CERTAIN IMPROVEMENTS IN THE MANUFACTURING AND CON- STRUCTION OF A WROUGHT OR MALLEABLE IRON RAILROAD OR WAY
Year: 1820

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BIRKINSHAW, of Bedlington Iron Works, in the County of Durham, Gentleman,
send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did,
by His Letters Patent under the Great Seal of that part of the United
Kingdom of Great Britain and Ireland called England, bearing date at West.
minster, the Twenty-third day of October, in the first year of His reign,
give and grant unto me, the said John Birkinshaw, my exors, admors,
and assigns, His especial licence, full power, sole privilege and authority,
that I, the said John Birkinshaw, my exors, admors, and assigns, during
the term of years therein mentioned, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, and also in all. His Majesty's Colonies and Plantations abroad,
my Invention of "CERTAIN IMPROVEMENTS IN THE MANUFACTURING AND CON-
STRUCTION OF A WROUGHT OR MALLEABLE IRON RAILROAD OR WAY; in which said
Letters Patent there is contained a proviso that if I, the said John Birkinshaw,
shall not particularly describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, by an instrument in writing.
under my hand and seal, and cause the same to be inrolled in His Majesty's
High Court of Chancery within two calendar months next and immediately.
after the date of the said Letters Patent, that then the said Letters

page_text: Patent, and all liberties and advantages, whatsoever thereby granted, shall
utterly cease, determine, and become void, as in and by the same, relation
being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Birkinshaw, do hereby declare that the nature of my.said Invention,
and the manner in which the same is to be performed, are particularly
described and ascertained in and by the Drawings hereunto annexed, and the
following description thereof (that is to say):-"
My Invention consists in the adaptation of wrought or malleable iron bars or
rails of a peculiar form instead of cast-iron rails, as heretofore. From the brittle
nature of cast iron it has been found by experience necessary to make the bars
of a railroad sufficiently strong to bear at least six times the weight
intended to be carried along the road, by which the original cost of
a railroad was considerably augmented, or if light rails were used the necessity
of frequently repairing entailed a heavy expence upon the proprietors. To
obviate these objections I have invented a bar to be made of wrought or
malleable iron, the original cost of which will be less than the ordinary cast-
iron bars or rails, and at the same time will be found to require little (if any)
reparation in the course of many years. The rails or bars which I have
invented are: formed as prisms,-though their sides need not of necessity be
flat.
Figures 1 and 2. of. the Drawings, annexed slew sections of the bar thus
formed. A is the upper surface upon which the wheel of the carriage is to
run, slightly convex.in.order to reduce the friction, and B is the under part
which rests in the supporting blocks, chairs, rests, standards,, or pedestals
mounted upon the sleepers. The wedge form is proposed because the strengtli
of the rail is always in proportion to the square of its breadth and depth, hence
this: form possesses all the strength of a cube equal to its square, with only
half the quantity of metal, and consequently half the cost. Sufficient strength,
however, may be still retained, and the weight of metal further reduced, by
forming the bars with concave sides, as shewn in section Figure 3 and 4.
Indeed. Fig. 3. is the form of bar which of all others I prefer for the con-
struction. of railroads, though the prism or wedge form in all its varieties I
claim as being the principle upon which my Patent right is founded. The
mode of making these wedge-formed rails of malleable iron is by passing bars
of iron when heated through rollers having grooves or indentations cut upon
their periphery agreeable to the intended shape of the bar to be produced, a
pair of which rollers are shewn at Figure 5.
Though I recommend and adopt this method as the most eligible means of

page_text: producing my malleable iron rails, yet I do not claim the Invention of this
mode of of operating upon bars by which they are moulded into any shape,
but confine my claim to the exclusive right of manufacturing and vending the
wedged-formed bars or rails of malleable iron of any length for the purpose
of forming or constructing railways or railroads.
The advantages of my improved wrought-iron railroads are,-
First, on the ground of economy, their original. cost being less than the
ordinary cast-iron rails.
Secondly, that the respective rails may be made of considerable length
(18 feet I should recommend), by which the inconvenience of so many joints
is reduced, and consequently the shocks or jolts to which the carriages are
subject in passing over the joints (very much to the injury of the machinery)
is also diminished.
And in order still further to remedy the evil arising from the joint of the
railroad, I propose to weld the ends of the bars together as they are laid down,
so as to form considerable length of iron rail in one piece.
In witness whereof, I, the said John Birkinshaw, have hereunto set my
hand and seal, this Second day of December, in the year of our Lord
One thousand eight hundred and twenty.
CUTHB W ERRINGTON.
AND BE IT REMEMBERED, that on the Second day of December, in the
year of our Lord 1820, the aforesaid John Birkinshaw came before our said
Lord the King in His Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stampt according to the
tenor of the Statutes made for that purpose.