IMPROVEMENTS IN THE CONSTRUCTION OF THE PIERS OF BRIDGES AND VIADUCTS
Year: 1873

page_text: LETTERS PATENT to Jolin Dixon, of No. 1, Laurenco Pountney Hill,
in the City of London, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF THE PIERS OF BRIDGES AND VIADUCTS."
Sealed the 17th June 1873, and dated the 18th January 1873.
PROVISIONAL SPECIFICATION left by the said John Dixon at the
Office of the Commissioners of Patents, with his Petition, on the
18th January 1873.
I, JOHN DIXON, of No. 1, Laurence Pountney Hill, in the City of
London, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN THE CONSTRUCTION OF THE PIERS OF BRIDGES AND VIADUCTS," to be
as follows:-
This Invention has for its object to construct the piers for bridges and
viaducts of tubular iron pillars, in which as small an amount of iron is
used as is practicable. For this purpose I construct the pillars of tubes
made from plates of iron bent into a cylindrical form, and rivetted

page_text: together. The whole of the iron used thus forms part of the tubular
shell and is available for sustaining the load to be placed upon it, and no
part of the metal is used simply for bracing or stiffening the tube to
enable it to maintain its shape or to prevent its bulging or bowing out
from a straight line.
In order to stiffen the tubes I fill them up with concrete, which
when set not only maintains the tubes in form but also aids in support-
ing the load placed upon them. The pillars may be erected in pairs
either vertically or slightly inclined to one another, and are braced
together at intervals. The pillars might also be erected in sets of four
or otherwise if desired.
Each tubular pillar I prefer to form of lengths of tube cach of a height
equal to the width of the plate from which it is made. I also prefer to
make each length of. tube slightly taper so that the larger end of one
tube may fit over the smaller end of the next tube, and be united to it 1
by rivetting.
The tubular pillars may also either be made of equal diameter from
top to bottom, or if the pillars are of considerable height the tubes may
gradually be made smaller in diameter towards the top of the pillar.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Dixon in the Great Seal Patent Office on
the 17th July 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DIXON, of No. 1, Laurence Pountncy Hill, in the City of London, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of January, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-sixth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John Dixon, Her special license, that I,
the said John Dixon, my executors, administrators, and assigns, or
such others as I, the said John Dixon, my executors, administrators,
and assigns, should at any time agree with, and no others, from timo

page_text: 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 "IMPROVEMENTS IN THE CONSTRUCTION
OF THE PIERS OF BRIDGES AND VIADUCTS," upon the condition (amongst
others) that I, the said John Dixon, 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 John Dixon, do hereby declaro
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention has for its object to construct the piers for bridges and
viaducts of tubular iron pillars, in which as small an amount of iron is
used as is practicable. For this purpose I construct the pillars of tubes
made from plates of iron bent into a cylindrical form and rivetted
together. The whole of the iron used thus forms part of the tubular
shell and is available for sustaining the load to be placed upon it, and
no part of the metal is used simply for bracing or stiffening the tube to
enable it to maintain its shape or to prevent its bulging or bowing out
from a straight line.
In order to stiffen the tubes I fill them up with concrete, which when
set not only maintains the tubes in form but also aids in supporting the
load placed upon them. The pillars may be erected in pairs either
vertically or slightly inclined to one another, and are braced together at
intervals. The pillars might also be erected in sets of four or otherwise
if desired.
Each tubular pillar I prefer to form of lengths of tube cach of a height
equal to the width of the plate from which it is made. I also prefer
to make cach length of tube slightly taper so that the larger end of one
tube may fit over the smaller end of the next tube, and be united to it
by revetting..

page_text: The tubular, pillars may also either be made of equal diameter from
top to bottom, or if the pillars are of considerable height the tubes may
gradually be made smaller in diameter towards the top of the pillar.
In witness whereof, I, the said John Dixon, have hereunto set my
hand and seal, this Sixteenth day of July, in the year of our 5
Lord One thousand eight hundred and seventy-three.