IMPROVEMENTS IN CHAMBERS FOR CONDENSING THE FUMES. PROVISIONAL SPECIFICATION
Year: 1881

page_text: LETTERS PATENT to Horatio Nelson Lay, of Rumleigh, near Tavistock, in the
County of Devon, Companion of the Most Honourable Order of the Bath, and
Harry Bulford, of Calstock, in the County of Cornwall, Mining Captain, for an
Invention of "IMPROVEMENTS IN CHAMBERS FOR CONDENSING THE FUMES.
PROVISIONAL SPECIFICATION left by the said Horatio Nelson Lay and
Harry Bulford at the Office of the Commissioners of Patents on the 6th May
1881.
HORATIO NELSON LAY, of Rumleigh, near Tavistock, in the County of Devon,
Companion of the Most Honourable Order of the Bath, and HARRY BULFORD, of
Calstock, in the County of Cornwall, Mining Captain. IMPROVEMENTS IN
CHAMBERS FOR CONDENSING THE FUMES OBTAINED BY ROASTING ARSENICAL
PYRITES AND SULPHUROUS PYRITES."
Chambers for condensing the fumes obtained by roasting arsenical pyrites and
sulphurous pyrites are ordinarily constructed of brick, the roof, which is of con-
siderable thickness, being formed either entirely of brick or of brick covered with
stone, and the interior of the said chambers being divided by transverse walls into
compartments, which communicate with each other by means of openings in the
said transverse walls, the openings being so arranged relatively to each other
as to cause the fumes in passing through the said chambers to take a zig-zag
course.
Chambers thus constructed are not durable, the combined action of the sulphur
contained in the fumes passing through them, and of rain which enters the roof at
the interstices caused by contraction and expansion rapidly destroying the materials
of which they are built. The said chambers also act very imperfectly, owing to
the retention of heat by the said materials, much of the arsenic contained in the
fumes, instead of being condensed and deposited in the chamber, is carried out
[7) 017

page_text: therefrom and lost; or if retained is frequently so burned as to be useless, and part
of the sulphur contained in the said fumes is also carried out, and is converted into
sulphurous acid, which causes the destruction of vegetation in the neighbourhood
of the said chambers.
The object of our Invention is to remedy these defects. In carrying out our said
Invention we form or build flues in the transverse walls of the chamber, through
which flues currents of air from the exterior of the chamber pass, and we cover the
said chambers with a roof of iron. By these means the heat absorbed from the
fumes is rapidly removed, and thrown off from the chamber. In order to protect
the iron roof from the action of rain we erect over it a light covering or outer roof
of wood, iron, or other suitable material, leaving sufficient space between the two
roofs to admit of the free passage of air between them, and the free radiation of heat
from the inner or main roof of the chamber.
In order to prevent the rapid destruction of the brickwork of the chamber by
the expansion and contraction caused by the heating and cooling thereof, we brace
the outer walls together by means of bars or rods of iron, which we pass through
the air flues in the transverse walls, in order that the said bars or rods may be
kept cool and out of contact with the fumes in the chamber. By thus bracing the
walls we are enabled to build them of less than the ordinary thickness, and the
radiation of the heat absorbed by them from the fumes is consequently much
facilitated.
Instead of forming the walls and the interior of the roof of the chamber entirely
of brickwork, we in some cases form a portion of the said chamber near the end at
which the fumes enter parily or entirely of iron. By this construction of the
chamber the burning of the arsenic or part thereof contained in the funies is
prevented, the heat of the fumes being very rapidly lowered on entering the:
chamber.
Chambers constructed according to our Invention are cheaper in first cost than
those of the ordinary construction, beside being considerably more efficient and
durable
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Horatio Nelson Lay and Harry Bulford in the Great Seal Patent
Office on the 5th November 1881.
HORATIO NELSON LAY, of Rumleigh, near Tavistock, in the County of Devon,
Companion of the Most Honourable Order of the Bath, and HARRY BULFORD, of
Calstock, in the County of Cornwall, Mining Captain.. IMPROVEMENTS IN
CHAMBERS FOR CONDENSING THE FUMES OBTAINED BY ROASTING ARSENICAL-
PYRITES AND SULPHUROUS PYRITES."
Chambers for condensing the fumes obtained by roasting arsenical pyrites and
sulphurous pyrites are ordinarily constructed of brick, the roofs, which are of con-
siderable thickness, being formed either entirely of brick or of brick covered with
stone, and the interior of the said chambers being divided by transverse walls into
compartments, which communicate with each other by means of openings in

page_text: the said transverse walls, the openings being so arranged relatively to each other
as to cause the fumes in passing through the said chambers to take a zig-zag
course.
Chambers thus constructed are not durable, the combined action of the sulphur
contained in the fumes passing through them, and of rain which enters the roof at
the interstices caused by contraction and expansion, rapidly destroying the materials
of which they are built. The said chambers also act very imperfectly. Owing to
the retention of heat by the said materials, much of the arsenic contained in the
fumes, instead of being condensed and deposited in the chamber, is carried out
therefrom and lost; or if retained is frequently so burned as to be useless, and part
of the sulphur contained in the said fumes is also carried out, and is converted into
sulphurous acid, which causes the destruction of vegetation in the neighbourhood
of the said chambers.
The object of our Invention is to remedy these defects. In carrying out our said
Invention we form or build flues in the transverse walls of the chamber, through
which flues currents of air from the exterior of the chamber pass, and we cover the
chamber with a roof of iron.
By these means the heat absorbed from the fumes is rapidly removed and
thrown off from the chamber. In order to protect the iron roof from the action of
rain we erect over it a light covering or outer roof of wood, iron, or other suitable
material, leaving sufficient space between the two roofs to admit of the free passage
of air between them, and the free radiation of heat from the inner or main roof of
the chamber.
In order to prevent the rapid destruction of the brickwork of the chamber by
the expansion and contraction caused by the heating and cooling thereof, we brace
the outer walls together by means of bars or rods of iron, which we pass through
the air flies in the transverse walls, in order that the said bars or rods may be
kept cool and out of contact with the fumes in the chamber. By thus bracing the
walls we are enabled to build them of less than the ordinary thickness, and the
radiation of the heat absorbed by them from the fumes is consequently much
facilitated.
Having thus described the nature of our Invention we will proceed to describe
the manner in which it is to be performed, reference being had to the accompanying
Drawing, and to the letters and figures marked thereon.
Figure of the said Drawing is a side elevation, and Figure 2 is an end elevation
of a chamber constructed according to our Invention; Figure 3 is a plan partly in
section taken on the line A, A, Figure 1: Figure 4 is a vertical longitudinal section
taken on the line B. B. Figure 3; and Figures 5 and 6 are transverse sections
taken respectively on the lines C, C, and D. D, Figure 1. The same letters and
figures of reference indicate the same parts in each of the Figures of the
Drawings.
a. a. are the outer walls of the chamber: b, b. are the transverse walls of the
said chamber, by which it is divided into compartments c. c. each of which is
provided with a door of iron d. d. as usual to admit of access to the interior of the
chamber e is the flue by which the fumes pass into the chamber, and is the flue
by which the fumes pass from the chamber to a chimney shaft, the said fumes
passing from one compartment to another through apertures in the transverse walls
as usual. The direction in which the fumes pass is indicated by the barbed arrows
in Figure 3. Those of the said apertures which lie on the lines of section are
shown in Figures 3 and 4 of the Drawing, and are marked b', '. One of the said
apertures is also shown in Figures 5 and 6. ². 6². 1, 63, 64, 6, are the flues formed
in the transverse walls b. b, the horizontal fines 2. ', in each of the walls being
each open at one end to the external atmosphere. and connected at their other ends
by the vertical flue b. as best seen in Figure 6. Through these flues air passes, as
indicated by the headless arrows in Figures 3, 4, and 6.
In order to provide for the rapid cooling of the fumes in passing from one com-
partment to another through the apertures b', b', we form or arrange the air

page_text: flues b, b, b; in the several transverse walls, so that each of the said apertures is
nearly surrounded by the said air flues, as shown in Figure 6, the openings of the
said flues in each alternate wall are thus on one side of the chamber, and those of
the other walls on the opposite side; g g, are the rods passing through the air
flues b, b, by which rods the outer walls of the chamber are braced together, the
ends of the said rods projecting from the open ends of the said flues, being passed
through and secured by nuts or otherwise to plates or bars g': g'. placed across the
said open ends, and bearing on the brickwork on either side of them; h is the iron
roof of the chamber, the inner side of which may if necessary be protected from the
action of the sulphur contained in the fumes by a thin coating of plaster of Paris;
i is the outer roof or covering, which may be of wood or other convenient and
suitable material. The said outer roof (which is not shown in Figure 4) is
supported on piers a', a', built on the walls a, a, and of sufficient height to admit
of a free passage of air between the two roofs. The flues e, f, leading into and from
the chambers are roofed or covered with iron e' f', which may be protected by an
outer roof of any suitable material, as herein before described with reference to the
chambers, and illustrated in Figures 1, 2, 3, 5, and 6 of the Drawings, and in the
walls of the said flues air flues may be formed, in order to assist in cooling the
fumes, the said air flues being arranged so that currents of air may pass freely
through them.
In order to increase the draught of air through the flues in the transverse walls
of the chamber, and those in the walls of the flues e, f. their exit ends may be
connected by means of other flues or by means of pipes with a chimney shaft.
Chambers constructed according to our Invention are cheaper in first cost than
those of the ordinary construction, beside being considerably more efficient and
durable.
Having now described the nature of our Invention, and the manner in which
the same is to be performed, we wish it to be understood that we do not limit
ourselves to the precise details described, as they may be varied without departing
from the nature of our said Invention, but we claim as our Invention of "Improve-
ments in Chambers for Condensing the Fumes Obtained by Roasting Arsenical
Pyrites and Sulphurous Pyrites,"
First. Forming flues in the walls of the said chambers, the said fines being so
arranged that currents of air may pass through them for the purpose of removing
the heat absorbed by the said walls from the fumes passing through the
chambers.
Secondly. Forming the roofs of the said chambers of iron.
Thirdly. Bracing together the outer walls of the said chambers by means of bars
or rods passed through the air flues in the transverse walls.
In witness whereof, J, the said Horatio Nelson Lay, have hereunto set my
hand and seal this Fourth day of November, in the year of our. Lord
One thousand eight hundred and eighty one.