IMPROVE- MENTS IN TRUSSED IRON BRIDGES
Year: 1857

page_text: LETTERS PATENT to Arthur Challis Kennard, of the Falkirk Iron Works,
in the County of Stirling, North Britain, for the Invention of "IMPROVE-
MENTS IN TRUSSED IRON BRIDGES."- A communication.
Sealed the 6th April 1858, and dated the 22nd December 1857.
PROVISIONAL SPECIFICATION left by the said Arthur Challis Kennard
at the Office of the Commissioners of Patents, with his Petition, on the
22nd December 1857.
I, ARTHUR CHALLIS KENNARD, of the Falkirk Iron Works, in the County of
Stirling, North Britain, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN TRUSSED IRON BRIDGES," to be as follows:-
The improvements consist in constructing the diagonal struts and ties of
trussed iron bridges of an angular or V-shape, framed or consisting of angle
or tee iron, or other suitable sections of iron, by which means increased
lateral stiffness is obtained in the structure.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Arthur Challis Kennard in the Great Seal Patent Office on
the 21st June 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
CHALLIS KENNARD, of the Falkirk Iron Works, in the County of Stirling,
North Britain, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of December, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twenty-first year
of Her reign, did, for Herself, Ier heirs and successors, give and grant
unto me, the said Arthur Challis Kennard, Her special licence that I, the said
Arthur Challis Kennard, my executors, administrators, and assigns, or such
others as I, the said Arthur Challis Kennard, my executors, administrators, and
assigus, 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 "IMPROVEMENTS IN TRUSSED IRON BRIDGES," a communication, upon the
condition (amongst others) that I, the said Arthur Challis Kennard, 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 ba
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 1, the said Arthur Challis Kennard, do hereby declare
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, reference being had to the accompanying Drawing, and to
the figures and letters marked thereon, that is to say:
Figure 1 of the accompanying Drawing is an elevation; and Figure 2 is a
plan of a trussed iron bridge constructed according to the Invention;
Figure 3 is a transverse section of the same on a larger scale; Figure 4 is an
elevation; and Figure 5 is a section of one of the joints of the diagonal struts
with the tension bar on a still larger scale; Figure 6 is a transverse section
of the strut; Figure 7 is a section at the line b, b, in Figure 3. The same
letters refer to similar parts in each Figure.
A is the top rail or compression bar; B is the bottom rail or tension bar;
C, C, are the diagonal struts and ties; D, D, are transverse, wrought-iron
girders, which support the road or railway; E, E,,are pedestals or supports
of cast iron which carry the girders D; F, F, are horizontal cross ties bolted
to the girders D.
The top rail A consists of two vertical wrought-iron plates or bars d, d,
united by angle irons e, e, to two horizontal bars f, f, and another horizontal 1
bar or plate g. The two vertical plates d, d, are also connected at intervals

page_text: by cast-iron distance pieces h rivetted to them. The bottom rail consists of
two pairs of wrought-iron bars i, i, j, j, placed at a sufficient distance apart to
receive the castings E, to which the transverse girders D are secured by bolts
and nuts. The castings E are secured to the bottom rail by the large bolts G.
The diagonal struts and ties C are of an angular or V-form, each branch of
which consists of a plate or bar k with a tec-iron 7 rivetted to it. The plate
or bar projects at each end beyond the tee-iron, and is strengthened by other
short plates m and n rivetted to it. The plates k and m enter between the
vertical plates d, d, of the top rail, and are secured by a bolt H or rivets.
The plates k and n of one branch of the strut enter between the plates i, i, of
the bottom rail, and the plates & and n of the other branch of the strut enter
between the plates j, j, and the whole are secured by the bolt G. The upper
parts of the tee-irons 1, 1, are connected by triangular plates or gusset pieces p
rivetted to them. The tee-irons are cut away at the upper part to allow them
to come together and abut against each other. The transverse girders D
being bolted to the castings or pedestals E, and these pedestals being con-
nected at each end to the branches of the angular struts and ties, the whole
structure is rendered stiff and strong in a lateral direction, and the lateral
deflection of the top rail is prevented without the necessity of employing
diagonal cross ties between the top rails. The particular mode of connecting
the angular struts and ties to the transverse girders may be varied, provided
the connection be stiff and strong in the lateral direction or transverse to the
bridge.
Having now described the nature of the said Invention, and in what manner
the same is to be performed, I wish it to be understood that what I claim is,
constructing trussed iron bridges with parallel top and bottom rails, and
diagonal wrought-iron struts and ties of angular or V-form connected at their
bases to the transverse girders, as herein-before described.
In witness whereof, I, the said Arthur Challis Kennard, have hereunto
set my hand and seal, this Tenth day of June, in the year of our Lord
One thousand eight hundred and fifty-eight.
ARTHUR CHALLIS KENNARD. (L.S.)