AN IMPROVEMENT IN THE CONSTRUC- TION OF AND IN THE MODE OF OPENING AND CLOSING OF MOVEABLE BRIDGES OR ARCHES, FOR THE PURPOSE OF CARRYING RAILWAYS, TRAMWAYS, OR OTHER ROADS ACROSS CANALS, Locks, Docks, OR OTHER OPEN CUTTINGS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
HASKINS GANDELL and JOHN BRUNTON, of Birkenhead, in the County of
Chester, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, the Twenty-third day of March, in the
year of our Lord One thousand eight hundred and forty-six, in the ninth year
of Her reign, did give and grant unto us, the said John Haskins Gandell and
John Brunton, our exors, admors, and assigns, Her especial licence, full
power, sole privilege and authority, that we, the said John Haskins Gandell
and John Brunton, our exors, adiñors, and assigns, and such others as we,
the said John Haskins Gandell and John Brunton, our exors, admors, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within that part of the United
Kingdom of Great Britain and Ireland called England, the Dominion of
Wales, the Town of Berwick-upon-Tweed, and all Her said Majesty's Colonies
and Plantations abroad, our Invention of "AN IMPROVEMENT IN THE CONSTRUC-
TION OF AND IN THE MODE OF OPENING AND CLOSING OF MOVEABLE BRIDGES OR
ARCHES, FOR THE PURPOSE OF CARRYING RAILWAYS, TRAMWAYS, OR OTHER ROADS
ACROSS CANALS, Locks, Docks, OR OTHER OPEN CUTTINGS;" in which said Letters
Patent there is, amongst others, contained a proviso that if we, the said John
Haskins Gandell and John Brunton, should not particularly describe and ascer-
tain the nature of our said Invention, and in what manner the same is to be
"

page_text: performed, by an instrument in writing under our hands and seals, or under
the hand and seal of one of us, and cause the same to be enrolled in Her
said Majesty's High Court of Chancery within two calendar months next and
immediately after the date of the said recited Letters Patent, that then the
said Letters Patent, and all liberties and advantages whatsoever thereby
granted, should utterly cease, determine, and become void, as by the said
Letters Patent, reference being thereunto had, will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said recited proviso, we,
the said John Haskins Gandell and John Brunton, do hereby declare the
nature of our Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by these Presents and the
Drawings therein referred to and hereunto annexed.
Our improvement in the construction of moveable bridges consists in a
moveable trussed bridge or viaduct moving on a horizontal axis or shaft A,
which axis or shaft is supported at various points of its length, as the case
may require, in plummer blocks or bearings, allowing the said axis or shaft to
revolve freely, the said plummer blocks or bearings resting on a solid mass
of masonry or other substantial material. On this axis or shaft we fix large
plates B, with diverging or radiating mortices for the reception and support
of a sufficient number of strutts or beams C, C, &c. extending in direct or
curved lines to transverse bearers D, D, &c., which form the support of the
longitudinal beams or platform E, and which strutts are further supported by
diagonal braces. The said longitudinal beams or platform are so constructed
as to carry railways, carriage roads, or any other kind of road, highway, or
path that the traffic may require, and in length will in most cases be nearly
twice the width of the opening it is intended to cross. The projecting or
longer end of the platform F, G, abuts against a strong frame of wood, iron,
or other substantial material H, forming the opposite side of the opening to
be crossed I, K, and supporting the continuation of the roads or railways,
while the other or shorter end of the platform L, F, is supported, level or in a
line with a projected part of the roads or railways M, by strong palls or strutt
beams N yet to be described. For the purpose of balancing the said trussed
platform when moved from its position as a bridge or viaduct, we construct,
at some convenient distance from the centre of the axis or shaft, and between
the diverging beams or strutts, one or more sectors or arcs O, to which are
attached two or more chains P, whereby the whole trussed platform or frame-
work is connected by a rod or rods Q to one or more pistons R, which, on
the movement of the said platform from its level position as a bridge or via

page_text: sure.
duct, are forced into their respective cylinders S, and thereby displace a quan-
tity of water with which they are filled, and which water is thus made to
ascend vertically in a large pipe or tank T, of such dimensions and of such
form that the height, and consequent statical pressure of the ascending column
of water against the piston or pistons may increase in proportion as the weight
of the platform and framework increases against the said pistons during its
movement from its position as a bridge or viaduct to its open position, as
shewn in Figure 2. The statical pressure of the said column of water will
have a constant tendency, by its action against the piston or pistons, to restore
the platform to its level position as a bridge or viaduct; and the height of
the column must be adjusted in each case so as to ensure the requisite pres-
For the purpose of removing the trussed platform from its position as
a bridge or viaduct, as shewn in Figure 1, to its position, as shewn in Figure 2,
we attach, by a connecting rod or rods U to the upper surface of the said
trussed platform, a piston or ram V working in a hydraulic cylinder W, which
said piston or ram is acted upon by a statical pressure of water sufficient to
retain the said trussed platform in its position, as shewn in Figure 2, so long
as the said pressure is permitted to act against the said piston or ram; and
when it is required to restore the trussed platform to its level position as a
bridge or viaduct, as shewn in Figure 1, the said statical pressure is removed,
and as the water flows out of the said hydraulic cylinder, the said trussed plat-
form gradually resumes its position. For the purpose of supporting the short
end L, F, of the said trussed platform in its level position as a bridge or viaduct,
we construct a strong wall X of masonry or other substantial material, which
also forms the end of a chamber in which the trussed platform moves, when
opened, as in Figure 2. Supported by and strongly affixed to this, we place
4 or more palls or strutts N, N, which, upon the trussed platform resuming
its position as a bridge or viaduct immediately fall, behind it, and prevent its
moving until the palls or strutts are simultaneously lifted by levers Y, fixed on
a shaft.
When the width or opening to be crossed is too great for one such
trussed platform as has been described, we place on each side of such opening
a moveable trussed platform, the longer end of each abutting or meeting
together at the centre of such opening.
Having thus described the nature of our Invention, and the manner in
which the same is to be constructed and used, we would have it clearly
understood that we do not confine ourselves to the precise details herein
described so long as the peculiar character of our Invention, or of any part
of our Invention be retained; but what we claim is,―
1st, a trussed bridge or viaduct moveable about an axis, and constructed as

page_text: above described; and that there may be no ambiguity in the term "trussed
bridge," we hereby further declare that we mean by those terms a bridge in
which the whole stress is borne by trussed beams in the direction of their
length, and is ultimately passed through them into the axis or shaft upon
which the whole is made to rest and move.
2nd, we claim the improvement in the opening and closing of moveable
bridges and arches, which consists in the balancing and maintaining the whole
in an uniform state of manageable equilibrium during any part of its oscil-
latory motion, by means of the statical pressure of a vertical column of water,
as above described, the said balancing power being also made available for
restoring the trussed platform to its position as a bridge or viaduct, and of
applying the same at a level blow the upper surface of such trussed platform.
3rd, we claim the improvement in the opening and closing of moveable
bridges or arches, which consist in moving the platform from its level position
as a bridge or viaduct to such a position as will permit ships or other things
to pass through the space it occupied, and by means of the statical pressure of a
column of water acting on a piston or pistons in restoring each platform again
to its position in such bridge or viaduct, as above described.
In witness whereof, I, the said John Haskins Gandell, have hereunto
set my hand and seal, this Twenty-third day of May, in the year of
our Lord One thousand eight hundred and forty-six.