IMPROVEMENTS IN THE FABRICATION OR MANUFACTURE OF STEEL
Year: 1858

page_text: LETTERS PATENT to Sir Francis Charles Knowles, of Lovell Hill, in the
County of Berks, Baronet, for the Invention of "IMPROVEMENTS IN THE
FABRICATION OR MANUFACTURE OF STEEL."
Sealed the 14th December 1858, and dated the 15th June 1858.
PROVISIONAL SPECIFICATION left by the said Sir Francis Charles
Knowles at the Office of the Commissioners of Patents, with his Petition,
on the 15th June 1858.
I Sir FRANCIS CHARLES KNOWLES, of Lovell Hill, in the County of Berks,
Baronet, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE FABRICATION OR MANUFACTURE OF STEEL," to be as follows:-
The nature of my improvements herein is as follows:-As soon as the
metal is withdrawn from the converting furnace, in whatever shape it may be,
as bars, rods, sheets, plates, &c., I put it into retorts of proper form and
dimensions, but without any charcoal or other carbonaceous matter, and I
carefully exclude all atmospheric air from such retorts after they are filled
with the metal. The retorts, with their contents, are then heated in the
ordinary way of gas retorts for a longer or shorter time, according to the size
or thickness of the bars, rods, plates, &c., until the "temper" or cementation
by the carbon shall have become even throughout the mass, and the steel itself
almost homogeneous. The bars, &c. must then be drawn out, and imme-
diately covered up from the air with the siftings of coke, and allowed to cool
gradually in the heap.

page_text: I treat ingots of steel in the same manner, in order to render them more
homogeneous, and to destroy any crystallization or state of strain in the mass
among its molecules. If bars, rods, plates, &c. of steel, after conversion,
(above all, if the iron from which they are made be itself clean,) and after this
subsequent process in retorts be submitted to what is called a "washing"
heat, and then hammered or rolled, "shear" steel or steel analogous to it,
may be made without any welding process, and will be found to be highly
homogeneous and solid. Ingots so treated will be less liable to crack under
the hammer.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Sir Francis Charles Knowles in the Great Seal Patent Office
on the 15th December 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Sir FRANCIS
CHARLES KNOWLES, of Lovell Hill, in the County of Berks, Baronet, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of June, in the year of our Lord One,
thousand eight hundred and fifty-eight, in the twenty-first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Sir Francis Charles Knowles, Her special licence that I, the said Sir Francis
Charles Knowles, my executors, administrators, and assigns, or such others
aş I, the said Sir Francis Charles Knowles, 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 Inven-
tion for "IMPROVEMENTS IN THE FABRICATION OR MANUFACTURE OF STEEL," upon
the condition (amongst others) that I, the said Sir Francis Charles Knowles,
my executors or administrators, by an instrument in writing under my or
their, or one of their hands and seals, should particularly describe and ascer-
tain 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 Sir Francis Charles Knowles, do
hereby declare the nature of my said Invention, and in what manner the

page_text: same is to be performed, to be particularly described and ascertained in
and by the following statement thereof, that is to say:-
The nature of my improvements herein is as follows:-As soon as the metal
is withdrawn from the converting furnace, in whatever shape it may be, as
bars, rods, sheets, plates, &c. I put it into retorts of proper form and dimen-
sions, but without any charcoal, or other carbonaceous matter, and I carefully
exclude all atmospheric air from such retorts after they are filled with the
metal. The retorts, with their contents, are then heated in the ordinary way
gas retorts, for a longer or shorter time, according to the size or thickness
of the bars, rods, plates, &c., until the "temper" or cementation by the carbon
shall have become even throughout the mass, and the steel itself almost homo-
geneous. The bars, &c. must then be drawn out, and immediately covered up
from the air with the siftings of coke, and allowed to cool gradually in the
heap.
of
I treat ingots of steel in the same manner, in order to render them more
homogeneous, and to destroy any crystallization or state of strain in the mass
among its molecules.
If bars, rods, plates, &c. of steel, after conversion,
(above all, if the iron from which they are made be itself clean.) and after this
subsequent process in retorts be submitted to what is called "washing" heat,
and then hammered or rolled, "shear" steel, or steel analogous to it, may be
made without any welding process, and will be found to be highly homogeneous
and solid. Ingots so treated will be less liable to crack under the hammer.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim,-
The annealing or cementing of previously converted steel or steel ingots in
air-tight retorts raised to a cementing heat, but without the presence of
carbonaceous matter, so that the carbon already contained in the same may be
evenly distributed through the steel.
In witness whereof, I, the said Sir Francis Charles Knowles, have
hereunto set my hand and seal, this Thirteenth day of December,
One thousand eight hundred and fifty-eight.
FRANCIS C. KNOWLES. (L.S.)