AN IMPROVED METHOD OR METHODS OF ARRANGING AND COMBINING CERTAIN MATERIALS USED IN CONSTRUCTING HOUSES, BRIDGES, AND OTHER BUILDINGS, WHEREBY GREATER STRENGTH ARD DURABILITY WILL BE OBTAINED
Year: 1835

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
WITTY, of Stoke-upon-Trent, in the County of Stafford, Civil Engineer, send
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Third day of December, One thousand eight hundred and
thirty-five, in the sixth year of His reign, did, for Himself, His heirs and
successors, give and grant unto me, the said Richard Witty, His especial
license, full power, sole privilege and authority, that I, the said Richard Witty,
my exors, adiiors, and assigns, or such others as I, the said Richard Witty,
my exors, adñiors, 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,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "AN IMPROVED
METHOD OR METHODS OF ARRANGING AND COMBINING CERTAIN MATERIALS USED IN
CONSTRUCTING HOUSES, BRIDGES, AND OTHER BUILDINGS, WHEREBY GREATER STRENGTH
ARD DURABILITY WILL BE OBTAINED;" in which said Letters Patent is contained
a proviso that I, the said Richard Witty, shall cause a particular description
of the nature of my said Invention, and in what manner the same is to bo
performed, to be inrolled in His said 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Richard Witty, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly set forth in

page_text: the following description thereof, and in the Drawings illustrative thereof in
the margin hereof, that is to say:-
The first of my said improved methods of arranging and combining certain
inaterials used in constructing houses, bridges, and other buildings, is founded
on this acknowledged general principle in mechanics, that the strength of a
beam of wood or bar of metal laid horizontally on supports at each end, is as
the square of its depth, multiplied by its breadth and divided by its length,
and on this practical deduction from that a number of thin plates or lamina of
wood or iron when placed together edgewise will bear considerably more
weight than the same quantity of wood or iron in the form of a solid beam or
bar. Hitherto but little advantage has been taken in building of this property
of lameller combinations, owing to the great tendency of thin plates of wood
or iron to deflect laterally when pressed upon by heavy weights, and to the
.great difficulty of so binding together any number of such plates as to prevent
that deflection taking place. Now by my said first-improved method this
tendency of thin plates of wood or iron to deflect laterally is effectually coun-
teracted, and the superior strength of. lamellar .combinations is rendered
universally available. for building and other constructive purposes. Plates of
lamina combined according to this method may consist entirely of wood
or entirely of iron, but I prefer wood and iron combined in the manner
following, as uniting greater strength and durability: I first take several
sheets of rolled iron and place these together edgewise, being governed
as to the number of the said sheets, and the width, length, and thickness
tliercof, by the degree of strength required in each particular case; I then
insert between every two of these iron plates one of oak, larch, fir, or other
wood of at least twice the thickness-of-the-iron plates, and this done, Ipin or
bolt the whole securely together, so as to form them.into.onc compound beam
'or bar. The two outer iron plates are chosen of greater thickness than the
Frest, in order that they may the better sustain the pressure of the pins or bolts
and resist the lateral deflecting tendency of the plates. When the beam or
bar is required to be of greater length than the length of the individual plates
of which it is compounded, plates of the same or of different lengths are so
arranged that not any two ends of these plates shall coincide, and the fastening
pins or bolts are inserted at the different points of junction, by which means
this further advantage is obtained, that beams or rods possessed of that superior
strength which belongs to lamellar combinations, may be compounded of any
required depth and length.
Figure 1 of the Drawings in the margin hereof represents a plan of a beam
or rod formed in the manner just described, in which all the plates.or lamina

page_text: are of the same length, and Figure 1, a plan of a beam or bar in which all
the plates are of different lengths.
:
The second of my said improved methods is subsidiary to the first, and
consists in girding, trussing, or supporting laminated beams or rods compounded
as aforesaid, in such manner that floors, roofs, roadways, and other architectural
and engineering constructions, may be made to sustain much greater weights
with considerably less material than can be done by any of the methods of
girding or trussing now commonly followed. Instead of employing for girders
straight or irregular-shaped rods or bars, I make use of regularly formed iron
segments of circles or segmental hoops, secured at the ends in manner herein:
after described. The beam forms the chord line to the segment of the circle
or segmental hoop or girder. The versed sine may be of any depth, but I
prefer that the segments should be arcs of large circles with versed sines
of not less than one inch for every three feet of the length of the beam or
chord line.
Figure 2 of the Drawings in the margin hereof represents a trussing of this
description. A is the lamellar beam, &e. ; B, the iron segment or hoop applied
to the under part of the said beam, and secured to it at the ends by the nuts
and screws C, C; D, D, D, D, D, are blocks or stays of hard wood or cast
iron, inserted at regular intervals in the space between the chord line and iron
segment, care being taken to adapt these blocks or stays very exactly to
the variations in the curve of the segment. By turning the ends or screws
C, C, the blocks or stays D, D, D, D, D, are pressed upwards against
the beam A, and the whole bound so firmly and intimately together that
the transverse strain is equally distributed over the entire mass; and tho
beam will sustain equally throughout its length any weight that may be
placed upon it.
To shew more clearly the manner of following out my said two improved
methods of structural arrangement and combination in their various practical
applications, and to enable ordinary. workmen to apply them with facility,. I
have added the illustrative Figures in the margin hereof, marked: 3, 4, 5, 6, 7,
and I now proceed to describe the same.
Figure 3 is a working Diagram, intended to shew in what manner the
curve most proper to be given to the iron sigment or hoop is to be formed.
Suppose the length of the beam, joist, rafter, or spar A, A, which is to serve
as the chord of the arc, is twenty-four feet, and that the versed sine D of the
iron segment B, B, is two feet, then, in order to ascertain the diameter of
the circle corresponding to that segment, the rule is, to add the sum of the
squares of half the length of the beam or chord line (12x12=144) to the

page_text: square of the versed sine (2×2=4), and divide the amount (148) by
the versed sine (2), when the quotient (74) will be the diameter of a circle
corresponding to the iron segment or iron hoop, and the half of this quotient
will be the radius of the iron segment or hoop itself. I prefer the arc of a
circle to an arc of any other curve for the iron segment or hoop, as being
stronger than any other, and at the same time more easily formed; and
although I sometimes employ a segmental hoop formed of iron chain or
горе,
I prefer in most cases strong hoop iron or bar iron carefully bent into
the curvilineal form required, with an additional thickness at the ends where
the nuts or screws are inserted.
Figure 4 represents a bridge constructed according to my improved methods.
A, A, is the laminated beam, which forms the balustrade, with ornamental
railing at top; B, B, the segmental hoop secured to the ends of the
beam A, A; D, D, the pillars or piers; E, E, the roadway.
Figure 5 represents a railway similarly constructed. A is a laminated
beam, resting on a solid embankment D, and B, B, two other laminated
beams of greater thickness or depth than A, because of their crossing the
valley C, C, and resting only on the pillars G, G, G; F, F, are the segmental
hoops or ties secured to the ends of the beams B, B, with their stays c, c-e, c.
The beams may either serve as sleepers to lay edge or plain rails upon, or
either sort of rail may be combined with the beams themselves in the original.
construction thereof.
Figure 6 represents a roof constructed according to my said improved
methods. A, A, are the principal spars, with segmental hoops and stays;
B, B, purlins, with ditto; C rods of iron, which are carried across the foot of
the roof, and through each wall plate, in order to tie the roof together. The
main beam, king posts, and other cumbrous appendages of ordinary roofs are
by this means wholly dispensed with.
Figure 7 is a representation of a common floor constructed on the same
principles. A, A, are the walls of the building; B, B, the joists; C, C, the
segmental hoops carried through and underneath the joists; D, D, the
floor.
Figure 8 represents a compound floor constructed according to my improved
methods, but without joists for either floor or ceiling. A is the floor, the
boards being arranged diagonally one upon another; B, one of a series of
segmental hoops, stretching underneath the floor, and fastened to the wall
plates; C, C, and D, D, the stays.
And having now particularly described the nature of my said invented
improvement, and the manner in which the same are performed, I declare
:

page_text: that I do not claim any of the articles or things herein-before described
separately or otherwise, than and in so far as the same are newly com-
bined and arranged for the purposes aforesaid; and I declare that what
I claim as my Invention is the method herein-before described of combining
a number of plates of wood and iron, or of wood alone, or iron alone, into
one lamellar beam of greater strength than any solid beam containing the
same quantity of material, and also the method herein-before described of.
girding, trussing, or supporting such lamellar beams or joists, or rafters
or spars, by means of segmental arcs or hoops; and such my invented
improvements being, to the best of my knowledge and belief, entirely new,
and never before used within that part of His said Majesty's United Kingdom
of Great Britain and Ireland called England, His said Dominion of Wales,
or Town of Berwick-upon-Tweed; and that I do verily believe that this my
said Specification doth comply, fully and without reserve or disguise, with the
proviso in the said herein-before in part recited Letters Patent contained,
wherefore I hereby claim to maintain exclusive right and privilege to my
said Invention.
In witness whereof, I, the said Richard Witty, have hereunto set my
hand and seal, this Twenty-eighth day of May, in the year of our
Lord One thousand eight hundred and thirty-six.