IMPROVEMENTS IN THE MANUFACTURE OR CONSTRUCTION OF STEAM BOILERS OR GENERATORS, AND IN THE APPLICATION OF MATERIALS TO SUCH MANUFACTURE
Year: 1855

page_text: in the County of Middlesex, and of Glasgow, North Britain, Gentleman,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OR CONSTRUCTION
OF STEAM BOILERS OR GENERATORS, AND IN THE APPLICATION OF MATERIALS TO
SUCH MANUFACTURE."-A communication from Jackson, Brothers, Petin
Gaudet and Company, of Rive de Gier, in the Empire of France,
Engineers.
Sealed the 13th July 1855, and dated the 5th February 1855.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
5th February 1855.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OR
CONSTRUCTION OF STEAM BOILERS OR GENERATORS, AND IN THE APPLICATION OF
MATERIALS TO SUCH MANUFACTURE," a communication from Jackson, Brothers,
Petin Gaudet and Company, of Rivè de Gier, in the Empire of France,
Engineers, to be as follows:--
This Invention-relates to the manufacture or construction of boiler plates,

page_text: bolts, and rivets of cast steel, such plates, bolts, and rivets being applied to
the manufacture of steam boilers or generators, dispensing thereby with
the metals ordinarily employed for that purpose, such metals being either
too weak to bear any very great pressure of steam with actual safety,
too expensive to be generally applied. According to this Invention,
it is proposed to substitute cast steel plates and steel bolts and rivets for
cast, wrought iron, or copper plates, bolts, and rivets in the manufacture of
steam generators, whereby a much greater strength is obtained, admitting
thereby of the application of much thinner plates than those at present
employed in the construction of steam boilers without decreasing the strength
of the boiler. These plates will require, however, to be much thicker and
larger than ordinary steel plates, and as this metal is of a closer and finer
grain than the closest grained wrought iron, it will be requisite that the
machines employed in the manufacture of such plates, bolts, and rivets be
much stronger, more powerful, and larger than the machines at present in
use, more especially as the steel will not bear any very great temperature
without the risk of being deteriorated or burnt.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 4th August 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and
of Glasgow, North Britain, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of February, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I, the
said John Henry Johnson, my executors, administrators, or 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 "IMPROVE-
MENTS IN THE MANUFACTURE OR CONSTRUCTION OF STEAM BOILERS OR GENERATORS,

page_text: AND IN THE APPLICATION OF MATERIALS TO SUCH MANUFACTURE," at communication*
from Jackson, Brothers,. Petin Gaudet and Company, of Rive de Gier, in the
Empire of France, Engineers, upon the condition. (amongst others) that I, the
said John Henry Johnson, by an instrument in writing under my hand and
seal; should particularly 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 Henry Johnson, 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:-
"The said Invention relates to a novel application of cast steel, and consists
in the employment of cast steel. for the manufacture or construction: of steam
boilers or generators; the plates; bolts, screws, and rivets of such boilers,
according to this Invention, being all composed of cast steel, in place of cast
or wrought iron or copper, such metals being found generally either too weak
to bear great pressure or too expensive to be generally used for such purposes.
By the application, of cast steel plates, bolts, screws, and rivets to the
construction of steam boilers or generators, a considerable increase of strength
will be obtained, combined with great lightness, as the steel plates may be
made much thinner than the ordinary boiler plates of wrought iron without
decreasing the strength of the boiler. These cast steel plates will require,
however, to be made both thicker and larger than the steel plates hitherto
manufactured, and as this metal is of a much closer and finer grain than the
closest grain wrought iron, it will be found requisite to make the various
machines and tools employed in the manufacture of such steel plates, bolts,
and rivets much stronger and more powerful than those commonly used in
the manufacture of metal plates, especially as the steel will require to be
worked at a lower temperature than iron is usually worked at, in order to
prevent the possibility of its being burnt, and consequently seriously deterio-
rated. These plates of cast steel are made by casting plates sufficiently thick
after forging and rolling to form large sheets, which in extent will be equal to,
if not larger than, those composed of copper or wrought iron for the fire boxes
of locomotive engines or for ordinary boilers. For the working of these
sheets of cast steel, the whole of the mechanism employed therein will require,
as I have herein-before stated, to be much more powerful and extensive than
any hitherto employed in the working of iron or copper, and the rolls of the
rolling mills will require to be of much larger proportions than those hitherto

page_text: used for working or rolling steel. In the application of cast steel plates to the
purposes aforesaid, it is also proposed to use screws, bolts, and rivets of cast
steel, in order that they may be made correspondingly small and light in
proportion to the reduced thickness of the plates.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of the said Invention; but
what I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,-
The application and use of cast steel in the form of large plates, and in the
form of bolts, screws, and rivets to, and in the manufacture or construction of,
steam boilers or generators, in the manner herein-before described.
In witness whereof, the said John Henry Johnson hath hereunto set his
hand and seal, the Fourth day of August, One thousand eight hundred
and fifty-five.
J. HENRY JOHNSON. (L.S.)