AN IMPROVEMENT IN FURNACES FOR ROASTING METALLIC ORES
Year: 1875

page_text: LETTERS PATENT to Henry Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer,"
for the Invention of "AN IMPROVEMENT IN FURNACES FOR ROASTING
METALLIC ORES." A communication from abroad by Robert McCollum
Fryer, of the City and State of New York, United States of
America.
-
PROVISIONAL SPECIFICATION left by the said Henry Edward
Newton at the Office of the Commissioners of Patents, with his
Petition, on the 16th December 1875.
I, HENRY EDWARD NEWTON, of the Office for Patents, 66, Chancery
5 Lane, in the County of Middlesex, Civil Engineer, do hereby declare
*the nature of the said Invention for "AN IMPROVEMENT IN FURNACES FOR
ROASTING METALLIC ORES," to be as follows:—
m1
1.
T
thi Tuzantion in mano conocially to facilitate and reduce

page_text: quartz, but it may also be applied to the separation of the precious
metals from other ores in which they may be contained with baser
metals.
The Invention consists of an upright furnace of cylindrical form open
at the top and bottom and suspended in a framework by lugs. The
furnace is constructed with an interior wall or shell to form a water and
steam space, the object of which is, firstly, to prevent the inner shell
from rapidly burning out or oxidizing; and, secondly, to provide steam
with which to supply a steam jet blower located in the chimney stack
above the furnace.
-
The bottom of the furnace which is invertible and removable is
made in the form of an open vessel of larger diameter than the body of
the furnace, and is constructed with a double shell for a water space.
The furnace bottom is suspended from a frame in any suitable manner.
The upper part of the body of the furnace is closed by a double shell
chamber which contains a cone around which the gaseous products of
I combustion in the furnace may escape to a stack above. On to the
exterior of the cone water is allowed to flow, which as it falls over the
edges of the cone meets the gaseous and volatile products escaping from
the furnace and condenses certain metallic and other portions of these
products which fall with the water and are collected therewith in a
suitable receptacle. The ore is roasted in the furnace by the combustion
of wood upon which it is deposited. Air is freely supplied to the said
furnace through an annular opening provided around its removable or
invertible bottom for the combustion of the fuel, and the oxidation of
the oxidizable portions of the ore and this supply of air is or may be
increased by a jet of steam from the steam jet blower in the chimney
stack.
Water is admitted to the water spaces by suitable pipes and overflow
pipes, and steam valves are supplied where they are required.
The suspended removable bottom serves to permit the rapid discharge.
of the contents of the furnace after the roasting has been completed.
By the roasting process in this furnace the precious metals are to such
11

page_text: ore having been brought to such condition by the roasting process that
its complete reduction to an exceedingly fine powder is very greatly
facilitated.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Edward Newton in the Great Seal Patent
Office on the 16th June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY.
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of December, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Henry Edward Newton, Her
special licence, that I, the said Henry Edward Newton, my executors,
administrators, and assigns, or such others as I, the said Henry
Edward Newton, 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 "AN IMPROVEMENT IN FURNACES FOR ROASTING METALLIC ORES,"
being a communication to me from abroad by Robert McCollum Fryer,
of the City and State of New York, United States of America," upon
the condition (amongst others) that I, the said Henry Edward Newton,
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 Henry Edward Newton, 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, reference being had to the Drawing here-

page_text: 4
say) :-
The object of this Invention is more especially to facilitate the
operation and reduce the cost of extracting the gold and silver which is
contained in quartz, but it may also be applied to the separation of the
precious metals from other ores in which they may be contained with
baser metals.
The Invention consists in an upright furnace of cylindrical form
which has a double wall or shell of boiler plate or other iron for con-
taining water and steam, and a suspended invertible or removable
bottom, and has in its upper part a cone around which the gaseous
products of combustion in the furnace may escape to a stack above, and
on to the exterior of which is delivered water which falls over the edges
and meets the gaseous and volatile products escaping from the furnace,
and condenses certain metallic and other portions of said products which
fall with the said water, and are collected therewith in a suitable
receptacle while the ore is being roasted in the furnace by the com-
bustion of wood, upon which the said ore is deposited therein. Air is
freely supplied to the said furnace through an annular opening provided
around its removable or invertible bottom for the combustion of the fuel
and the oxidation of the oxidizable portions of the ore, and this supply
of air is or may be increased by steam which is generated by the heat of
the interior of the furnace from the water in its double wall or shell,
and introduced in jets to the stack to act as a blower, such water serving
also to prevent the rapid burning or oxidation of the inner wall or shell
of the furnace.
The suspended removable or invertible bottom serves to permit the
rapid discharge of the contents of the furnace after the roasting has
been completed. By the roasting process in this furnace the precious
metals are to such extent separated from the mineral matters and the
base metals which are oxidized by the roasting process, that their
complete separation may be easily effected by pulverization and sub-
sequent amalgamation, the ore having been brought to such a condition
by the roasting process that its complete reduction to an exceedingly
fine powder is very greatly facilitated.
The Invention is illustrated in the accompanying Drawing, which
represents a central vertical section of the furnace.

page_text: The body A of the furnace constituting the furnace proper is of
upright cylindrical form, open at the top and bottom, and suspended on
or in a framework B by lugs C. This furnace is constructed of boiler
plate or other iron with a double shell D, E. Between the shells D, E,
a water and steam space is provided, the object of which is in the first
place to prevent the inner shell E from rapidly burning out, and in the
second place to provide steam with which to supply a steam jet blower F.
located in the stack or chimney S above the furnace. H is the bottom
of the furnace made in the form of an open vessel of an internal
diameter larger than the external diameter of the body of the furnace,
and constructed with a double shell having a water space to prevent
rapid oxidation of its interior. The said bottom is suspended from the
frame B by rods I connecting therewith by trunnions J, and with
apparatus overhead by means of which the said bottom may be raised
and lowered at pleasure. K is a double shell chamber situated at the
top of the body of the furnace, and through the inner shell of which the
gaseous products of combustion and volatile matters from the furnace
pass to the stack S which is erected above said chamber. The space
between the two shells of this chamber K contains water which prevents
the burning out of the inner shell. L is a cone which is located, as
shown, over the upper and conical portion of the inner shell of the
chamber K, and upon this cone L is delivered a stream of water through
a pipe M, which water comes in contact with the gaseous and volatile
products of the furnace as they pass in the direction indicated by the
arrows, and afterwards falls into the space between the inner and outer
shells of the chamber K. N is an overflow pipe for conducting the
water from the space between the shells of the chamber K after it has
performed the operation of condensing the volatile, metallic, and some
other products of combustion which have been evolved from the furnace,
and which are collected in the said space. The deposits collected in the
chamber K may be removed from time to time through a covered
opening provided for the purpose near the bottom of the chamber. O is
a pipe for conducting steam from the space surrounding the body of the
furnace to the steam blast or blower F; P is a pipe for feeding water to
the above-mentioned space.

page_text: manner in lumps of any size that will enter the furnace on to the top of
the wood which is then ignited at the bottom. The result is that the
principal portion of the wood is converted into charcoal before a great
amount of the same is consumed, after which the whole charge is
gradually raised to a very high temperature in the presence of a large
flow of air entering the furnace between the body A and the bottom H,
as indicated by arrows, the influx of said air being urged by the action
of the steam blast as soon as sufficient steam is generated. The effect
is that the sulphur and other volatile matters are mostly expelled, while
the baser metals are converted into oxides in the furnace, leaving the
precious metals in comparatively a free state for amalgamation.
The relative quantities of ore and fuel supplied to the furnace may be
about one and a quarter tons of wood to four tons of ore, or in like pro-
portion according to the capacity of the furnace, but these proportions
may be varied according to the nature of the ore under treatment.
After the charge of fuel has completely burned out the bottom H is
lowered and turned upon its trunnions sufficiently to precipitate the
contents of the furnace into a pit R below or into or on any other
suitable place or receptacle, from whence it may be gathered for further
treatment. The bottom is then replaced in the position shown in the
Drawing, when it is ready to receive another charge for a repetition of
the operation.
"
Having now set forth the nature of the Invention of "An Improve-
ment in Furnaces for Roasting Metallic Ores as communicated to me
by my foreign correspondent, and explained the manner of carrying the
same into effect, I wish it to be understood that under the above in part
recited Letters Patent I claim, the furnace A, cone L, and bottom H,
combined substantially as and for the purpose above set forth.
In witness whereof, I, the said Henry Edward Newton, have
hereunto set my hand and seal, the Fifteenth day of June, in
the year of our Lord One thousand eight hundred and seventy-