IM- PROVEMENTS IN FURNACES FOR CALCINING ORES AND OTHER MINERAL SUBSTANCES
Year: 1868

page_text: LETTERS PATENT to John Borlase Brown, of Walker, in the County
of Northumberland, Copper Refiner, for the Invention of "IM-
PROVEMENTS IN FURNACES FOR CALCINING ORES AND OTHER MINERAL
SUBSTANCES."
Sealed the 29th December 1868, and dated the 3rd July 1868.
PROVISIONAL SPECIFICATION left by the said John Borlase Brown at
the Office of the Commissioners of Patents, with his 'Petition, on the
3rd July 1868.
I, JOHN BORLASE BROWN, of Walker, in the County of Northumberland,
Copper Refiner, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN FURNACES FOR CALCINING ORES AND OTHER MINERAL SUB-
STANCES," to be as follows:-
My Invention consists in constructing furnaces so that a close furnace
and an open furnace are combined in one. The ordinary way of heating
a close furnace is by passing the flame between the two arches at the
top of the furnace and then once or oftener under the tiles which form
the bottom of the furnace.

page_text: My Invention consists in converting the space between the two arches
into an open furnace to which the ore or mineral is first supplied; the ore
afterwards descends into the space below the lower arch, which space
forms the close furnace.
I carry out my Invention by levelling the top of the lower arch so as
to form an upper bed to receive the ore or mineral; this lower arch is
strengthened if necessary, and the distance between the two arches must
be sufficient to allow the ore to be worked on the upper bed or the
top of the lower arch. The flame passes first over the ore on the
upper and open bed and then under the ordinary lower bed to the
chimney.
By means of my Invention I am able to get rid of any excess of
sulphur on the upper bed before adding common salt or other chloride
to the ore in the lower bed or close furnace. The gases from the two
beds are kept separate and distinct, those from the lower bed being
collected and condensed if necessary.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Borlase Brown in the Great Seal Patent
Office on the 1st January 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BORLASE BROWN, of Walker, in the County of Northumberland, Copper
Refiner, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of July, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Borlase Brown, Her special licence
that I, the said John Borlase Brown, my executors, administrators, and
assigns, or such others as I, the said John Borlase Brown, 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
FURNACES FOR CALCINING ORES AND OTHER MINERAL SUBSTANCES," upon the

page_text: condition (amongst others) that I, the said John Borlase Brown, 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 John Borlase Brown, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, 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 furnaces so that a close furnace
and an open furnace are combined in one. The ordinary way of heating
a close furnace is by passing the flame between the two arches at the
top of the furnace and then once or oftener under the tiles which form
the bottom of the furnace.
My Invention consists in converting the space between the two arches
into an open furnace to which the ore or mineral is first supplied; the ore
afterwards descends into the space below the lower arch, which space
forms the close furnace.
I carry out my Invention by levelling the top of the lower arch so as
to form an upper bed to receive the ore or mineral; this lower arch is
strengthened if necessary, and the distance between the two arches must
be sufficient to allow the ore to be worked on the upper bed or top of the
lower arch. The flame passes first over the ore on the upper
and open
bed and then under the ordinary lower bed to the chimney.
By means of my Invention I am able to get rid of any excess of
sulphur on the upper bed before adding common salt or other chloride to
the ore in the lower bed or close furnace. The gases from the two beds
are kept separate and distinct, those from the lower bed being collected
and condensed if necessary. Should it be desired that the ore on the
upper and open bed be subjected to a lower degree of heat than when in
the lower bed or close furnace, this can be effected by causing the flame
from the fuel to pass first under the tiles which form the floor of the
lower bed, and then ascending to pass over the ore on the floor of the
upper bed, and thence to the chimney, or by causing the flame from the
fuel to pass under the tiles of the lower bed, then between the arch of

page_text: the lower bed and a set of tiles made to form the floor of the upper bed,
and then finally over the ore on the upper bed to the chimney.
Figure 1 of the accompanying Drawings is a sectional view of a
combined close furnace and open furnace constructed according to my
Invention. A is the lower bed or close furnace; B is the lower arch;
and C the upper arch; D, D, are the spaces or flues under the tiles of
the lower bed A; E, E, are the working doors. I level the top of the
lower arch B to form an upper bed F. The flame passes first over the
ore on the upper bed F and then under the lower bed A through the
spaces D, D,.to the chimney; or if, as before explained, it is desired that
the ore on the upper bed F. should be subjected to a lower degree of heat
than that on the lower bed A, the flame is caused to pass first through
the spaces D, D, and then to ascend and pass over the ore on the upper
bed F to the chimney.
Figure 2 represents a modified arrangement of my furnace, in which
spaces or flues G, G, are formed between the lower arch B and the upper
bed or open furnace F. In this furnace the flame is caused to pass
through the spaces D, D, then through the spaces G, G, and finally over
the ore on the upper bed F to the chimney. Other modifications of my
furnace might be made, but those herein-before described are sufficient
to enable the nature and extent of my Invention to be clearly under-
stood.
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 improvements in furnaces for calcining ores and other mineral
substances, the combination, substantially as herein-before described, of
a close furnace and an open furnace both heated. by the same fire-place
or fire-places.
In. witness whereof, I, the said John Borlase Brown, have here-
unto set my hand and seal, this Twenty-ninth day of December,
One thousand eight hundred and sixty-eight.