IMPROVEMENTS IN CUPOLA AND OTHER BLAST FURNACES
Year: 1865

page_text: LETTERS PATENT to Richard Canham, of Clerkenwell, in the County
of Middlesex, Foundry Manager, for the Invention of "IMPROVEMENTS IN
CUPOLA AND OTHER BLAST FURNACES."
Sealed the 21st November 1865, and dated the 26th May 1865.
PROVISIONAL SPECIFICATION left by the said Richard Canham at the
Office of the Commissioners of Patents, with his Petition, on the 26th
May 1865.
I, RICHARD CANHAM, of Clerkenwell, in the County of Middlesex, Foundry
Manager, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN CUPOLA AND OTHER BLAST FURNACES," to be as follows:-
My Invention consists in constructing cupola and other blast furnaces in
manner hereafter described. I support the furnace upon pillars, and leave
an open space below the point at which melting takes place. I insert in this
space bars of fire-brick or other like suitable material, and I surround the
furnace with a jacket open at bottom for the admission of air. The jacket is
tapered off at top, contracted, and terminates in tubular apertures, or in a
narrowed annular mouth inside the shaft or chimney over the top of the
furnace. Air from the space first mentioned is free to enter into the furnace
as well as into the jacket, or air may be admitted to the jacket through

page_text: hollow columns. I dispense with tuyeres, and on the furnace being charged
and lighted the air becomes heated and rarefied in the jacket, and issuing
from the narrowed mouth causes air to be drawn into and up through the
contents of the furnace. In some cases I dispense with the jacket and create
a draught into and through the furnace by a tall shaft. Again, I sometimes
make two or more furnaces constructed as before described with air apertures
at bottom communicate with one shaft common to all. To regulate the admis-
sion of air into the jacket and furnace, or either, I employ a cylindrical screen
outside the space first described, and apply counterweights to enable the
screen to be readily raised and lowered.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Canham in the Great Seal Patent Office on the
25th November 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
CANHAM, of Clerkenwell, in the County of Middlesex, Foundry Manager, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of May, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Richard Canham, Her special licence that I, the said Richard Canham,
my executors, administrators, and assigns, or such others as I, the said Richard
Canliam, my 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 Invention for "IMPROVEMENTS IN CUPOLA AND
OTHER BLAST FURNACES," upon the condition (amongst others) that I, the said
Richard Canham, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, 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 Richard Canham, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the Drawings hereunto annexed,
that is to say:-
My Invention consists in constructing cupola and other blast furnaces in
manner herein-after described. I support the furnace upon pillars, and leave
an open space below the point at which melting takes place. I insert in this
space bars of fire-brick or other like suitable material, and I surround the
furnace with a jacket open at bottom for the admission of air. The jacket is
tapered off at top, contracted, and terminates in tubular apertures, or in a
narrowed annular mouth inside the shaft or chimney over the top of the
furnace. Air from the space first-mentioned is free to enter into the
furnace as well as into the jacket, or air may be admitted to the jacket
through hollow columns. I dispense with tuyeres, and on the furnace being
charged and lighted the air becomes heated and rarefied in the jacket, and
issuing from the narrowed mouth causes air to be drawn into and up through
the contents of the furnaces. To regulate the admission of air into the jacket
and furnace, or either, I employ a cylindrical screen outside the space first
described, and apply counterweights to enable the screen to be readily raised
and lowered.
Figure 1 of the accompanying Drawings is a vertical section of a furnaced
constructed according to my Invention; A, A, is the furnace, and B, B, are
pillars on which it is supported; C is the basin or receptacle into which the
molten metal falls, and from which it is run by the tap hole D; E is an open
space between the furnace A and the basin C; bars of fire-brick or other like
suitable material are inserted in this space; the manner in which I prefer to
place these bars in the space is to form a channel round the basin C as repre-
sented at O, Figure 3, into which I drop the bricks P endwise; G, G, is a jacket
surrounding the furnace, and open at bottom for the admission of air; this
jacket is tapered off and contracted at top as shewn, and terminates in tubular
apertures H as seen more clearly in Figure 2, which is a plan of the top of
the jacket. Instead of a single series of apertures the jacket may terminate
in a double series as represented in sectional elevation in Figure 3, or it may
terminate in a narrowed annular mouth or mouths as represented in plan in
Figure 4. In some cases I form additional apertures from the jacket into
the furnace as represented at F. The mouth or upper end of the jacket is
inside the shaft or chimney I of the furnace. Air is free to enter the furnace
between the bars in the space E as well as into the jacket G. K is a cylindrical
screen outside the space E for regulating the admission of air into the jacket
G and for protecting the workmen from the fire. This screen is connected to

page_text: counterweights L, L, to enable it to be readily raised and lowered as required.
It is prevented being lowered below the bottom of the jacket G by a ring M
on the screen coming against a corresponding ring N on the jacket. On the
furnace being charged and lighted the air becomes heated and rarefied in the
jacket G, and issuing from the narrowed mouth causes air to be drawn into and
up through the contents of the furnace. Sometimes I make the pillars B, B,
hollow, and admit air to the jacket G through them. In some cases I
dispense with the jacket G and create a draught into and through the furnace
by a tall shaft. Again, I sometimes make two or more furnaces constructed
as before described with air apertures at bottom communicate with one shaft
common to both or all.
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 as my "improve-
ments in cupola and other blast furnaces,-
First, the arrangement and combination of parts of furnaces substantially
as herein-before described and represented in the accompanying Drawings.
Second, surrounding furnaces with a jacket arranged substantially as herein-
before described and represented in the accompanying Drawings.
Third, the employment of a screen substantially as and for the purposes
herein-before described and represented in the accompanying Drawings.
In witness whereof, I, the said Richard Canham, have hereunto set my
hand and seal, this Twenty-fifth day of November, One thousand eight
hundred and sixty-five.
RICHARD CANHAM.
(L.S.)