IMPROVEMENTS IN MACHINERY, APPARATUS, AND WORKS OF CONSTRUCTION, INTENDED TO BE EMPLOYED AND THE MODE OR METHOD OF USING OR EMPLOYING THE SAME FOR THE PURPOSE OF EXAMINING OR REPAIRING SHIPS AND OTHER VESSELS
Year: 1860

page_text: LETTERS PATENT to George Banks Rennie, of the Firm of George
Reanic & Sons, Holland Street, Blackfriars, Civil Engineer, for the
Invention of "IMPROVEMENTS IN MACHINERY, APPARATUS, AND WORKS OF
CONSTRUCTION, INTENDED TO BE EMPLOYED AND THE MODE OR METHOD OF USING
OR EMPLOYING THE SAME FOR THE PURPOSE OF EXAMINING OR REPAIRING SHIPS
AND OTHER VESSELS."
Invention of "IMPROVEMENTS IN MACHINERY, APPARATUS, AND WORKS OF
CONSTRUCTION, INTENDED TO BE EMPLOYED AND THE MODE OR METHOD OF USING
OR EMPLOYING THE SAME FOR THE PURPOSE OF EXAMINING OR REPAIRING SHIPS
AND OTHER VESSELS."
Sealed the 18th June 1861, and dated the 20th December 1860.
PROVISIONAL SPECIFICATION left by the said George Banks Rennie at
the Office of the Commissioners of Patents, with his Petition, on the
20th December 1860.
I, GEORGE BANKS RENNIE, of the Firm of George Rennie & Sons, Holland.
Street, Blackfriars, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MACHINERY, APPARATUS, AND WORKS. OF CON--
STRUCTION, INTENDED TO BE EMPLOYED AND THE MODE OR METHOD OF USING OR
EMPLOYING THE SAME FOR THE PURPOSE OF EXAMINING OR REPAIRING SHIPS AND
OTHER VESSELS," to be as follows:-
Instead of docking a ship or other vessel direct upon keel blocks, and
shoreing her between the sides of a pontoon dock or floating dock, whether of
the description patented by me on the Twenty-second day of March, One
thousand eight hundred & sixty, and numbered 746, or in any other form or
description of floating dock; and instead also of sinking a "saucer or hollow

page_text: 66
float, as in use at the Victoria (London) docks and elsewhere, and afterwards
floating it into a recess, "lay "-"by," or dock containing water, that the
bottom of the ship or other vessel may be raised slightly above the water
surface; and instead also of "hauling-up" on an inclined slip or ways" by
any of the methods heretofore used or at present practised, I treat ships or
other vessels in a different manner, and by means of the novel machinery,
apparatus, and works of construction, and the mode or method in which I
employ or work the same or put them respectively into practice, I am enabled
to profitably employ the floating dock in raising and lowering ships, and
disposing of such ships or other vessels in such a manner that the dock is set
at liberty to be employed in raising or lowering other ships, instead of being
exclusively engaged and occupied by any particular vessel during the period of
its being under examination or repair; also by means of the combination of
the several works of construction and the mechanical contrivances employed
upon, in connection with and in aid of the floating dock, a number of ships
may be readily placed in positions advantageous to their being readily and
economically repaired, whilst the floating dock can in turn have its external
bottom and sides readily examined, cleansed, repainted, or repaired within the
float or basin provided in accordance with that part of my present Invention
relating thereto; also by means of the novel construction of caisson or gate
for closing the entrance or openings to floating docks, and docks constructed
of masonry or other material, and whether intended for closing the entranco
of floats, basins, or dry docks, I am enabled more readily and securely than
heretofore to effect the closing and opening of such structures, and at a con-
siderably reduced cost of constructing such caisson or gate as compared with
the ordinary construction of caisson or ship-like structure heretofore
employed.
Upon the floor of a floating dock of the kind or description patented by me
on the Twenty-second day of March last, or upon the floor or upper side of the
bottom portion of any other float or floating dock or pontoon of suitable con-
struction, I place and securely fix two or more edge rails, tramways, or
tram plates of any convenient form, and for the purpose of supporting and
guiding a multi-wheeled or other carriage or bed upon which the ship or other
vessel has to be drawn, when the pontoon or dock is sufficiently submerged,
and upon which it has to be securely blocked, shored, strutted, or stayed, so as
to admit the carriage, together with the ship or other vessel thereupon, being
afterwards moved or hauled off from the pontoon or floating dock. Instead of
a wheeled carriage it may be sledge-like in character, and the friction wheels
may be mounted upon the floating pontoon or dock, and in lines upon the.

page_text: wharf or quay, but whatever the form of the carriage may be it should be
placed in position and properly secured within the floating dock previously
to its being submerged, for the purpose of receiving the ship or other
vessel.
Upon a wharf or quay at a suitable height from a constant water level, or
from a bed line or foundation suitably prepared to receive the pontoon or
floating dock, a corresponding series of edge rails or train plates are pro-
vided, of which several sets may be arranged parallel to each other at a
sufficient distance apart to enable sufficient access to be given; or they may
be arranged radiatory or radiating from a common centre at some distance
from the sea or river face of the wall. By the latter arrangement economy of
basin or float room is effected as compared with the longer line of wharf or
quay wall, which would have to be enclosed according to that part of my
present Invention relating thereto, and as herein-after provided when such
work of construction has to be executed as part of the general arrangement
for docking ships or other vessels, although such enclosed dock or float need
not necessarily be executed excepting in tide ways, or where the level of the
water in front of the wharf or quay wall is liable to fluctuation or where the
depth is insufficient without excavation. As the level of the two lines or sets
of rails upon the floating pontoon or dock, and the wharf or quay respectively
must correspond or be in line and upon the same level, for the purpose of
enabling the carriage containing the ship or other vessel to be readily drawn
off with the least possible power, and without the risk of straining the ship or
displacing it from the carriage.
Where there is no rise or fall of tide, or from other circumstances the
ordinary means of docking ships cannot be resorted to, and also for the purpose
of employing floating docks or pontoons having beds fitted with rails or tram-
ways, upon which a multi-wheeled or other carriage is fitted capable of being
drawn off or removed therefrom, and such apparatus to be used, worked, or
employed in connection with corresponding lines or series of rails or tramways
arranged in parallel or radial sets on land on the top of a line of wharf or
quay, as before described, I enclose a portion of the water space, or excavate
or otherwise form a shallow basin, which need only be of sufficient depth to
admit freely the pontoon or floating dock carrying the vessel. The bottom of
this shallow basin or float must be constructed with a level bed, so that when
the pontoon or dock is floated in, and the caisson or gates closing the entrance
thereof have been replaced, the pontoon or floating dock is allowed to sink on
to the level bed prepared for it; the rails of the floating dock are then brought
into correct position with those on shore, and the carriage upon which the

page_text: ship or other vessel is placed is moved or slid gradually from off the Hoating
dock or pontoon and along the rails or tramways on shore, until it is advanced
into the required position. The floating dock or pontoon is then free to be
undocked or floated out to receive another ship or other vessel, the previous
carriage having been replaced by another, or the dock or pontoon is then
ready to receive a vessel which has been previously raised, placed on shore and
repaired, that it may be again set afloat.
Such basins as I have described may either be constructed by means of
piers or jetties projecting sufficiently far into the water, or by means of suitable
excavations in the land. By making the float or basin of only sufficient size
to admit the floating dock or pontoon, and allow of its commanding the
various lines of rails or trams, it can be employed with advantage for docking,
cleaning, painting, and repairing the floating dock or pontoon; as the caisson
or gates for closing the entrance being shut, the water contained within the
float or basin may be pumped out, and the floating pontoon or dock left dry.
For the purpose of closing the entrance of such basins or floats, and likewise
for closing the entrance to docks and basins generally in substitution for the
ordinary ship-liko form of caisson or for gates, I construct a novel form of
caisson by forming a hollow framed or cellular structure of a form or elevation
suitable for closing the opening and fitting into the grooves formed in the cill
and side walls. I give to the thickness or sectional plan of such caisson a
parabolic or other strong form or shape capable of resisting the pressure due
to the greatest pressure of water behind it, and I attain this with the smallest
thickness and least weight of material, and instead of depending upon the
buoyancy of the lower portion of such structures as is usually the case, I form
on each side and at the top or upper part of such structure a hollow float or
half-boat shaped hollow buoyant vessel, and I fit both the upper and lower
portions of such a caisson with sluices and valves for the admission and
discharge of water. The float or floats being of sufficient capacity when the
water is allowed to escape or otherwise removed therefrom, and may then be
released from its position and floated away. In this respect the caisson con-
structed according to my present Invention is more easily managed, and
greater stability is obtained, and the amount of material and the cost of
making such structures is very materially reduced. For the purpose of
giving a continuous or nearly continuous motion to the carriage with its
super-imposed ship, I combine hydraulic pumps or rams of great power in a
novel manner, and I apply such apparatus in combination with a portable
steam engine mounted upon a strong carriage, running upon the same or other
rails, as those provided upon the shore for receiving the carriage carrying the

page_text: ship; and by means of one or more sets of single or double racks and palls
mounted upon or depending from the portable carriage or framing containing
the steam engine and hydraulic apparatus (which pawls are made to take into
and resist the power exerted by the hydraulic pump or rams whilst pulling or
pushing), I am enabled to maintain a nearly uniform thrust or strain, and a
continuous or nearly continuous and uniform motion of the carriage in either
direction by the admission of water alternately from one pump to others, or
from one set of pumps to another pump or pumps, of arcas correspondingly
proportioned to one another to give out a uniform amount of power in which-
ever direction motion may be required, and thus without reversing the portable
or locomotive engine and hydraulic apparatus, I am enabled either to exert a
thrust or a tractive power, as may be required, for the purpose of hauling on
to the land or pushing off from the land on to the floating pontoon or dock the
carriage containing the ship or other vessel.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Banks Rennie in the Great Seal Patent Office on
the 19th June 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
BANKS RENNIE, of the Firm of George Rennie & Sons, Holland Street,
Blackfriars, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of December, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said George Banks Rennie, Her special licence that I, the said George
Banks Rennie, my executors, administrators, and assigns, or such others as
I, the said George Banks Rennie, 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 "IM-
PROVEMENTS IN MACHINERY, APPARATUS, AND WORKS OF CONSTRUCTION INTENDED
TO BE EMPLOYED, AND THE MODE OR. METHOD OF USING OR EMPLOYING THE SAME FOR
THE PURPOSE OF EXAMINING OR REPAIRING SHIPS AND OTHER VESSELS," upon
the condition (amongst others) that I, the said George Banks Rennie, my

page_text: 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 George Banks Rennie, 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 and accompanying two Sheets of Drawings:-
66
saucer"
Instead of docking a ship or other vessel direct upon keel-blocks, and
shoreing her between the sides of a pontoon dock or floating dock, whether of
the description patented by me on the Twenty-second day of March, One
thousand eight hundred and sixty, and numbered 746, or in any other form or
description of floating dock; and instead also of sinking a
or hollow
float, as in use at the Victoria London Docks and elsewhere, and afterwards
floating it into a recess "lay-by," or dock containing water, that the bottom of
the ship or other vessel may be raised slightly above the water surface; and
instead also of "hauling-up" on an inclined slip or "ways" by any of the
methods heretofore used, or at present practised, I treat ships or other vessels
in a different manner, and by means of the novel machinery, apparatus, and
works of construction, and the mode or method in which I employ or work
the same, or put them respectively into practice, I am enabled to profitably
employ the floating dock in raising and lowering ships, and disposing of such
ships or other vessels in such a manner that the dock is set at liberty to be
employed in raising or lowering other ships, instead of being exclusively
engaged and occupied by any particular vessel during the period of its being
under examination or repair. Also, by means of the combinations of the
several works of construction and the mechanical contrivances employed upon,
in connection with, and in aid of the floating dock, a number of ships may be
readily placed in position advantageous to their being readily and economically
repaired, whilst the floating dock can in turn have its external bottom and
sides readily examined, cleaned, repainted, or repaired within the float or basin
provided in accordance with that part of my present Invention relating
thereto. Also by means of the novel construction of caisson or gate for
closing the entrance or openings to floating docks, and docks constructed
of masonry or other material, and whether intended for closing the entrance
of floats, basins, or dry docks, I am enabled more readily and securely than
heretofore to effect the closing and opening of such structures, and at a con-

page_text: siderably reduced cost of constructing such caisson or gate as compared
with the ordinary construction of caisson or ship-like structure heretofore
employed.
Upon the floor of a floating dock of the kind or description patented by me
on Twenty-second day of March last, or upon the floor or upper side of the
bottom portion of any other float or floating dock or pontoon of suitable con-
struction, I place and securely fix two or more edge rails, tramways or tram-
plates of any convenient form, and for the purpose of supporting and guiding
a multi-wheeled or other carriage, or bed upon which the ship or other vessel
has to be drawn, when the pontoon or dock is sufficiently submerged, and
upon which it has to be securely blocked, shored, strutted, or stayed, so as to
admit the carriage, together with the ship or other vessel thereupon, being
afterwards moved or hauled off from the pontoon or floating dock.
Instead of a wheeled carriage it may be sledge-like in character, and the
friction wheels may be mounted on the floating pontoon or dock, and in lines
upon the wharf or quay; but whatever the form of the carriage may be, it
should be placed in position and properly secured within the floating dock
previously to its being submerged for the purpose of receiving the ship or
other vessel.
Upon a wharf or quay at a suitable height from a constant water level, or
from a bed line or foundation suitably prepared to receive the pontoon or
floating dock, a corresponding series of edge rails or tram plates are provided,
of which several sets may be arranged parallel to each other at a sufficient
distance apart to enable sufficient access to be given; or they may be arranged
radially, or radiating from a common centre at some distance at some distance
from the sea or river face of the wall. By the latter arrangement, economy
of basin or float room is effected as compared with the larger line of wharf or
quay wall which would have to be enclosed according to that part of my
present Invention relating thereto, and as herein-after provided, when such
work of construction has to be executed as part of the general arrangement
of docking ships or other vessels, although such enclosed dock or float
need not necessarily be executed, excepting in tideways, or where the
level of the water in front of the wharf or quay wall is liable to fluctuation, or
where the depth is insufficient without excavations. The level of the two
lines or sets of rails upon the floating pontoon or dock aud the wharf or quay
respectively must correspond, or be in line and upon the same level, for the
purpose of enabling the carriage containing the ship or other vessel to be
readily drawn off with the least possible power, and without the risk of strain-
ng the ship, or displacing it from the carriage.

page_text: When there is no rise or fall of tide, or from other circumstances the
ordinary means of docking a ship cannot be resorted to; and also, for the
purpose of employing floating docks or pontoons having beds fitted with rails
or tramways, upon which a multi-wheeled or other carriage is fitted capable
of being drawn off or removed therefrom, and such apparatus to be used,
worked, or employed in connection with corresponding lines or series of rails
or tramways arranged in parallel or radial sets on land on the top of a line
of wharf or quay, as before described, I enclose a portion of the water space,
or excavate or otherwise form a shallow basin, which need only be of sufficient
depth to admit freely the pontoon or floating dock carrying the vessel. The
bottom of this shallow basin or float must be constructed with a level bed, so
that when the pontoon or dock is floated in, and the caisson or gates closing
the entrance thereof have been replaced, the pontoon or floating dock is
allowed to sink on to the level bed prepared for it; the rails of the floating
dock are then brought in correct position with those on shore, and the carriage
upon which the ship or other vessel is placed is moved or slid gradually from
off the floating dock or pontoon, and along the rails or tramways on shore,
until it is advanced into the required position. The floating dock or pontoon
is then free to be undocked or floated out to receive another ship or other
vessel, the previous carriage having been replaced by another, or the dock or
pontoon is then ready to receive a vessel which has been previously raised,
placed on shore and repaired, that it may again be set afloat.
Such basins as I have described may either be constructed by means of
piers or jetties projecting sufficiently far into the water, or by means of
suitable excavation in the land. By making the float or basin of only suffi-
cient size to admit the floating dock or pontoon, and allow of its commanding
the various lines of rails or trams, it can be employed with advantage for
docking, cleaning, painting, and repairing the floating dock or pontoon, as the
caisson or gates for closing the entrance being shut the water contained within
the float or basin may be pumped out, and the floating pontoon or dock
left dry.
For the purpose of closing the entrance of such basins or floats, and
likewise for closing the entrance to docks and basins generally, in substitution
for the ordinary ship-like form of caisson, or for gates, I construct a novel
form of caisson, by forming a hollow framed or cellular structure of a form or
elevation suitable for closing the opening, and fitting into the grooves formed
in the cell and side walls. I give to the thickness or sectional plan of such
caisson a parabolic or other strong form or shape, capable of resisting the
pressure due to the greatest pressure of water behind it, and I attain this with

page_text: the smallest thickness and least weight of material; and instead of depending
upon the buoyancy of the lower portion of such structures, as is usually the
case, I form on each side, and at the top or upper part of such structure, a
hollow float or balf boat-shaped hollow buoyant vessel; and I fit both the
upper and lower portions of such caisson with sluices and valves for the
admission and discharge of water. The float or floats being of sufficient
capacity, when the water is allowed to escape, or otherwise removed therefrom,
the caisson may then be released from its position and floated away. In this
respect the caisson constructed according to my present Invention is more
easily managed, and greater stability is obtained, and the amount of material,
and the cost of making such structures is very materially reduced.
For the purpose of giving a continuous or nearly continuous motion to the
carriage with its superimposed ship, I combine hydraulic pumps or rams of
great power in a novel manner; and I apply such apparatus in combination
with a portable steam engine mounted upon a strong carriage running upon
the same or other rails as those provided upon the shore for receiving
the carriage carrying the ship; and by means of one or more sets of single or
double racks and palls mounted upon or depending from the portable carriage
or framing containing the steam engine and hydraulic apparatus (which palls
are made to take into and resist the power exerted by the bydraulic pumps or
rams whilst pulling or pushing,) I am enabled to maintain a nearly uniform
thrust or strain, and a continuous or nearly continuous and uniform motion of
the carriage in either direction, by the admission of water alternately from
one pump to others, or from one set of pumps to another pump or pumps, of
areas correspondingly proportioned to one another to give out a uniformi
amount of power in whichever direction motion may be required; and thus,
without reversing the portable or locomotive engine and hydraulic apparatus,
I am enabled either to exert a thrust or a tractive power, as may bo required
for the purpose of hauling on to the land, or pushing off from the land on
to the floating pontoon or dock the carriage containing the ship or other
vessel.
Although I have herein-before referred to the wheeled carriage for receiving
the vessel to be docked as being secured withing the floating dock previously:
to such dock being submerged, I may prefer in some cases to proceed some-
what differently, and as follows:-The ship or other vessel to be docked may,
as a preliminary operation, be allowed in the first instance to be deposited
upon keel blocks upon the floor of the floating pontoon or dock of the kind
or description herein-before referred to. The wheeled carriage may then be
introduced under the keel of the ship; the keel blocks being gradually removed

page_text: from thereunder, and the carriage slid in, so that the vessel may be hauled off
the .blocks, and, by means of the multi-wheeled carriage herein-before
described, be received from the floor of the floating pontoon or dock, and
placed in any position on shore for the purpose of examination or repair.
In some cases it may be desirable to receive the vessel upon the carriage or
cradle contained within the floating dock or pontoon direct, and by means of
shores in the ordinary way secure the vessel within and to the sides of the
dock until the dock and vessel have been raised, when, if found necessary, the
proper and necessary blockings and means of securing the ship to the carriage
may be proceeded with.
In the accompanying two Sheets of Drawings, Figs. 1, 2, & 3, Sheet 1,
exhibit the general arrangement of the mode or method in which I construct
basins, floats, or docks, and shews two of the arrangements of rails or ways
upon the wharf or quay, by which the ship or vessel contained within the
floating dock or upon a pontoon can be hauled therefrom; and by means of
suitable apparatus the ship and the carriage or cradle upon which it has been
placed may be disposed upon either of the lines or ways, and the floating dock
or pontoon set free for other employment.
Figs. 4 and 5, Sheet 1, shew the novel form of caisson or apparatus for closing
the entrance of docks and such like openings, and for other similar purposes.
In Sheet 2, Fig. 1 is a side elevation; Fig. 2 an end view, partly in section;
Fig. 3 a sectional plan view of the steam propelled hydraulic tracto-motive
apparatus for hauling off or propelling in either direction the multi-wheeled or
other carriage, platform, or cradle upon which the ship or other vessel or body
is placed or securely mounted for the purpose of being transported from the
floating dock, pontoon, or vessel on to the wharf, quay, or other properly pre-
pared place on shore, as herein-before described and as herein-after set forth.
In Fig. 1, Sheet 1, a ground plan of the general arrangement of the basin
or float, and the land apparatus or contrivance for receiving the ships or other
vessels from off the pontoon or floating dock is shown in illustration of the
radial arrangement or disposition of the rails, trams, or other ways for
receiving the carriages, platforms, or cradles, with their superimposed loads,
so as to economize space on shore, as well as to reduce the water area or
capacity of the basin or float. Fig. 2 is a ground plan of a similar basin or
float, and the rails, trams, or ways, but the latter are shown as parallel to
each other, and the basin or float has parallel sides. In these views the
entrance to each basin or float is shown as fitted with (for the purpose of
closing it) a caisson constructed according to the present Invention, although
any other form of caisson or gate may be adopted. Fig. 3 is a vertical section

page_text: of the float or basin, which in this case is shown as being an enclosed water
space formed by means of surrounding walls of masonry or other suitable
material, and the quay or wharf on which the ships or other vessels are drawn
from the floating dock or pontoon for the purpose of examination or repair.
In these Figures A, A, represents the surrounding walls or enclosure forming
the basin or float; B, the bottom thereof, which should be levelled, or be
formed of masonry where practicable; C, the face wall of the quay or wharf;
D, the caisson for closing the entrance of the basin or float; E, the floating
dock or pontoon, on the floor of which provision is made for enabling the ship
or other vessel to be moved, together with the carriage or cradle on which it
rests, on to the wharf or quay, where similar provisions are made for enabling
the vessel to be readily transported thereon; F, F, F, are rails, trams, tracks,
or ways corresponding with those on the floor of the pontoon or dock; upon
these the carriage or cradle, with the ship or vessel secure thereupon, is trans-
ported along to the required extent for the purpose of examining or repairing
the ship or vessel on shore whilst the floating dock or pontoon is set free, that
it may be employed in docking or removing some other ship. Between these
ways, or on each side thereof, or both between and on each side thereof,
suitable lines of racks, or their mechanical equivalents, are fitted for the
purpose of enabling the tracto-motive power, or alternately hauling and forcing
apparatus, to be attached to or connected with, for the purpose of operating
upon or moving each carriage or cradle, together with the vessel secured
thereupon; G, G, G, &c.; exhibit some of the modes or methods in which it is
preferred to arrange and apply the power for this purpose.
Figs. 4 & 5 are illustrations of caissons constructed according to the present
Invention, but the form as well as the proportion of the upper and buoyant or
floatative portion, as well as the general proportion and arrangement of the
parts, may be varied to suit the particular application or the circumstances
connected with the use or employment of such apparatus. a is the frame or
outline of the caisson, the dimensions of which are regulated by the size of the
dock entrance or opening it has to fill. The enlargement of the width of the
lower portion, as shown at 6, is given for the purpose of ensuring the requisite
amount of strength or ability to resist the pressure with the least weight of
material, c, being the upper or buoyant portion of the caisson of a boat-
like form, as herein-before described. These caissons are fitted with sluices
and valves for the admission and escape of water, as well as pumps, in manner
similar to the ordinary caissons at present in use.
In Sheet 2, Figs. 1, 2, and 3 illustrate one of the modes or methods which
I prefer to employ for giving motion to the carriage or cradle, and Fig. 4

page_text: a, a,
exhibits a detail in transverse vertical section of that part of the hydraulic
apparatus forming the connection between the pumps and the rams and the
cylinder by which the power is transmitted from one cylinder or set of
cylinders to another for the purpose of producing a continuous or nearly
continuous motion of the tracto-motive apparatus in either direction.
Figs. 1 and 2, are longitudinal blocks of timber, upon which is mounted a
series of plates or combined rails, guides, and racks. A carriage composed of
iron framing, as at c, c, &c., is mounted upon wheels or rollers d, d, &c., and
upon this carriage or frame is mounted, as shown, a steam boiler A and steam
cylinder B, into which steam is admitted by means of a steam pipe C, and
from which the steam after it has been used is exhausted into the chimney by
the pipe D, a fly wheel E being keyed upon a crank shaft to regulate the
motion of the engine, and the pumps are set in motion by the steam engine,
and the water forced therefrom is admitted to the interior of each of the
moving cylinders e, e, &c., by means of openings through the centre of each
fixed plunger or ram f, first to the large central cylinder, which having been
made to traverse to the end of its stroke by sliding along the bearing and
guiding surfaces g, g, of the main frame of the carriage, the water is then
admitted into the two smaller cylinders under the requisite pressure, and they
in turn are caused to move along in the guides provided for them, as shown,
and thus whilst the action is reversed, motion is communicated to the main
carriage by means of palls h, h, attached to one or both ends of each cylinder,
which palls take into the racks provided for them. A mode of admitting and
regulating the supply of water to these cylinders is shown in Fig. 1 at i, and in
the detached view, Fig. 4; but this, of course, may be varied as may be found
necessary. F, F, coupling links connected with the main framing at each end,
by which the pall or thrust may be given direct to the carriage or cradle, or by
means of chains or other connections, may be communicated indirectly thereto.
Instead of employing the hydraulic pressure within moving cylinders, the
plungers or rams may be caused to move thereby and to act upon fixed or
moveable chains, or the plungers may be formed hollow like the pistons of
double trunk engines, and the chains be permitted to pass through the centre
thereof, and a grip or hold thereon be secured by means of self-acting grippers
or palls.
Having now described the nature of my present Invention, and illustrated
in the accompanying two Sheets of Drawings some of the modes or methods
in which I prefer to put each of the several parts of the same into practice, I
wish it to be understood that I do not, however, confine myself to the precise
mechanical disposition and arrangement of parts, nor to the respective pro-

page_text: portions of the several parts shewn on the Drawings, as such may, of course, be
varied according to the requirements of or circumstances connected with each
application of my said Invention; and, moreover, other equivalent mechanical
parts or pieces of mechanism may be substituted for those I have shewn or
herein described. What I claim is,-
First, the novel arrangement for lifting and removing ships, and placing
them on shore in such positions as they can conveniently be examined,
repaired, or otherwise treated or operated upon, and be afterwards readily
removed, as herein described.
Second, the combination of a float or basin, as described, for containing the
floating dock or pontoon, with a series of lines of rails, trams, or other
ways," arranged or disposed on shore, as described, and a carriage or cradle
constructed to carry a ship or other vessel, and to rest upon the bottom of the
floating dock or pontoon, and from which it may be drawn or hauled off on to
the lines of rails, trams, or other "ways" provided on shore, whatever form,
kind, or description of apparatus may be employed for the purpose of hauling
off or replacing the carriage or cradle and its load.
Third, the novel form of caisson, and the mode or method of constructing
the same, as herein described, in which the buoyant power or means of
floating and moving the caisson is provided and disposed, as shewn and
described.
Fourth, the tracto-motive apparatus described, for the purpose of hauling,
propelling, or otherwise giving motion to carriages or cradles containing or
having mounted thereupon a ship or other vessel.
In witness whereof, I, the said George Banks Rennie, have hereunto set
my hand and seal, this Eighteenth day of June, One thousand eight
hundred and sixty-one.
GEORGE BANKS RENNIE. (L.S.)
Witness,
F. H. ROBERTS,
19, Salisbury Street, Adelphi.