IMPROVEMENTS IN THE MANU- PACTURE OF TUBULAR BRIDGES, PART OF WHICH IMPROVEMENTS IS APPLICABLE ALSO TO THE PREPARATION OF PLATES FOR COVERING IRON SHIPS, FOR CON- STRUCTING BOILERS, AND FOR OTHER ANALOGOUS USES
Year: 1854

page_text: LETTERS PATENT to John Getty, of Liverpool, in the County of Lan-
caster, Ship Builder, for the Invention of "IMPROVEMENTS IN THE MANU-
PACTURE OF TUBULAR BRIDGES, PART OF WHICH IMPROVEMENTS IS APPLICABLE
ALSO TO THE PREPARATION OF PLATES FOR COVERING IRON SHIPS, FOR CON-
STRUCTING BOILERS, AND FOR OTHER ANALOGOUS USES."
Scaled the 4th April 1854, and dated the 23rd January 1854.
PROVISIONAL SPECIFICATION left by the said John Getty at the Office of
the Commissioners of Patents, with his Petition, on the 23rd January
1854.
I, JOHN GETTY, of Liverpool, in the County of Lancaster, Ship Builder, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF TUBULAR BRIDGES, PART OF WHICH IMPROVEMENTS IS APPLICABLE
ALSO TO THE PREPARATION OF PLATES FOR COVERING IRON SHIPS, POR CONSTRUCTING
BOILERS, AND FOR OTHER ANALOGOUS USES," to be as follows:-
This Invention relates, firstly, to certain means for facilitating the marking
of the parts for the bolt-holes in the plates employed in constructing tubular

page_text: bridges; and, secondly, to a mode of determining the shape to which plates,
whether employed in constructing bridges, ships boilers, or other metal
work are required to be cut to fit the space which they are destined to
оссиру.
In carrying out the first part of this Invention I provide frames equal in
length to the length or the breadth of the plate to be marked, and sufficiently
wide to carry a strip of strained paper or cloth which will cover a double line
of bolt-holes.
Having applied this frame to a double line of holes in an adjoining plate, I
mark on the paper or cloth with chalk or other material applied through the
bolt-holes, and where these marks occur I cut out holes in the cloth or paper,
and thereby form a template, which will guide me in punching the holes
through the plate of iron. In order to ascertain the position of the holes in
the metal ribs or stays, (where such occur,) I use a separate frame, or form this
frame of a capacity equal to the size of the plate to be fitted. In either case
I provide the frame along its length and breadth with fixed or removeable
pins, and stretch across the frame and over these pins a chalked string, so
as to cut the line of centres of the rows of holes, and then at right angles to
these lines I stretch a length of chalked string, so as to cut the centres
By pressing therefore the intersections of the strings
on the plate to be pierced the centres for the bolt-holes will be marked
thereon.
of the individual holes.
Or in lieu of the frame and paper I may employ stiff' pasteboard or other
board capable of receiving studs, which when the board is applied to the place
destined for the pierced plate are stuck into the board in positions exactly
corresponding to the bolt-holes in the adjacent plates and ribs or stays, and
thus a template is formed from which an impress of the bolt-holes may be
made on the plate to be pierced.
Another improvement which I propose to effect by the use of templates is,
the manufacture of metal plates (by one shearing operation) to the proper size
and shape which they are required to take. Thus, supposing I am building a
ship, I take a light frame somewhat larger in capacity than the plates to be
used, and having stretched upon it a sheet of paper or cloth, or other analogous
substance suitable for receiving the marks for the bolt-holes, I apply it to the
ship; and besides marking the situation of the bolt-holes thereon I draw the
shape required for the plate, which shape will be determined according to
the "shear" of the ship. I then cut the paper to these lines, and the iron
plate manufacturer being furnished with such template, besides punching out

page_text: the holes, can cut the iron plate (taking it in its irregular form as it leaves the
rolls) in the form required for use, by which means the laborious and useless
operation of bringing the plates to a uniform shape suited for the market will
be avoided.
This improvement it will be obvious is applicable to the manufacture of
metal plates for many other purposes besides bridge and ship building.