IMPROVEMENTS IN FLOATING DOCKS AND PONTOONS
Year: 1878

page_text: LETTERS PATENT to Josiah Latimer Clark and John Standfield, both of
6, Westminster Chambers, Victoria Street, in the City of Westminster, for
the Invention of "IMPROVEMENTS IN FLOATING DOCKS AND PONTOONS."
PROVISIONAL SPECIFICATION left by the said Josiah Latimer Clark and
John Standfield at the Office of the Commissioners of Patents on the 9th
February 1878.
JOSIAH LATIMER CLARK and JOHN STANDFIELD, both of 6, Westminster
Chambers, Victoria Street, in the City of Westminster. "IMPROVEMENTS IN
FLOATING DOCKS AND PONTOONS."
This Invention has for its object improvements in floating docks and pontoons.
The improvements consist. principally, in so constructing a dock that the sides or
portions of the sides of the dock are attached to the body or remaining portion of
the dock by vertical grroves or slides, so that these portions can be raised or
lowered independently. The vessel is first raised by the dock in its normal or
Ushaped form as high as the power of the dock will admit; the sides or portions
of the sides are then allowed to descend by means of the slides until they are
nearly submerged, so that the end elevation of the dock resembles the letter H,
and being keyed or secured in their new position, the water is then pumped out of
them and their lifting power raises the vessel to its full height. It will be seen
by this arrangement that when a vessel is docked, instead of the sides of the dock
being uselessly raised high out of the water, and having to be supported by the
body of the dock, the greater portion of their lifting power is brought into action,
and the effective power of the dock is thereby fully doubled.
It is preferable that a certain portion of the sides should be fixed to the body of
the dock and contain the engines and pumps. Supposing the four corners of the
dock to be fixed, then there will be two intermediate portions sliding in vertical

page_text: grooves, one on each side. The dock when fully lowered would have the ordinary
☐ form of section; on pumping the water out of the dock the bottom or body with
its four corner elevations would rise, the stability of the whole system being due to
the unsubmerged displacement of the four corners and the vessel itself; the two sides
being detached remain down at their lowest level. When all the lifting power of
the bottom of the dock has been developed the two side portions are pinned or
otherwise secured and pumped dry, adding their buoyancy to that of the dock.
In some cases we prefer that the two central portions of the side of the dock
should be fixed and contain the engines and pumps, in this case there will be four
independent sliding portions, one at each corner, which may be raised or lowered in
pairs alternately as desired.
In order to guide the sliding portions of the dock we not only utilize the fixed
portions to form slides, but also erect frames along the side, which also serve as
side shoring frames for supporting the vessel within the dock.
It will be seen that if the dock be pumped dry and the sliding portions keyed at
their highest level, that they will be supported entirely, out of the water and con-
veniently situated for repairing and painting; and on the other hand, if the sliding
portions be keyed at their lowest level, and are properly proportioned, they will
when pumped dry entirely raise, the body, of the dock clear of the water, and thus
enable every portion to become easily accessible for cleaning and repair, the whole
is thus made perfectly self docking.
In some cases we prefer, instead of allowing the sliding sides to sink in the water,
to force them down beneath the water by hydraulic pressure, so as to utilize
the full buoyancy of the sliding side portions in addition to that of the body of
.the dock.
It is obvious that, floating pontoons of every description can be built in sections
and provided with slides, and means of securing them at different levels as above
described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Josiah Latimer Clark and John Standfield in the Great Seal Patent
Office on the 9th August 1878.
JOSIAH LATIMER CLARK and JOHN STANDFIELD, both of 6, Westminster
Chambers, Victoria Street, in the City of Westminster. "IMPROVEMENTS IN
FLOATING DOCKS AND PONTOONS."
This Invention has for its object improvements in floating docks and pontoons.
For this purpose we construct them in separate parts or compartments, which are
connected with each other by vertical slides or grooves, so that they can be raised
or lowered independently.
For a floating dock for docking vessels we thus attach the sides or portions of
the sides of the dock to the body of the dock, so that these portions can be raised
or lowered independently. The vessel is first raised upon the body of the floating
dock in the usual manner as high as the power will admit of; the sides of the dock
are then lowered by means of the slides until they are nearly submerged, or they
may have been allowed to remain at this level from the first, and in this position
they are keyed fast to the body of the dock. The water is then pumped out from
the sides, so that their lifting power being added to that of the body, the vessel is
raised to its full height. By this arrangement when the vessel is docked, the sides,
instead of being supported uselessly in the air, are partially submerged, and they
increase by so much the lifting power of the dock without increasing its weight or
cost.
A second advantage is that the body of the dock is competent to raise the sides.
at any time completely out of the water for cleaning and painting; and in like
manner the sides when keyed at their lowest level are competent to raise the body
of the dock out of the water, so that the dock is self docking, and the whole is
perfectly accessible for painting and repairs.
It is obvious that the same result can be obtained without the use of slides by
having the sliding portions of the dock quite detached and independent, and
merely bolted or otherwise secured at the different levels; their operation would
be the same, but their use would be far less convenient.
In some cases also the buoyant sides or parts can, as herein-after described, be
made to turn down on hinges."
A floating dock or pontoon formed with two sets of moveable buoyant chambers,
as above described, can likewise be used to lift a vessel or other object by pumping
out water from one set of chambers, then lowering the other portion or portions,
and in turn bringing their buoyancy into play; in this manner they can each lift
alternately, and if the ship or other object to be lifted be suspended by chains it
can by alternately lifting and shortening the chains be brought to the surface.
Figure 1 represents an end elevation of a dock sunk to its lowest level and ready
to receive a vessel upon it. It has the ordinary form of section, as in other
floating docks. In this Drawing, and in all the others, the sliding portions of the
dock are marked A, A, and the body of the dock is marked C, C. The fixed.
portion of the sides is not visible in this elevation.
In Figure 2 the sliding sides marked A; A, are shown lowered, and a part of the
fixed portion marked B becomes visible; Figure 3 gives a side elevation of the
dock in this position, C being the body; B, the fixed part of the sides; and A, A,'
the sliding sides.
Figure shows the dock ready to receive a vessel.
In Figure 2 the vessel is supposed to have been raised as high as possible by
pumping out water from B and C; the four corner sliding portions A, A, are then
supposed to have been allowed to slide down, to have been keyed in this lowest
position, and then to have had the water pumped out of them, so as to give the
greatest possible lifting power to the dock; Figure 3 is a side elevation of
Figure 2; and Figure 4 is a plan of the same.

page_text: In all positions the stability of the dock is amply secured by the fixed portions
of the sides, which remain always above water.
In the remaining Figures the arrangement is somewhat different; instead of there
being two fixed portions at the sides and four sliding portions there are four fixed
portions at the corners and only two sliding portions.
Figure 16 shows this arrangement in plan; B, B, B, B, being the fixed portions,
and A, A, the sliding; and Figure 15 shews the same in side elevation, sunk ready
to receive a vessel.
Figures 5 and 6 show the same arrangement when the sliding sides are lowered
so as to develop the greatest lifting power, a vessel being shown upon the dock in
Figure 5.
In all cases there are engines and pumps in the fixed portions of the sides, and
generally there are also engines and pumps in the sliding portions, as in Figures 5,
7, and 9, though in some cases it may be advisable to pump these dry by flexible
hose from the fixed engines.
When the water in which the dock has to float is very shallow we sometimes
prefer, as before mentioned, to let the sides turn down on hinges instead of sliding
down in grooves. By this construction the dock is able to float in very shallow
water, and it may be used for lifting vessels over bars, or into rivers and creeks,
where there is not much depth of water.
Figures 11, 12, 13, and 14 show this construction; Figure 14 is an end elevation,
showing the dock lowered ready to receive a vessel, the sides being in the ordinary
position; Figure 11 is an end elevation, the sides being turned down on the hinges
or centres D, D, in the direction shown by the dotted lines E, E, until they rest in
the new position A¹, A', or in some intermediate position, when they are securely
keyed or blocked. Figure 12 shows the same in side elevation with the sides
lowered, so as to display the side shoring frames J; and Figure 13 gives a plan of
the same.
On pumping out the water from the body of the dock C, C, it rises, and the
sides A, A, gradually fall outwards, turning upon their hinges; when the whole of
the water has been pumped out of the body the sides A, A, are allowed to fill with
water and to sink into the position shown in Figure 11. When in this position
they are secured by the struts shown at H, H, or by other means, and the water is
then pumped out of them, and the full elevation of the dock is thus obtained; the
whole buoyancy of the sides is thus brought into play. The struts H, H, may be
provided with pawls locking into ratchets on the side shoring frames J, J, or vice
versa, so that as the sides descend they are continually held in their new position.
Figures 7, 8, 9, and 10, show the arrangement by which the dock is made perfectly
self docking. Figure 7. shows an elevation, in which the sides are lowered and
then pumped dry, their buoyancy is then such that the body of the dock C, C, and
the fixed corners B, B, are thereby raised completely out of the water, so that a.
boat or raft can pass under the dock for the purposes of cleaning and painting;
Figure 8 shows the same arrangement in end elevation. In Figure 9 the position-
is reversed; the body of the dock is now floating, and the sides A, A, A, A, are
lifted completely out of the water, so as to be accessible beneath. Figure 10 gives
the same in end elevation.
J, J, J, in Figures 1, 2, 8, 10, &c., represent the side shoring frames, which serve
for shoring the ship and for carrying the slides which guide the sides in their
descent; they are pierced with holes at uniform distances for inserting the pins
which fix the sides in their several positions.
When the dock is employed for raising sunken vessels the chains are attached
first to the body of the dock and a lift taken, and then other chains attached to
the sides and a second lift taken, the body being again lowered and the operation
repeated; and so by alternate lifts the vessel is raised to the surface, or nearly so.
It will be seen in all the foregoing arrangements that when a vessel is docked,
instead of the sides of the dock being uselessly raised high out of the water, and
having to be supported by the body of the dock, the greater portion of their lifting

page_text: power is brought into action, and the effective power of the dock is by this means
at least double.
Having thus described the nature of our Invention, and the manner of performing
the same, we would have it understood that we claim,-
First. Constructing a floating dock or pontoon in separate compartments or
parts, which are connected with each other by vertical grooves or slides, or other
means, so that one part or parts can be lowered independently of the other part
or parts by admitting water to them, and can then be secured and the water
pumped out from them, so as to add their lifting power to that of the other parts of
the dock or to dock them for repairs.
Second. Constructing a floating dock, as herein described, with the buoyant sides
or portions of the sides attached to the body of the dock by vertical grooves or
slides, or by hinges or bolts, so that these portions can be independently raised or
lowered by admitting water to or pumping it out from them.
Third. Constructing a floating dock with a body C, fixed buoyant portions of
sides B, and sliding bolted or hinged buoyant portions A, as herein described.
In witness whereof, we, the said Josiah Latimer Clark and John Standfield,
have hereunto set our hands and seals, this Seventh day of August, in
the year of our Lord One thousand eight hundred and seventy-eight.