A NEW AND PECULIAR ART OR METHOD OF CONSTRUCTING BRIDGES OF PLATE IRON, EITHER WROUGHT, CAST, FRAME, OR PUT TOGETHER SO AS TO FORM HOLLOW BODIES, MASSES, OR CUBES, CAPABLE OF BEING FILLED UP WITH EARTH, SAND, STONE, GRAVEL, OR OTHER MATERIALS TO MAKE THE SAME SOLID BODIES, MASSES, OR CUBES, OR NOT BEING FILLED. HAVE THE SEMBLANCE OF SOLID BODIES MASSES OR CUBES
Year: 1797

page_text: NASH'S SPECIFICATION.
TO ALL TO WHOM THESE, PRESENTS SHALL COME, I, JOHN
NASH, late of Duke Street, in the Parish of Saint James, in the County of
Middlesex, but, now of Dover Street, in the said Parish and County, Architect,
send greeting.
..
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters. Patent under the Great Seal of Great Britain, bearing date.
the Seventh day of February, in the thirty-seventh year of His reign, give
and grant unto me, the said John Nash, His special licence, full power, sole
privilege and authority, that I, the said John Nash, 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
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A NEW AND PECULIAR ART OR METHOD OF CONSTRUCTING BRIDGES OF PLATE
IRON, EITHER WROUGHT, CAST, FRAME, OR PUT TOGETHER SO AS TO FORM HOLLOW
BODIES, MASSES, OR CUBES, CAPABLE OF BEING FILLED UP WITH EARTH, SAND, STONE,
GRAVEL, OR OTHER MATERIALS TO MAKE THE SAME SOLID BODIES, MASSES, OR CUBES,
OR NOT BEING FILLED. HAVE THE SEMBLANCE OF SOLID BODIES, MASSES, OR CUBES;"
in which said Letters Patent there is contained a proviso, obliging me, the
said John Nash, by an instrument in writing under my hand and seal, to
particularly describe and ascertain the nature of my said Invention, and in
what manner the same is to be performed, and cause the same to be inrolled
in His Majesty's High Court of Chancery within one calendar month next
and immediately after the date of the said Letters Patent, as in and by the
said Letters Patent, reference being thereunto had, may more fully and at
largo appear.
L
2
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Nash, do hereby declare that the nature of my said Invention of a

page_text: new and peculiar art or method of constructing bridges of plate iron, either
wrought, cast, framed, or put together so as to form hollow bodies, masses, or
cubes capable of being filled up with earth, sand, stone, gravel, or other
materials to make the same solid bodies, masses, or cubes, or not, being filled,
have the semblance of solid bodies, masses, or cubes, and the manner in which
the same is to be performed, is particularly described and ascertained in the
manner following (that is to say) :-
The arch of the bridge is formed by hollow frames or boxes, each box
consisting of four sides and a bottom. The sides form the arch joints of the
bridge, and are diminished so as to tend to the. centre of the circle, which
strikes the arch in such a manner that when these boxes or frames are put
together side by side they form the arch of the bridge, the joints of which
have a solid bearing throughout, like those of stone bridges. These boxes are
afterwards filled with earth, clay, or sand, or gravel, or gravel mixed with
lime, or sand mixed with lime, or rough stone, or rough stone masonry or
bricks, or freestone, or any other substance, so that when filled the arch is
one body, cased with iron. These boxes may be of cast iron or wrought iron,
Ir ay be cast, rolled or hammered in flat plates and frames, and put together.
They may be cast without bottoms, and the bottoms put in, as shewn in the
section A, in Drawing No. 1, hereunto annexed, or they may be cast with
bottoms, as in the section B in the said Drawing No. 1, or they may be used
without bottoms, or filling up and be boarded or plated over at top, and the road
filled in, as in section C in the said Drawing No. 1; one part of the principle
of this Patent being the abuttal of plates of iron throughout the breadth of
the bridge in the manner of the arch joints of a stone bridge; or those boxes
may be a succession of arches with flanches forming the arch joints, as in
section D, in, Drawing No. 2, also hereunto annexed, and filled up in the
spandrils or not filled up, or they may be formed of hollow cylinders with
flanches, as in the section E, in the said Drawing No. 2. These arch joints
may have sheet lead or other composition placed between them to fill up the
uneven surfaces of the iron to prevent the pressure of iron against iron. The
arch joints or flanchings may be screwed together, as in section A, in the said
Drawing No. 1, or stubb tenants or fillets, with correspondent holes, mortices,
and grooves, may be cast in the plates themselves, and fitted into each other,
as in the section B.in said Drawing No. 1. The skirting or kirb which
keeps in the ground may be cast or framed with the boxes, as in the
section F in the Drawing No. 1, also. hereunto annexed, or may be cast
separate and put on, or may be omitted. When two, three, or more arches are
put together, the spandrils or spaces between the arches are formed by hollow

page_text: spandrils of wrought iron or cast iron, and framed, cast, or put together as
before mentioned, and may or may not be filled up solid as the boxes of the
arches before described. These hollow spandrils may be cylindrical, trian-
gular, quadrangular, or of many sides, as represented by the Figures
G, H, I, K, &c. in the Drawing No. 2, also hereunto annexed. The piers of
these bridges are formed, like the boxes, hollow, and may be filled up solid
or otherwise, and may be of plate iron, either wrought or cast, and framed or
put together, or they may be cast in one piece, may be in form cylindrical,
triangular, quadrangular, or of many sides, as in the sections L, M, N, O, in the
Drawing No. 3, also hereunto annexed. They may be cast with the hollow
frame forming the piers, or be fastened to them, as in the Figures P, Q, in the
Drawing No. 3, also hereunto annexed. The dam is also formed hollow by
piles of plate iron grooved, rebated, and dovetailed into each other, which,
when fixed into each other, form a hollow box, and when driven or inserted
into the bed of the river form a dam for the pier, as in Figure R, and wher.
the pier is built are driven home into the bed of the river, make a box of
dovetailed piles enclosing the ground on which the pier stands, and securing
it from being undermined by the water passing through the arch.
In witness whereof, 1, the said John Nash, have hereunto set my hand
and seal, this Sixth day of March, in the year of our Lord One
thousand seven hundred and ninety-seven.
In the presence of
W. T. HEARTWELL, Public Office.
JOHN EDWARDS, New Inn.
AND BE IT REMEMBERED, that onethe same Sixth day of March, in
the year above mentioned, the aforesaid John Nash came before our Lord the
King in His Chancery, and acknowledged the Specification aforesaid, and all
and every thing therein contained, in form above written. And also the
Specification aforesaid was stamped according to the tenor of the Statute in
that case made and provided.
Inrolled the same Sixth day of March, in the year above written.