IMPROVEMENTS IN THE CONSTRUCTION OF IRON BEAMS FOR THE ERECTION OF BRIDGES AND OTHER STRUCTURES
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
FAIRBAIRN, of Manchester, in the County of Lancaster, Civil Engineer, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by
Her Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eighth day of October, in the tenth year of Her reign, and
in the year of our Lord One thousand eight hundred and forty-six, did, for
Herself, Her heirs and successors, give and grant unto me, the said William
Fairbairn, Her especial licence, full power, sole privilege and authority, that I,
the said William Fairbairn, my executors, administrators, and assigns, and
such others as I, the said William Fairbairn, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time
and at all times during the term of years therein expressed, should and
lawfully might make, use, exercise, and vend, within England and Wales
and the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN
THE CONSTRUCTION OF IRON BEAMS FOR THE ERECTION OF BRIDGES AND OTHER
STRUCTURES;" in which said Letters Patent is contained a proviso that I, the
said William Fairbairn, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed, to be
inrolled in Her Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and at
large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Fairbairn, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, is particularly
described and ascertained in and by the Drawings hereto annexed, and the
following explanations thereof, that is to say :-
My Improvements in the Construction of Iron Beams for the Erection of
Bridges and other Structures consist in the novel application and use of plates
of metal united by means of rivets and angle iron for such or similar purposes,
and forming by such combination a hollow iron beam or girder. But in order
that my Invention may be more explicitly detailed and rendered perfectly
intelligible, I have attached to these Presents three Sheets of Drawings illus-
trative of the peculiar modes of construction of such hollow beams or girders,
and also of their practical use in erecting bridges or other buildings.
In Sheet 1, Figure 1 represents a side elevation of part of a hollow iron beam
or girder, and Figure 2 a transverse section of the same, shewing its mode of
construction. Figure 8 is a plan or horizontal view of the top of the hollow
beam or girder; and Figure 4 is a plan or horizontal view of the bottom of
such beam or girder, shewing, some peculiarity in the modes of rivetting the
plates together, as will be hereafter explained. a, a, are the side plates;
b, b, the bottom plates; c, c, the vertical angle or T iron for connecting the
plates a, a,, by means of the covering plates or irons d, d, and the rivets e, e..
These side plates are all to be put together with butt joints, and rivetted either
by machinery. qr by hand, exactly in. a similar manner to ordinary boiler
making. The top of this hollow beam. or girder is formed by two or more
rectangular cells or hollow chambers, composed of plates f,f,f,f, and ordinary
angle or iron 9, 9, 9, 9, being fastened together by the rivets h, h, h, h,
attached to the side plates a, a, by the angle iron i, i. The bottom of this
hollow beam or girder is formed of the plates b,.b, b, b, being fastened together
by means of the covering plates. k, k, and rivets I, I, I, I, and attached to the
side plates.by the angle irons m, m. The top of the hollow beam or girder
is constructed of cast or malleable iron, and of any convenient form, either
cellular or rectangular, as shewn in Figure 2, or of an elliptical form, as shewn
in Figure 4, Sheet 2 (where it is represented of cast iron), or of any other
suitable shape calculated to prevent the top giving way or puckering from
compression; or other variations in the method of constructing the top of the
beam may be adopted, namely, either by employing thick metallic plates to
form the top, or by lighter iron plates arranged so as to form hollow cells, as
may be most convenient, for the purpose of resisting a crushing force and
retaining the beam in shape. The bottom of the hollow beam or girder is

page_text: constructed of a series of plates b, b, either of a single or double thickness,
rivetted together by means of covering plates k, k, placed over the butt joints
and rivets I, l. These plates b, b, are united to each other by alternating or
crossing the joints, and by a peculiar mode of rivetting the same, which is best
seen in Figure 4. This novel mode of rivetting. I call "chain rivetting, as
it forms an entire chain of plates throughout the structure, and so unites
the covering plates over the joints as not to weaken or injure the plates, by
transverse rivets, but to form a connecting link to each joint by a series of
longitudinal rivets or pins, as shewn at Figure 4. This novel mode of rivetting
is of great importance in retaining the strength of the plates, and greatly con-
tributing to their powers of resistance to a tensile strain.
23
In Sheet 2 of the Drawings, Figure 1 represents a side elevation, and
Figure 2 a transverse section, of part of a hollow iron beam or girder, wherein
the sides or plates a, a, are composed of sheet iron and rivetted to the top and
bottom plates b, b, by means of angle iron c, c, in the ordinary manner. This
construction of hollow beam or girder I consider the most suitable for the
usual purposes of building mills, factories, warehouses, dwelling houses, &c.,
whereas those formerly described (with reference to Sheet 1) are more suitable
for the erection of bridges, viaducts, and other similar works. Figure 8
represents a side elevation, and Figure 4 a transverse section, of part of a
hollow iron beam or girder constructed in a similar manner to that in Sheet 1,
excepting that, instead of the rectangular plate iron top, this variation has an
elliptical or other shaped cast-iron top f.ff, which is cast in suitable or con-
venient lengths, and fastened by means of rivets to the side plates or sheets
a, a, the several lengths or castings being connected together by flanches g, g,
in a similar manner to ordinary water pipes, the joints being protected by a
cap or cover h, h.
In Sheet 8 of the Drawings, Figure 1 represents a side elevation of a hollow
girder bridge erected or constructed upon the principle of my Invention, and
shewing the practical application of the hollow iron beam or girder to such or
similar purposes. Figure 2 is a transverse section of the same taken at the
line A, B, in Figure 1. c, c, c, c, are hollow iron beams or girders forming
the sides of the bridge, and D, D, a central hollow beam or girder (nearly
double the strength of the sides), all being supported at each end by suitable
fastenings, piers, &c. E, E, are hollow iron cross beams for sustaining the
roadway F, F, Figure 8 being a cross section of such beam. The girders
C and D are constructed according to the plan detailed in Sheet 1 of the
Drawings, and the cross beams E somewhat similar to those in Sheet 2,
Figures 1 and 2, thus shewing their several adaptations and modes of use.

page_text: Having now fully described the nature of my said Invention, and the manner
in which the same is to be performed, I desire it to be understood that I claim
the novel application and use of plates or sheets of iron united by means of
angle iron and rivets, or by other means, for forming or constructing by such
combination hollow beams or girders for the erection of bridges and other
buildings, whether constructed exactly according to the several Figures repre-
sented in the Drawings annexed and above described, or in any other manner
or form which shall embrace the principles of my Invention.
In witness whereof, I, the said William Fairbairn, have hereunto set my
hand and seal, this Seventh day of April, One thousand eight hundred