastly. The use of adjustable keels substantially in the
manner and for the purposes herein-before described.
In witness whereof, I, the said Robert Turnbull, have hereunto set
my hand and seal, the Twenty-first day of July, in the year of
our Lord One thousand eight hundred and seventy-one.
· ROBERT TURNBULL. (L.S.)
Witness,
W. B. ARNOLD,
53, Gracechurch Street, City.