IMPROVEMENTS IN THE MANUFACTURE OF IRON PIERS OR ERECTIONS, APPLICABLE MORE ESPECIALLY FOB CARRYING BRIDGES AT HIGH ELEVATIONS, OR AVAILABLE FOR SHEER LEGS
Year: 1865

page_text: LETTERS PATENT to Charles de Bergue, of 10, Strand, in the City of
Westminster, Engineer, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF IRON PIERS OR ERECTIONS, APPLICABLE MORE ESPECIALLY FOB
CARRYING BRIDGES AT HIGH ELEVATIONS, OR AVAILABLE FOR SHEER LEGS AND
Sealed the 1st December 1865, and dated the 5th June 1865.
PROVISIONAL SPECIFICATION left by the said Charles de Bergue at the
Office of the Commissioners of Patents, with his Petition, on the 5th
June 1865.
I, CHARLES DE BERQUE, of 10, Strand, in the City of Westminster, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF IRON PIERS OF ERECTIONS, APPLICABLE MORE ESPECIALLY FOR
CARRYING BRIDGES AT HIGH ELEVATIONS, OR AVAILABLE FOR SHEER LEGS AND
LIGHTHOUSES," to be as follows:
My said Invention embraces improved foundations for the lower portion of:
the piers or erections, and also improved superstructure for their upper.
portion.

page_text: My improved foundations consist of a combination of caissoon arrangements
of cylinders or of iron plates to form caissoon cylinders or chambers for sinking
into the ground, the combined structure being narrowed or tapered in dimen-
sions from the base upwards, and such narrowing or tapering being effected
by the several lengths of separate caissoons, which are secured one upon
another, being themselves tapered, or if cylindrical or uniform each in itself
then the several caissoons being successively of smaller diameter or dimensions
so as to produce the general tapering by a series of sets-off or steps.
My improved superstructure to be erected on the improved or other
foundations consists in combining into a structure by ties or struts, or by both
ties and struts, two or more compound columns or pillars of the following
specific character or features, the said columns not standing vertically but being
wider apart at the base than above, and nearing each other, reckoning from
the base upwards, and in some instances uniting at the top, for which purpose
parts of the columns are removed, or are not required to be constructed so
that they may lie and fit properly against each other. The said character or
features of the columns consists in their being constructed with three or more
principal ribs or vertebra connected together with ties and struts on the lattice
principle on each face or side, so as to form lattice columns with three or
more sides.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles de Bergue in the Great Seal Patent Office on the
5th December 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
DE. BERGUE, of 10, Strand, in the City of Westminster, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of June, in the year of our Lord One
thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Charles de Bergue, Her special licence that I, the said Charles de Bergue,
my executors, administrators, and assigns, or such others as I, the said Charles
de Bergue, my executors, administrators, and assigns, should at any t 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

page_text: vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE MANUFACTURE
OF IRON PIERS OR ERECTIONS, APPLICABLE MORE ESPECIALLY FOR CARRYING BRIDGES
AT HIGH ELEVATIONS, OR AVAILABLE FOR SHEER LEGS AND LIGHTHOUSES," upon the
condition (amongst others) that I, the said Charles de Bergue, 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 Charles de Bergue, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the accompanying illustrative
Drawings, and to the figures and letters marked thereon for the purpose of
such reference, that is to say:-
T
My said Invention embraces, firstly, improved foundations for the lower
portion of the piers or erections; and, secondly, improved snperstructure for
their upper portion.
Firstly, my improved foundations consist of a combination of caissoon
arrangements of cylinders or of iron plates to form caissoon cylinders or
chambers for sinking into the ground, the combined structure being narrowed
or tapered in dimensions from the base upwards, and such narrowing or
tapering being effected by the several lengths of separate caissoons, which are
secured one upon another, being themselves tapered; or if cylindrical or
uniform each in itself, then the several caissoons being successively of smaller
diameter or dimensions, so as to produce the general tapering by a series of
sets-off or steps. It is apprehended that this improvement will be found of great
value, not only as diminishing the amount of concrete or other filling, and in
this respect the weight upon the ground at the bottom over a given or defined.
area, and the cost of the concrete or filling employed, but as permitting the
caissoon to be more easily sunk or lowered, the side pressure being to some
extent lessened or relieved, and also as affording the means of rectifying to
some extent an error in the proper perpendicular sinking of the caissoon,
which can hardly be done at all with parallel caissoons, as they must follow the
precise direction in which the sinking is started, whereas my tapering caissoon
admits of a side pressure in any direction required, being effectively. employed

page_text: during the sinking against the top length or lengths; for although the ground
even at the surface may not perhaps be caused to yield against the pressure-
so exerted, yet its closing in or around the caissoon (as gradually sunk and
gradually offering continually smaller dimensions to or within the hole or
opening already made in the ground) may be so regulated as to be allowed to
take place more on one side or in one horizontal direction than another, or
possibly exclusively on one side, or in one direction, the side pressure to cause
this being given either directly from the side, or indirectly by unequal
loading.
The following Figures in Sheet No. 1 of the accompanying Drawings:
illustrate this part of my Invention. Figures A and B are a sectional elevation
and plan view respectively of a cast-iron caissoon of my improved construction
or manufacture, and Figure C an enlarged view of details of joint shewing
two lengths bolted together. In this instance the narrowing or tapering in
dimensions from the base upwards is shewn as effected by the several lengths
(vertically) secured one upon another, being themselves tapered and without
sets-off or steps. The Figures A*, B*, and C*, are similar. and corresponding
views respectively of a wrought-iron caissoon of my improved construction or
manufacture. Here also the several lengths are themselves tapered, but the
general tapering is also aided by a series of sets-off or steps at the joints. Or
instead of as represented, the several lengths may be cylindrical or uniform
in themselves but not of equal dimensions, and thus may form a step or set-off
at every joint or every second joint, or occasionally, as desired. Any of these
modifications may be adopted for either cast iron or wrought iron, the precise
form of jointing (represented) being altered, if needful, properly to adapt it;
to the construction and material employed. The dotted lines a, a, and b, b, in
Figures A and A*, are parallel to each other, and are introduced into the
Figures to shew the tapering of the caissoon the more clearly. The mode of
sinking the improved caissoons is the same as that for caissoons of ordinary
construction, but it is apprehended that the improved caissoons will be more
easily got down, and will in practice be found substantially equally firm in the
ground.
Secondly, my improved superstructure to be erected on the improved or
other foundations consists in combining into a structure by ties or struts, or
by both ties and struts, two or more compound columns or pillars of the
following specific character or features, the said columns not standing vertically
but being wider apart at the, base than above, and nearing each other,
reckoning from the base upwards, and in some instances uniting at the top,

page_text: for which purpose parts of the columns are removed, or are not required to
be constructed, so that they may lie and fit properly against each other: The
said character or features of the columns consists in their being constructed
with three or more principal ribs or vertebræ connected together with ties and
struts on the lattice principle on each face or side, so as to form lattice
columns with three or more sides.
From the above statement, and from the several Figures in the Drawings
herein-after referred to and description of them which follows, it will be noted
that the object sought by this part of my Invention is the construction of lofty
pyrimidical or tapering structures of wrought iron with a minimum or com-
paratively small quantity of material, and that I obtain this object by the use
or repetition of a great number of similarly formed pieces or detail members
which admit of much uniformity or repetition, or similarity of construction in
the manner of their being framed together to constitute the several lattice or
skeleton work, compound columns or pillars, or principal compound members
to be combined to constitute the pier or erection. With this object of
uniformity in view, and excepting as herein-after specified, I prefer to construct
'the said compound columns, pillars, or principal members with their vertebræ
not placed tapering or nearer towards each other at the top than at the
bottom, but placed generally parallel to each other (or as nearly as may be):
And it will be convenient herein-after in referring to the said compound
principal members when so constructed, to designate them as lattice prisms.
When combined however these lattice prisms or other compound columns will
stand or be placed and framed together not parallel to each other but tapering
towards or nearer to each other at the top than at the bottom. The economy
of material thus obtained will be manifest from the following considerations.
It is evident that the vertebrae will yield by bending rather than by crushing
under a superincumbent weight. If, then, a single piece of angle iron repre-
senting one of the vertebræ will (according to its scantling) bear a definite
weight upon an ascertained length without bending, it is also evident that the
several angle-iron vertebræ of a lattice prism will not yield if proportionately
to their number too great a weight be not superimposed, and bracing be
introduced at intervals to divide the several vertebræ into lengths not ex-
ceeding the said ascertained length. It is of course to be understood that a
margin of security should be allowed (as is usual in all structural works) to
compensate for the weakening of the material at the joints or connections of
the parts (unless specially strengthened), or for other contingencies; but
these remarks will sufficiently explain the economy above referred to, so far

page_text: as the individual lattice prisms are concerned, and it is evident that similar
considerations will. explain the economy of similar treatment in bracing
together the lattice prisms or other compound columns, pillars, or principal
members, to constitute a combined pier or erection.
I will now describe the several Figures in the Drawings which illustrate
this part of my Invention. In Sheet No. 2, Figures 1 and 2, are elevations
of two of the four sides of a lofty pier or erection, applied for carrying a
'railway bridge or viaduct, a small portion of which is indicated in the Figures
to explain the manner of the application. Figures 3 and 4 plans at bottom
and at top respectively; Figure 5 horizontal section at an intermediate height.
The lattice prisms, four in number, are distinguished by the capital letters,
HI, HI, (smaller reference etters being used for the details or pieces of which
they are framed or made up as herein-after described), these stand wide apart
at the base, and taper or approach each other gradually towards the top. I, I,
are wrought-iron girder-shaped stays, acting both as struts and ties rivetted to
the feet of the lattice prisms to space and hold them in position on plan.
Figure 6, shews a cross section of these stays on either of the lines 2* or 3*.
L, L, are short wrought-iron girder-shaped stays, rivetted to the top of the
Jattice prisms, and with horizontal plate serving to brace the structure at the top
and to distribute upon the several vertebræ (of the lattice prisms), herein-nfter
described the weight of the bridge or load carried. Figure 7 is a cross section
of the stays L on either of the lines 4* or 5*. M, M, are wrought-iron open-
work girders or horizontal struts, placed at the sides of the structures at
intervals or spaces in several positions between the bottom and the top. These
girder struts are conveniently formed (as shewn in Figures 8 and 9, herein-
after referred to) of angle-iron top and bottom members, the former straight,
the latter bellied or cambered to obtain increased depth at the middle, the two
being braced together diagonally, or as a triangular girder, by short flat bars
rivetted to them, and the top member, or the whole of the girder strut so
made being strengthened against lateral flexure, and to act efficiently as a
strut by a horizontal plate rivetted on which plate is also bellied or wider at
the middle than at the ends. I would remark here that in place of the girder
struts M, as described, any other convenient construction of strut, whether of
wrought iron or cast iron, may be used if preferred. N, N, are short tie bars
for horizontally bracing the girder struts M to the lattice prisms, as shewn in
Figure 5, and more in detail in the said Figure 9. 0,0, are diagonal ties on
each of the outside faces or sides of the structure, serving to brace its several
lattice prisms together vertically, or as nearly so as they stand. 0*, 0*, are

page_text: angle-iron bars, acting both as struts and ties on two of the said outside faces
or sides situate at the upper portion where the lattice prisms more closely
approach each other, and used in place of the ties O and girder struts M,'
employed in other parts of the structure. The construction of the lattice
prisms is as follows, the square form (on plan), as represented, being that
which I prefer :-Figure 8 is an elevation on a larger scale of a portion of
one of these, and Figure 9 a plan view to correspond, both Figures shewing
also in detail the girder struts M, and the method of jointing or connecting
together the strut and tie portions of the bracing of the combined structure
already described. h, h, h, h, are four principals, ribs, or vertebræ, each
consisting of lengths of angle iron butting together at the ends, being properly
faced at the ends where they butt, and being jointed with cover pieces as at
(see Figure 9*). As arranged, the vertebræ present four faces or sides of a
skeleton pillar, each of which is braced by angle-iron lattice bars h*, which
act both as ties and struts. The Figure 10 represents (on a different scale) a
short length or portion of a lattice prism as if its four sides were developed or
unfolded, and is introduced to shew not only that each side is alike, but that
where the angle iron is pierced for rivetting to the lattice bars it is at any one
spot or position so pierced only on one side or table of the angle iron and not
on both of them, and is therefore not unnecessarily weakened or injured by
the piercing. If, however, it should for any reason be preferred, the dis-
position of the lattice bars may be such as to sacrifice this consideration, as in
the lattice prism represented by Figure 11, and the development of the same
by Figure 12, in which Figures the lattice bars are shewn as crossing each
other. In this case horizontal double angle-iron or cast-iron struts h³ are
introduced, and the lattice bars h* being only required as ties and not as
struts are formed of flat bar iron instead of angle iron. It may be noted
in respect of the firstly described construction of prism that the lattice bars of
two opposite sides or faces, as seen in connection, would present the appear-
ance of crossing each other, but that in the Drawing such crossing has been
purposely omitted, as it has been considered preferable in illustration of the
construction to represent only the front side or face, without shewing through
its openings the bars of a side or face behind the front. And I would also
remark that any other approved disposition or method of lattice bracing may
be adopted; and further, that although for the sake of uniformity of con-
struction, and particularly so when four columns are employed in the combined
structure, I prefer to construct the columns H as lattice prisms; yet if
desirable under any particular circumstances they may be constructed with

page_text: their vertebrae tapering or nearing each other towards the top instead of
parallel to each other, and in such case not strictly constituting lattice prisms
as herein above defined, but nevertheless properly braced together to constitute
the combined pier or erection. Specially for piers or erection's intended for
situations where no very great or extreme altitude is demanded, or where less
weight may have to be supported, it will be found convenient to modify the
general construction above described to that represented in Figures 13, 14,
and 15, 16 (see Sheet No. 1), being two elevations and two plans respectively
"corresponding with each other, shewing two columns H employed instead of
four in the combined structure, the said columns not being lattice prisms, but
nevertheless formed each with four vertebra to form the skeleton or outline of
a figure, in which on two of the sides or faces the vertebræ are parallel to
each other; and on the other two they are not so, but are wider apart at the
base than at the top so as not only to present a better appearance than if
parallel, but giving a better or wider footing upon which to stand. The
bracing of the columns and of the combined structure may be either as
represented or may be modified as described in reference to piers or erections,
with four columns as herein above described, or in any way within the limits
of the Invention as herein above set forth. The Figure 17 (see Sheet No. 2)
illustrates that portion of the definition of the Invention in which the columns
are described as in some instances uniting at the top. It will be noted that
where one column would overlap another the prismatic or regular form is
dispensed with and the parts made to lie and fit properly against each other,
th vertebra h being however continued to the top and connected by girders
or stays, so as properly to receive and distribute the weight. For sheer legs
two, and sometimes three or more of the improved compound columns or
pillars may be employed properly braced together, and for lighthouses three or
larger number may be employed, also properly braced together. Possibly
"three vertebrae to each column or pillar will be found convenient in these
cases, or more particularly in the case of lighthouses, or in any case where a
large number of pillars might be desirable. When three vertebræ only are
employed in the column they may conveniently consist of angle iron rolled to
an angle of sixty degrees; and generally it may be stated that the vertebræ
may be of any approved sectional form.
I would further remark that my Invention affords a convenient mode of
erecting portable builders' hoists, the parts, or some of them for the conve-
nience of transport being made to bolt together, instead of being rivetted as
for normanent structures.
!
"

page_text: And lastly, I would remark that the bridges represented in the Drawings
as supported by my improved piers or erections form no feature of the Inven-
tion, and are introduced solely to illustrate one and an important manner in
which it may be applied.
In witness whereof, I, the said Charles de Bergue, have hereunto set
my hand and seal, this Fourth day of December, in the year of our
Lord One thousand eight hundred and sixty-five.
C. DE BERGUE. (L.S.)