IMPROVEMENTS IN THE
Year: 1853

page_text: LETTERS PATENT to John Macintosh, of Pall Mall, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN THE CON-
Sealed the 7th December 1858, and dated the 3rd August 1853.
PROVISIONAL SPECIFICATION left by the said John Macintosh
at the Office of the Commissioners of Patents, with his Petition,
on the 3rd August 1853.
I, JOHN MACINTOSH, of Pall Mall, in the County of Middlesex, do
hereby declare the nature of the Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF BRIDGES, VIADUCTS, AND OTHER LIKE STRUCTURES" to be
as follows:-
This Invention consists of combining a series of bow and string
arches into one girder or beam in such manner that each bow or arch
springs from the crowns of the two bows, or arches to which it is con-
nected. And in constructing and repairing arches, particularly in rivers
and waterways, in place of having piers and foundations, and springing
the arches from and supporting the arches by such piers, inverted metal
arches are used to support the arches above.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Macintosh in the Great Scal Patent
Office, on the 2nd February 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MACINTOSH, of Pall Mall, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of August, in the year of
our Lord One thousand eight hundred and fifty-three, in the seven-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Macintosh, Her special licence
that I, the said John Macintosh, my exccutors, administrators, and
assigns, or such others as I, the said John Macintosh, my executors,
administrators, and assigns, 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
THE CONSTRUCTION OF BRIDGES, VIADUCTS, AND OTHER LIKE STRUCTURES,"
upon the condition (amongst others). that I, the said John Macintosh,
by an instrument in writing under my hand and scal, should parti-
cularly 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 Macintosh, 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 (that is to say):
This Invention consists of combining a series of bow and string
arches into one girder or beam in such manner that each bow or arch
springs from the crowns of the two bows or arches to which it is
connected. And in constructing and repairing arches, particularly in
rivers and waterways, in place of having piers and foundations, and
springing the arches from, and supporting. the arches by such piers,
inverted metal arches are used: to support the arches above.

page_text: Having thus stated the nature of my Invention, and the manner
of performing the same, I will now proceed to give a more detailed
account thereof, and refer to the accompanying Drawings in the various
Figures of which the same letters in all instances indicate similar parts.
DESCRIPTION OF THE DRAWING A.
Figure 1, is a side elevation of a bridge constructed in accordance
with my Invention. a, a, a, are a scries of bows having their extremities
tied in by rods b, b, as shown. c, c, c, is an upper tier of bows having
their bearing upon the crowns of the arches or bows a, a, to which
they are firmly fixed in such manner as to form a strong girder: the
roadway c, is suspended by rods d, d, or otherwise to the bows a, a, c,c,
as shewn.
DESCRIPTION OF THE DRAWING B.
Figure 2, is a side clevation of another form of bridge constructed
according to my Invention. The bows a, a, having strings b, b, are con-
nected together and to vertical supports c, c, and the roadway e, e, is
supported or laid on the crowns of the bows a, a; the vertical sup-
ports c, c, are at their lower ends connected together by inverts dl, d,
which lie at the bottom or bed of the river or other.stroam suitably
prepared to receive them; by this means I am enabled to construct;
bridges without the necessity of forming coffer dams; and the inverts
may be temporarily tied with strings b, b, similar to those of .the
bows a, a, and the ends closed water-tight so as to float the parts to
their destination, and then to remove the water-tight ends and sink the
parts to the bed or bottoni of the river or other channel over which the
bridge is to be constructed. The several portions of the bridge each
being formed of the parts a, b, c, d, are, after being sunken to the bed
of the river and properly set in position, to be firmly secured together,
after which the roadway and side railing are to be placed and affixed,
as usual, and the strings b, of the bows a, and inverts d, may then be
removed so as to allow of the full dimensions of the arch formed by the
bows a, and inverts d, being clear for the passage of traffic.
DESCRIPTION OF THE DRAWING C.

page_text: the Drawing A, I in this instance connect bows as shown, the one
being invert to the other, firmly connected together at their ends, and
strings or tie rods may be placed across to stiffen the parts during the
floating of them to their destination, after which and the filling in of
the masonry, &c., at e, f, and the bed of the river at g, will be then
sufficient to prevent the bows a, and inverts c, from becoming displaced.
The materials to be used in the construction of the bows and inverts
and supports may be of iron or wood or iron and wood combined,
according as the dimensions or span of the bridge requires.
DESCRIPTION OF THE DRAWING D.
Figure 4, shows a side view of a bridge of somewhat different form
to either of the above described, in which the rods i, i, from the
bows a, a, are made to sustain a road or footway bridge, in which casc
the bridge above at h, may be a railway bridge or suitable for any other
purpose, & the bridge below being suspended therefrom by rods i, i,
as shewn, may be a roadway or footway bridge, or both, as desired.
Having thus described my Invention, and the best means which which I
am acquainted for carrying the same into practice, I wish it to be under-
stood that I do not intend to confine myself to the precise details given,
as the same may be varied without departing from my Invention; but
what I claim is, the modes herein described of constructing bridges by
forming and connecting bow and string arches into girders or beans.
I also claim the constructing and repairing arches without the ordinary
abutnients by using inverts as herein explained.
In witness whereof, I, the said John Macintosh, have hereunto
set my hand and seal, this Twenty-eighth day of December, in
the year of our Lord One thousand eight hundred and fifty-three.
Witness,
FRED HARRIS.
JOHN MACINTOSH. (L.S.)