IMPROVEMENTS IN EXTRACTING CERTAIN METALS PROM ORES AND OTHER COMPOUNDS OF THESE METALS, SOME PART OR PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OBTAINING ANOTHER PRODUCT OR OTHER PRODUCTS FROM SUCH ORES OR COMPOUNDS
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
NEWTON, of the Office for Patents, 66, Chancery Lane, in the County of
Middlesex, Civil Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fifth day of December, in the seventh year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Newton, Her especial licence, full power, sole privilege and authority,
that I, the said William Newton, my executors, administrators, and assigns,
and such others as I, the said William Newton, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time and
at all times during the term of years therein mentioned, should and lawfully.
might make, use, exercise, and vend, within England, Wales, and the Town of
Berwick-upon-Tweed, an Invention of "IMPROVEMENTS IN EXTRACTING CERTAIN
METALS PROM ORES AND OTHER COMPOUNDS OF THESE METALS, SOME PART OR PARTS
OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OBTAINING ANOTHER PRODUCT OR
OTHER PRODUCTS FROM SUCH ORES OR COMPOUNDS," being a communication from a
foreigner residing abroad; in which said Letters Patent is contained a proviso,
obliging me, the said William Newton, by an instrument in writing under
my hand and seal, particularly to describe and ascertain the nature of the said
Invention, and in what manner the same is to be performed, and to cause
the same to be inrolled in Her Majesty's High Court of Chancery within six
calendar months next and immediately after the date of the said in part recited
Letters Patent, as in and by the same, reference being thereunto had, will
more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Newton, do hereby declare that the nature of the said Invention, and
the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
This invention of improvements in extracting certain metals from ores and
other compounds of these metals, some part or parts of which improvements
are alse applicable to obtaining another product or other products from such
ores or compounds, has been communicated to me by my correspondent abroad,
in nearly the following words:-The ores and compounds to which the said
Invention is applicable are those which contain the sulphurets of copper and
iron or of lead or zinc. To extract metals from these ores and compounds by
the operations in ordinary use, they are first calcined in open reverberatory
furnaces, called "calciners," in which the ore or compound is exposed to flame
and heated air produced by combustion of fuel, whereby sulphur is expelled
and sulphurous acid gas passes into the atmosphere, and although attempts
have been already made to substitute other apparatus for open reverberatory
furnaces so as to provide for sulphur being obtained and for sulphurous acid
gas being condensed, yet these furnaces are still used almost exclusively for
calcining the said ores or compounds.
The next operation is to smelt the calcined ore or compound, and this is
usually effected in a furnace called a "smelting furnace," distinct from and
unconnected with the calciner.
The said Invention consists, firstly, in calcining the said ores and com-
pounds by means of apparatus, which provides for effecting such calcination,
without exposing the ore or compound to flame or heated air produced by
combustion of fuel; and which also provides for obtaining the gas produced
by such calcination unmixed with smoke; which also provides for introducing
the ore or compound, first, into that part of the apparatus employed which is
the least heated, and afterwards into other parts of the apparatus which are
more heated, and in which the required calcination is completed. I call such
apparatus as I use to effect this part of the said improvements "my improved
calcining apparatus."
Secondly, in adapting such an apparatus as I have called "my improved
calcining apparatus" to a smelting furnace, so that the waste heat of this
furnace is applied to calcine the said ores or compounds, and so that the cal-
cined ore or compound may be transferred in a heated state directly from the
calcining apparatus to the smelting furnace, when such smelting furnace is of

page_text: a construction to receive the same. I call the combined apparatus by which I
effect this part of the said improvements "my improved compound furnace."
Thirdly, in decomposing such sulphurous acid gas as is produced free from
smoke during the calcination of the said ores or compounds, by causing it to
percolate through coke or coal heated to redness, and mixing the gases thereby
produced in such a manner and at such a temperature as provide for their
acting upon each other so as to produce free sulphur.
Fourthly, in decomposing such sulphurous acid gas by heating it to redness
together with suitable gas containing carbon and hydrogen, or either of them,
and in mixing these gases in such a manner and at such a temperature as
provide for their acting upon each other so as to produce free sulphur.
I will now describe the manner in which I prefer to carry the said improve-
ments into effect, but it will be obvious to those who are conversant with
chemical and metallurgical operations, that the arrangements herein described
may be considerably modified without departing from the nature of the said
Invention.
In the Drawings annexed to this my Specification the Figures marked 1, 2,
3, and 4, exhibit my improved compound furnace as adapted to calcine and
smelt the said ores or compounds of copper, consisting of my improved calcining
apparatus and a smelting furnace, the calcining apparatus being shewn in these
Figures as placed over the smelting furnace and communicating with it, so as
to provide for the calcined ore or compound being transferred directly into the
smelting furnace. Fig. 1 is a vertical and longitudinal section, taken through
the dotted red line marked 3, 4, in Fig. 4; Fig. 2 is a vertical and transverse
section, taken through the dotted red line marked 7, 8, in Fig. 1; Fig. 3 is
a vertical and transverse section, taken through the dotted red line marked
5, 6, in Fig. 1; and Fig. 4 is a horizontal section, taken through the dotted
red line marked 1, 2, in Fig. 1. In these several Figures the same
letters of reference are used to indicate similar parts. A is a smelting
furnace, of the usual construction, from which the flame and heated air
pass off by the flue B; C1, C2, C3, C4, are chambers formed of brick arches
in which the ore or compound is calcined; D, D, are flues for conducting
the flame and heated air passing from the smelting furnace in contact with
the chambers C, C, C and C+; E, E, are channels through which the ore or
compound is transferred from one chamber to another; F, F, are covers for
closing these channels; G,* G,* are channels through which the ore or com-
pound is transferred from the chamber C to the smelting furnace; and G, G,
are covers for closing these channels; K, K, are openings provided with doors
for obtaining access to the chambers C¹, C³, C³ and C, for raking and trans-

page_text: ferring the orc or compound; I, I, are dampers, to provide for regulating the
passage of flame and heated air through the flues D, D; J, J, are openings
provided with doors for obtaining access to the dampers I, I; S is a flue, by
which the flame and heated air passes from the calcining apparatus to a chim-
ney II; R, R, are channels provided with hoppers, Q, Q, for introducing ore
or compound into the calcining apparatus; L, L, are apertures for admitting
atmospherical air into the chamber C*; M, M, is a channel through which the
air so admitted passes to C³; N, N, are channels for passing this air to C²; and
O, O, is a channel for passing this air to C'; P is a pipe through which the
gas produced by the calcination passes of. When the compound furnace is in
regular course of working, each of the chambers C2, C3, C³ and C* contains a
charge of ore or compound, and each charge has undergone a different degree
of calcination; and when a smelted charge has been run off from the smelting
furnace, the chamber C ought to contain a charge of ore or compound suitably
calcined to be ready for the smelting furnace. This charge is then transferred
from the chamber C' to the smelting furnace through the channels G*, G*, and
these channels being closed with their covers G, G, the smelting is proceeded
with in the usual manner. The contents of the chamber Cs are then to be
transferred into the chamber C, those of C3 and C3 and those of C¹ into C³, and
a new charge of ore or compound is to be introduced into the chamber C³.
Whilst the charge in the smelting furnace is becoming melted the ore or com-
pound in the calcining apparatus should be raked in the usual manner, but less
raking will be required than in the ordinary operation of calcining, as the
same effect is produced by transferring the ore or compound from chamber to
chamber as herein-before described. The air admitted through the apertures
L, L, flows over the ore or compound in the chamber C, and passes through
the channel M, M, into the chamber C³, and from thence through the channels
N, N, into the chamber C, and from thence through the channel O into the
chamber C¹, from which it passes through the pipe P. This arrangement pro-
vides for the air which effects the calcination of the ore or compound in the
chamber C*, being successively brought into contact with and calcining the ore
or compound in the chambers C³, C², and C³, also for a smaller quantity of air
than is usually employed being sufficient, by which means a smaller quantity of
ore or compound is carried off by the current of air passing through the cal-
cining apparatus than is now carried off by the current of air passing through
the calciners in ordinary use, and the sulphurous acid gas produced by the
calcination of the ore or compound is mixed with a smaller proportion of air,
and is therefore suitable to be used for the production of sulphuric acid or
sulphur. The said ore or compound of copper contained in the chambers

page_text: C¹, C², C³, and C' being acted upon by air unmixed with smoke becomes more
perfectly calcined than by the ordinary method of calcination, so that when such
calcined ore is smelted, a sulphurous compound of copper, containing forty per
cent. or more of copper, is obtained as a product, and when such calcined sul-
phurous compound is smelted "coarse copper" is usually obtained as a product
of a quality suitable to be refined so as to produce "fine" copper," and the
number of processes and the expences which are now requisite to obtain "coarse
copper" from the said ores of copper are thereby diminished. The compound
furnace which I have described may be used for calcining and smelting the said
ores or compounds of lead, but for these ores or compounds I prefer to use a
compound furnace in which the smelting is effected by heat transmitted
through a brick arch, instead of by flame in contact with the ore or compound.
Fig. 7 in the annexed Drawings exhibits a longitudinal section of such a fur-
nace; the same letters of reference are used in this Figure as have been used
in Fig. 1, to indicate those parts of the calcining apparatus of this compound
furnace which are similar to the calcining apparatus shewn in Figure 1. A is
the chamber of the smelting furnace constructed in the usual manner; T, T, is a
brick arch enclosing the chamber A, and through which heat is transmitted to
effect the smelting; V is the fire-place; W, W, is a brick arch enclosing a flue
X, through which the flame and heated air passes from the fire-place; and B is a
flue which conducts the flame and heated air to the flues D, D, in contact with
the calcining chambers C', C2, C3, and C'; G* is a channel through which the
calcined ore or compound is transferred from the chamber C to the smelting
furnace. During the process of smelting the said ores or compounds of lead,
atmospheric air is admitted into the smelting furnace, and this air, together
with sulphurous acid gas, produced by the operation of smelting, passes through
the channel G* (which remains open) into the chamber C, and from thence
through the other chambers of the calcining apparatus. The operations of cal-
cining and of transferring the said ores or compounds of lead are conducted in
this compound furnace in the same manner as I have herein-before described
for calcining and transferring the ores or compounds of copper in the compound
furnace, Figure 1; and atmospheric air passes through the calcining chambers,
and sulphurous acid gas passes through the pipe P, in the same manner as I
have herein-before described in referring to Fig. 1. In the usual operations of
smelting sulphurous ores or compounds of lead much waste of lead is occasioned
by this being carried off by the current of heated air passing through the
smelting furnace, and a large quantity of sulphurous acid gas (produced by the
operation of smelting passes into the atmosphere. By means of my improved
compound furnace, exhibited in Fig. 7 of the annexed Drawings, I diminish

page_text: this waste of lead, and I obtain the sulphurous acid gas produced by the
operation of smelting the said ores or compounds of lead, also the sul-
phurous acid gas produced by calcining such ores and compounds, suitable
to be used for the production of sulphuric acid, or sulphur. In using the
apparatus ordinarily employed for smelting the said ores of zinc, it is not
convenient to transfer calcined ore from the calcining apparatus direct to
the smelting apparatus, and I, therefore, place my "improved calcining appa-|
ratus" adjoining to a zinc smelting furnace, and conduct the flame and heated
air passing from the smelting furnace into the lowest flue of the calcining
apparatus, and I use the same calcining apparatus as is exhibited in the
Figures marked 1, 2, 3, and 4 in the annexed Drawings. In the usual opera-
tions of calcining sulphurous ores of zinc much waste of zinc is occasioned by
this being carried off by the heated air passing through the calciners, and a
large quantity of sulphurous acid gas passes into the atmosphere. By means
of my improved calcining apparatus I diminish this waste of zinc, and I obtain
sulphurous acid gas suitable to be used for the production of sulphuric acid
or sulphur. As the draft of the smelting furnaces used with "my improved
calcining apparatus" will be effected in consequence of the flame and heated air
being conducted through the flues of the calcining apparatus, I connect these
flues with a chimney of sufficient dimensions to prevent inconvenience on this
account. When I use "my improved calcining apparatus" to calcine the said
ores or compounds without connecting it with a smelting furnace, I construct a
suitable fire-place of the usual kind, either immediately under or contiguous to
its lower chamber, and I conduct the flame from this fire-place through the
flues of the apparatus to the chimney in the same manner as I conduct the
flame from the smelting furnace when I use such apparatus connected with
a smelting furnace. The brickwork of the said smelting furnaces and of my
improved calcining apparatus should be well bound together, in the same
manner as the brickwork of furnaces and apparatus used for similar purposes
is usually bound together. In the Drawings annexed to this my Specification,
the Figures marked 5 and 6 exhibit the apparatus which I prefer to use for
decomposing the said sulphurous acid gas by means of coke or coal and for col-
lecting sulphur produced by such decomposition.
Figure 5 is a vertical section taken through the red dotted line 3, 4, of
Figure 6; and Fig. 6 is a horizontal section taken through the red dotted
line 1, 2, of Figure 5. In these Figures the same letters of reference are
used to indicate similar parts. P is a pipe connected with a calcining appa-
ratus, in which the said sulphurous acid gas is produced; A, A, is a chamber
for retaining solid matters passing from the calcining apparatus with the gas;

page_text: this chamber may be constructed in the same manner as the chambers used
for a similar purpose in the ordinary mode of calcining ores. It has suitable
apertures for withdrawing the deposit; B', is a flue from the chamber A to the
ash-pit under the fire-place C¹; and B3 is a flue from the chamber A to the ash-
pit under the fire-place C2; these flues are furnished with dampers D' and D
to provide for equalizing the quantity of gas passing to the fire-places C¹ and C²;
E' and E are apertures in the flues B' and B, to provide for the admission of
atmospheric air to support the combustion of the coke or coal in the fire-places
C and C²; these apertures are provided with dampers for regulating the
quantity of air admitted: The fire-places C and C² have grate bars for sup-
porting the coke or coal, also openings C3 and C to their ash-pits, which
openings are fitted with doors for closing them. The coke or coal is introduced
into the fire-places at their upper parts by the apertures F1 and F2, which are
furnished with covers fitting into grooves containing sand to prevent the escape
of gas; G is a chimney for receiving gas from the fire-places C¹ and C³;
Hand H are flues through which the gas passes into the chimney G after it
has percolated through the lower part of the coke or coal in the fire-places
C and C; J and J2 are pipes from the flues B and B to the flues H¹ and
H³, to provide for gas passing into the chimney G without percolating through
the coke or coal, and these pipes are furnished with dampers K' and K², for
regulating the quantity of gas passing through them; L, L, are brick parti-
tions in the chimney G, having apertures through them, so arranged as to
cause the direction of the currents of gases passing through the chimney to be
repeatedly changed (as shewn by arrows in Fig. 5), and thereby to mix the
various gases which are capable of acting upon each other, so as to produce
free sulphur sufficiently to effect such action; M, M, are holes closed with
glass for inspecting the interior of the chimney G; N is a pipe for conducting
gas from the chimney G to a cooling apparatus O, the upper part of which
is formed by a vessel (containing water) capable of being taken off for re-
moving such matters as may become condensed therein; Q is a pipe for con-
ducting the cooled gas to a filtering apparatus R. I prefer to construct this
filtering apparatus of double brick walls r, r, and I fill up the space z, z, between
these walls with pounded coke, or some other substance which is a bad conductor
of heat; at the lower part of this filtering apparatus I fix bars S similar to those
of a fire-grate, and I nearly fill the apparatus with lumps of coke, or broken
bricks or stones T, T; U is a moveable iron pan placed below the bars S; and
V is an aperture to provide an access to the filtering apparatus, and furnished
with a door for closing the same when the apparatus is at work; Wis a flue"
for conveying gas from the filtering apparatus R to the chimney of a smelting

page_text: furnace, or to some other chimney; X is an opening into the flue W to pro-
vide for examining the quality of the gas passing through this flue, and
furnished with a door for closing the same, and Y is a damper for regulating
the draft of this flue. In conducting the operations of calcining the said ores
compounds, of decomposing sulphurous acid gas produced by such calcination,
and of obtaining sulphur from the products of such decomposition, it is essential
that atmospheric air should be admitted into the calcining apparatus, and
that the gas produced by the calcination should pass through the apparatus in
which the decomposition of sulphurous acid gas is effected, also through the
apparatus in which sulphur is collected. I prefer to create the draft which is
necessary to effect these objects by means of the chimney G, and of the com-
munication by the flue W with another chimney in which a draft exists; a draft
suitable for working with such an apparatus as I have described may be ob-
tained by constructing the chimney G about thirty feet high, and with an
internal area equal to sixteen square feet, and by connecting the flue W with
a chimney having a a draft sufficiently powerful to overcome the resistance
to the passage of gas which is occasioned by the materials T, T, placed in
the filtering apparatus R. I prefer so to regulate the power of the draft in
the flue W (by means of the damper Y), that the gas passing through the
pipe Qmay be in such a state of pressure as to have a slight tendency to
escape into the atmosphere; because I thereby prevent the access of air into
those parts of the apparatus in which it might act injuriously by combining
with sulphur. I judge of the pressure of the gas with sufficient accuracy by
means of an aperture in the pipe Q; and I adjust the damper Y so that a small
quantity of gas escapes through this aperture when it is opened. A more
powerful draft through the calcining apparatus, and through the decomposing
and filtering apparatus, may be obtained by means of an air pump, or a blowing
machine (constructed of such materials as will sufficiently resist the injurious
action of the gas required to pass through it), and when I use either of these,
I prefer to remove the pipe Q, and to connect the exhausting part of the air
pump or blowing machine with the outlet end of the cooling apparatus O, and
the discharging part with the filtering apparatus R. The operations of
decomposing sulphurous acid gas by means of coke or coal, and of obtaining
sulphur from the products of such decomposition, should be commenced by
lighting fires in the fire-places C1 and C2; the openings C3 and C' to the ash-
pits being open to supply air, and the dampers D¹ and D2 being closed; coke
or coal should be supplied to these fires through the apertures F¹ and F², and
the ash pits should remain open, and the dampers D' and D closed until the
partitions L, L, in the chimney G have become heated to a full red heat,

page_text: which is ascertained by inspection through the holes M, M. The ash-pits
being then closed, and the dampers D¹ and Ds opened, sulphurous acid gas
passes through the ignited coke or coal in the fire-places C' and C2; coke or
coal should be supplied so as nearly to fill the fire-places C' and C³, and as this
becomes gradually heated to redness before it undergoes combustion, gas is ex-
pelled from it, which passes with the sulphurous acid and other gas through the
flues II and H into the chimney G. The greater portion of the sulphurous
acid gas admitted into the fire-places is decomposed during its percolation
through the ignited coke or coal and sulphur vapor is thereby produced, and a
portion of this vapor uniting with carbon and with hydrogen produces sulphuret
of carbon and sulphuret of hydrogen. The gases thus produced, together
with any sulphurous acid gas which may may not have been decomposed, pass
through the flues I and II' into the chimney G; and as the sulphurets of
carbon and hydrogen are capable of decomposing sulphurous acid, when they
are sufficiently mixed therewith at a full red heat, and of producing free
sulphur by such decomposition, I provide for their being thus mixed by
repeatedly changing the direction of the currents of the gases passing through
that part of the apparatus, which is suitably heated. A greater quantity of
the sulphurets of carbon and hydrogen is usually produced than can be decom-
posed by the quantity of sulphurous acid gas which is not decomposed in
passing through the fire-places, and when this is the case I introduce an
additional quantity of sulphurous acid gas into the flues H' and H' by means
of the pipes J' and J. I judge of the quantity of this gas, which is required,
by examining the quality of the gas passing through the flue W, and if this
gas contains sulphuret of hydrogen I adjust the dampers K¹ and K2, so as to
adinit of a larger quantity of sulphurous acid gas passing into the flues II' and
II, and if it contains sulphurous acid I adjust these dampers so as to diminish the
quantity of gas passing directly into these flues. I find that paper moistened
with a solution of lead is a convenient test for indicating the presence of
sulphuret of hydrogen, and blue litmus paper or reddened turmeric paper for
indicating the presence of sulphurous acid. I regulate the combustion of the
coke or coal in the fire-places C¹ and C² by admitting more or less air through
the apertures E' and E, so that those parts of the apparatus by which the
currents of the gases are changed may be kept at a full red heat, and I
ascertain that such heating is effected by inspection through the holes M, M.
The gases, together with the sulphur produced (in the state of vapour) pass
from the chimney G, through the pipe N, to the cooling apparatus O, which
I prefer to construct of iron, the upper part of which apparatus consists of a

page_text: pan containing water; the dimensions of this pan and the quantity of water
supplied to it are so regulated that the cooled gases and vapor passing from
this apparatus may have a temperature of about three hundred and fifty
degrees of Fahrenheit. The cooled gases and vapour pass through the pipe Q
to the filtering apparatus R, which is so constructed that the gases (which
should enter it at a temperature between three hundred and fifty and three
hundred degrees of Fahrenheit) in passing through the same may not become
cooled below the temperature at which solid sulphur fuses, (about two hundred
and twenty-six degrees of Fahrenheit); I prefer to accomplish this by con-
structing the filtering apparatus R, as I have herein-before described, at the
said degrees of temperature sulphur vapour condenses, and as the gases pass
through the filtering apparatus R, the particles of sulphur mixed therewith
become arrested by the pieces of coke or other material contained therein, and
as sulphur is a fluid at the said degrees of temperature, it flows down the
filtering apparatus R, and is received in the pan U. I ascertain the tem-
perature of the gases in the upper and the lower part of the said filtering
apparatus by means of thermometers, having their bulbs either exposed to the
gases or placed in tubes containing oil, which tubes are exposed to the gases.
Instead of using the filtering apparatus herein-before described for collecting
sulphur (produced by the decomposition of the said sulphurous acid gas), this
sulphur may be collected by means of apparatus similar to those which are in
ordinary use for collecting the finely divided carbon called "lamp black." When
I use such an apparatus I prefer to have the cooling apparatus 0 of such
dimensions, and so to regulate the supply of water to this apparatus, that the
gases passing from the same may be cooled to a temperature of about two
hundred and twelve degrees of Fahrenheit, and I thereby obtain sulphur as a
finely divided powder in the collecting apparatus. I connect this apparatus
with a chimney by means of a flue, in the same manner as I have described for
connecting the filtering apparatus R with a chimney, and I make such pro--
visions for regulating the draft in this flue, and for ascertaining the quality of
the gases passing from the collecting apparatus, as I have mentioned in
describing the flue W connected with the filtering apparatus R. It will
occasionally happen that a portion of the solid matter which passes from the
calcining apparatus with the gas, will pass through the chamber A, A, and
become mixed with the sulphur obtained; when the proportion of this matter
mixed with the sulphur is such as to render it desirable to separate it, I distil
the sulphur, and I thereby obtain sulphur of greater purity, and the said solid
matter is left as a residuin in the distilling vessel.

page_text: In the Drawings annexed to this my Specification, the Figures marked
8 and 9 exhibit such an apparatus as I prefer to use for decomposing the said
sulphurous acid gas, by means of suitable gas containing carbon and hydrogen,
or either of them. Fig. 8 is a longitudinal section of the said apparatus; and
Fig. 9 is a transverse section of the same, this section being taken through
the red dotted line marked 9, 10, in Fig. 8. In these Figures the same letters
of reference are used to indicate similar parts. A, A, is a vessel or chamber
constructed of fire bricks; B is a fire-place, the flame from which
passes under
the lower part of the vessel or chamber A, through the flues C, C, and over the
upper part of the said vessel or chamber to a chimney D; E, E, is a stopper
for closing the front end of the vessel or chamber A; F is a pipe fitted to the
stopper E, for conveying gas into the vessel or chamber A; H and I are
branch pipes communicating with the pipe F, and furnished with dampers h
and i, to provide for regulating the passage of gas through the same. One of
these pipes is connected with a calcining apparatus producing sulphurous acid
gas unmixed with smoke, and the other with an apparatus supplying some of
the gases herein-before mentioned, which contain carbon and hydrogen, or
either of them; and one of these gases, also sulphurous acid gas, are thereby
conveyed into the vessel or chamber A. That part of this vessel or chamber
under which the fire is placed, is filled with pieces of fire bricks or other
suitable materials K, which should be heated to a full red heat by means of
the fire, and the gases being caused to percolate through the said materials
become thereby heated and partly mixed. L, L, are brick partitions in tho
vessel or chamber A, constructed so as to leave apertures between them and
the vessel or chamber, and these apertures are so arranged as to cause the
direction of the currents of gases passing through the vessel or chamber, and
through these apertures to be repeatedly changed (as shewn by arrows in
Fig. 8) and thereby to effect a sufficient mixing of the said gases, so as to com-
plete their action upon each other, and to produce free sulphur: the said vessel
or chamber A, and the brick partitions L, L, being kept at a full red heat
during such operation by means of the fire. The gases and sulphur vapour
produced by such action pass from the vessel or chamber A into a chimney G,
which is connected with apparatus for cooling the gases and vapour, also for
collecting sulphur and for occasioning draft; these apparatus being similar to
those I have herein-before described as being connected with the chimney G in
Figures 5 and 6 of the annexed Drawings, I ascertain the quality of the gases
passing from the apparatus used for collecting sulphur thus produced, in the
same manner as I have herein-before pointed out in describing Figures 5 and 6;

page_text: and when these gases contain sulphurous acid, I admit a greater proportion of
gas containing carbon or hydrogen into the vessel or chamber A, and when
these gases contain sulphuret of hydrogen or of carbon, I admit a smaller pro-
portion of such gas into the said vessel or chamber. I can also decompose the
said sulphurous acid gas by means of suitable gas containing carbon and hydro-
gen, or either of them, by conducting the sulphurous acid gas and other gas
through tubes or retorts made of fire clay, and having proper fires for applying
heat thereto; and in using tubes or retorts for this purpose, I prefer to fill
them with pieces of bricks or other suitable materials for the purpose of
assisting in heating these gases to a proper temperature, and in mixing them
with each other. The gases which are suitable for decomposing the said sul-
phurous acid gas by the means herein-before described, are the gases containing
carbon and hydrogen, which are produced by decomposing coal or coal tar by
heat; also those which are produced by the action of water on ignited coal or
coke, and sulphuretted hydrogen gas, however this gas may be procured. I
claim as the Invention communicated to me by a foreigner residing abroad,-
Firstly, the calcining of the ores or other compounds of metals herein-before
mentioned, by means of an apparatus which provides for effecting such calcina-
tion without exposing the ore or compound to flame or heated air produced by
the combustion of fuel; and which also provides for obtaining the gas produced
by such calcination unmixed with smoke; and which also provides for intro-
ducing the ore or compound first into that part of the apparatus employed
which is the least heated, and afterwards into other parts of the apparatus which
are more heated, and in which the required calcination is completed.
Secondly, the adapting of such a calcining apparatus as is lastly herein-before
mentioned, to a smelting furnace, so that the waste heat of this furnace is applied
to calcine the said ores or compounds, and so that the calcined ore or com-
pound may be transferred in a heated state directly from such calcining appa-
ratus to the smelting furnace, when such smelting furnace is of a construction
to receive the same.
.
Thirdly, the obtaining of sulphur either by causing such sulphurous acid gas
as is produced free from smoke, during the calcination of the said ores and
compounds, to percolate through coke or coal heated to redness, and causing
the gases thereby produced to be mixed in such a manner and at such a tem-
perature as provide for their acting upon each other so as to produce free
sulphur, or by causing such sulphurous acid gas, together with such gas
containing carbon and hydrogen, or either of them, as is herein mentioned,
to be heated to redness, and to be mixed in such a manner, and at such a

page_text: Inrolled the same Fifth day of June, in the year above written.