IMPROVEMENTS IN APPARATUS FOR TREATING METALS AND METALLIC ORES
Year: 1865

page_text: Wales, Mining Engineer, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR TREATING METALS AND METALLIC ORES," bearing date
the Thirteenth March, One thousand eight hundred and sixty-five,
No. 697.
DISCLAIMER AND MEMORANDUM OF ALTERATION proposed by
WILLIAM PROSSER, of 19, Limerston Street, Chelsea, in the County.of
Middlesex, to whom the said Letters Patent have been assigned, and
who is duly registered as the proprietor thereof, to be filed in the Great
Seal Patent Office with the Specification to which the same relates,
according to the Statute in that case made and provided.
WHEREAS since the date of the said Letters Patent and that of the filing
of the Specification thereof by the Patentee, and also since the said Letters
Patent were assigned to me, the said William Prosser, I have been advised
that certain apparatus described in the said Specification, and delineated on
the accompanying Sheet of Drawings, cannot be competently claimed under
the said Letters Patent, therefore I desire to disclaim certain parts of the said
Specification and Drawings, and to alter the same consistently with such
disclaiming, and I also desire to alter and amend certain obvious clerical
errors contained in the said Specification.

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"
NOW KNOW YE, that I, the said William Prosser, by and with the leave
of Her Majesty's Attorney-General, do hereby disclaim the following words:-
For lead or copper ores where the extraneous matter is easily detached
"from the metallic portions it will be found convenient to adopt a simple
"form of apparatus in lieu of the inclines either in conjunction with or
independently of the rotating sieves; it consists of a concave pan or dish
" with a raised wire or perforated screen on its edge, having a suitable gutter
" or channel outside it for the purpose of receiving any portion of the water
" and matter that may pass through the screen, and conducting it through a
"shoot or spout to a suitable receptacle. I poise the pan or dish upon a ball-
"and-socket joint so as to admit of its receiving a rocking motion in every
"direction, which I communicate to it by any convenient suitable movement.
"A graduated stream of water is allowed to flow into the pan and to escape
by a suitable overflow pipe by which the extraneous matter is separated
from the metallic portion of the ore and collected for subsequent examina-
"tion in a tank or reservoir contiguous to it;" contained in the said
Specification and occurring in the twenty-fifth and thirteen following lines of
page 5 thereof, as printed by Her Majesty's Printers; also the following words,
figures, and letter, "Figures 6, 7, 8, sections and plan of rocking pan or dish
driven by crank "T," contained in the second and third lines of page seven
of the said Specification, printed as aforesaid; as also the following words, "I
claim the application and use of a rocking pan or dish as herein described;"
Thirdly," contained in the twenty-first, twenty-second, and twenty-third lines of
page seven of the said Specification, printed as aforesaid; as also the following
words, "and rocking pan," contained in the twenty-fourth line of page seven
of the said Specification, printed as aforesaid. I further bereby disclaim or
cancel Figures 6, 7, and 8 of the Drawings appended to the said Specification,
being the Figures referred to in what is herein-before stated to be disclaimed.
I hereby alter or amend the said Specification by substituting for the
following words "courser ores, excentric, it, on, and is, which, which, such,
excentric," contained respectively in line seventeen, page three, line nine,
page four, lines six and eighteen, page five, and lines nine, ten, twelve,
thirteen, twenty-three, and thirty-two, page six, the following words re-
spectively, namely, "coarser, ore, eccentric, they, or, being, wheel, wheel,
which, eccentric;" and by introducing the word "to" before the first word of
the last line of page six, the said words which I hereby thus alter or amend
being contained in the said Specification, as printed by Her Majesty's Printers
and certified by clerks in the Great Seal Patent Office.
And in order that the effect of the present Disclaimer and Memorandum of

page_text: Alteration may be clearly shewn and understood I will proceed to recite
(omitting the preamble and testing clause) the said Specification as proposed
to be hereby amended.
€6
"My improvements relate to the washing and separating of metals and
"metallic ores from the extraneous matters and substances with which they
"are ordinarily combined, and consist of an arrangement of sieves or perforated
"compartments on the periphery of one or more concentric wheels or rims,
"revolving vertically on a horizontal axis in a reservoir of water, the several
"wheels or rims (when more than one are used) successively discharging
"their contents into those which are outside them until the whole of the
"combined mass of material previously crushed (whether alluvial deposits or
ores) has been separated and cleansed from the extraneous matters and
"substances with which the metallic portion is intermixed. In the case of
"crushed ores the coarser or imperfectly crushed portions which are too
large to pass through the sieves or perforations in the compartments are
"delivered by the rims into a receptacle or receptacles from which they are
"conveyed to the crushers by travelling bands or other suitable mechanical
means to be further crushed or pulverized and again passed through the
separators. The subsident matter which is deposited in the bottom of the
"reservoir is discharged therefrom by scoops attached to the periphery
"of the revolving rims, or wheels, or otherwise, and is transferred to
sloping tables on which the metallic portions are separated and retained
while the extraneous matters are allowed to pass off to reservoirs, in which
any stray portions of metal may subside, the useless matters running to
"waste with the current of water which accompanies them. By these
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means I propose to perform the operations of washing and separating
"metals and metallic ores more perfectly by recovering a greater portion of
"the metals as well as more economically by the diminution of manual labor
"in the processes described.
<<
"
"In constructing and working the apparatus I employ materials and driving
power suitable and convenient for 'the intended object. The wheels or rims
"which form the body or framework upon which the sieve wire is placed
may be of wood or metal, or parily of both, as convenience may suggest,.
"and of dimensions suited to the quantity of ore to be treated. It will.be
"found that when the external diameter of the machine travels with a
velocity of about three feet per second sufficient traverse through the water
"will be obtained and the process satisfactorily carried out..
"
--
"For general purposes I propose to construct the disc or wheel forming
the body of the machine of wood, and of about five feet in diameter;, upon

page_text: "one face of which I fix one or more concentric rims, and secure them to
"the disc by suitable studs or brackets. To the periphery of these rims I
"attach wire or other perforated strainers (by preference copper wire gauze
"of suitable mesh), and I divide the rims into compartments of about three
"feet each in length, the partitions being of a curved form (by preference),
"and formed of wire gauze or perforated plate so as to admit of the water in
which the machine rotates passing freely through the ore, and cleansing it
"from extraneous matter and also to allow the water to drain away before
"the solid matter is discharged successively from the compartments, sufficient
46 space is allowed between the concentric rims or compartments to admit of
"the insertion of inclined aprons upon which the cleansed ore is discharged,
"and by which it is conveyed into the receptacles provided for the purpose;
"or it may be delivered on to travelling bands by which it is conveyed to
washing tables for further treatment. If the particles of the ore have not
"been sufficiently reduced in size for such treatment the bands will convey
"them to the crushing machinery to be further pulverized. The machine is
fed with the material as it comes from the crushing machinery at the
innermost rim of the series upon which the coarsest sieves or strainers are
fitted, the other rims being fitted with sieves or strainers increasing in
"fineness as they recede from the centre, so that the ore in passing from one
"rim to another may be gradually separated from the extraneous matters
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with which it is combined until the whole has been cleansed. The refuse
together with the finest portions of the metal or ore are deposited in the
"tank or reservoir in which the machine rotates. The hopper and shoot
through which the central series of compartments are fed are placed at
the side of the rim which descends into the water, and when the compart-
ments by the rotation of the machine successively arrive at the top they
discharge their contents on to the inclined aprons respectively, or on to the
travelling band. On the side of the disc opposite to that on which the
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"
" rims and strainers are fitted, and extending somewhat beyond the periphery
"of the outer rim, scoops of suitable form, number, and size are arranged
"so as to gather up the matter or matters deposited in the reservoir, the
"bottom of which is suitably formed to lead the matter into them; having
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raised the deposit from the bottom of the reservoir to the highest point to
"which the machine will elevate it the scoops successively discharge it on
"to an inclined apron, from whence it is conveyed together with the water
which accompanies it to a receptacle conveniently placed at the end of the
reservoir, where it is kept in a state of agitation by means of a rotating
rake worked by a band from the ax's of the disc, in which state it is
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caused to flow either through a perforated or wire gauze strainer, or over
a weir on to an inclined table, which may consist of one or more inclines
as the ore to be separated may require. On the first or upper incline I
propose to use rakes placed at intervals on a bar to which a to-and-fro
"motion is given by a crank or eccentric on the axis of the rotating 'rake,'
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by which movement the material on the incline is separated and disturbed
so as to effect the more complete detachment of the extraneous matter
"from the metallic portions of the ore. It is apprehended that one set of
"rakes will be sufficient for the purpose in ordinary cases, but should it be
"found necessary similar rakes may be applied to another or all the inclines.
"The number and extent of the inclines will depend upon the kind of
"metallic ore to be treated and to the character of the extraneous matter
"with which it is combined.. In cases where the extraneous matter is of a
more adhesive character longer inclines or a greater number of them will
"be necessary, and these may have means of adjustment so as to vary the'
inclination if desired. The washed ore will be removed from the inclines'
"in the usual manner, the slime and other extraneous matters passing off
"with the water into a reservoir, where they may be allowed to subside for
subsequent examination. It will be desirable to apply two scoops for
"cach compartment of the outer rim, and so to set them that they will not
comence discharging their contents until they arrive over the apron, and also
"that they be entirely discharged before they pass the apron, otherwise undue
"loss will ensue, which with the precious metals would be objectionable.
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"The Drawings hereunto annexed will illustrate more fully the means by
"which my Invention is proposed to be carried out, the Figures having letters'
"of reference denoting similar parts.
:
"Figure 1 represents a front view of the machine; Figure 2, au end view
"of the same; Figure 3, a back view of the same; Figure 4, a plan'
"of the same; Figure 5, a vertical section of the same taken through the
"centre of the machine.
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"A is the reservoir containing water, which may be stagnant or kept gently
flowing through at pleasure; B, the disc or wheel upon which the rims C
are secured by studs D; E, the compartments or sieves into which the metal
ore is fed, being successively transferred from one to the other; F, scoops
or buckets, which transfer the deposit from the bottom of the reservoir A
"to the inclined apron G; H, the axis on which the disc or wheel B is
"mounted, working in carriages fixed on the edge of the reservoir; I, a
band wheel for communicating motion to the axis. Small machines only
require manual power to work them applied to a winch; K, a feeding

page_text: hopper in which the crushed or pulverized material is deposited for feeding
"the machine; L, the inclined aprons upon which the matter remaining in
"the several compartments after having passed through the water is delivered,
"and from which it falls into a receptacle with partitions so arranged as to
"divide the different products of the washing.
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"As the material in the original state in which it comes from the crushers
"is fed into the centre series of compartments so it may happen that some
portions of it may not be sufficiently pulverized, which portions may be
"carried back to the crushing machinery by means of an endless band
"worked off the axis of the machine. M, an inclined shoot for conveying
"the deposit raised by the scoops to a reservoir N, in which a rotatory rake O
"revolves for the purpose of preventing the subsidence of the material therein,
"the water and material escapes or overflows through a perforated strainer
"or over a weir or waste board into a shoot, which conveys them to the
"inclined table P, whereon the heavier is separated from the lighter matter
" and the cleansing from extraneous matter being promoted by rakes Q on a
"bar R, which receives a to-and-fro or reciprocating motion from a crank or
"eccentric on the axis of the rotatory rake O, or the machine axis II; these
"rakes may also have a slight cross motion to enable them to stir up the
"material more completely, only one series of rakes are shewn, as it is
apprehended that they will be sufficient for the purpose, but others may be
"used on the other tables if found necessary and desirable. S are reservoirs so
placed as to receive the washings from the tables and cause them to flow
"under and over partitions placed therein so as to allow the metallic portion of
"the matter flowing through with the water to subside therein; suitable mud
"doors at the bottom should be added for getting ready access to the deposits.
"Having now described the nature of and the manner of applying and
using the improved apparatus, which I employ for treating metals and
"metallic ores by more perfectly washing and separating the metallic
"portions from the extraneous matters with which they are combined, I
"would have it understood that I do not claim any of the individual parts
" herein described, in so far as they shall have been heretofore applied and
"used for the same purpose and object as herein described, nor do I confine
myself to the precise proportions and configuration of the various parts of
"the apparatus which are delineated in the accompanying Drawings and
described in the reference thereto so long as the main features of my
"Invention are retained, as they may be varied to suit particular circum-
"stances without departing from the general character and principle of the
"Invention; but what I claim is,-
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page_text: Firstly, the application and use of perforated compartments or sieves, as
"herein described, or substantially so, arranged on the periphery of one or
"more concentric rims or wheels mounted on a horizontal axis and rotating
thereon vertically, or substantially so, in a reservoir of water in the manner
"herein described, or substantially so.
"Secondly, I claim the combination of the said rotary concentric com-
partments with one or more inclined tables and their accessories, either
"partially or entirely substantially as herein described, so as effectually to
separate one metal from another or the metallic portions of ores from the
"extraneous matters with which they are combined."
And I, the said William Prosser, do hereby further declare that the above
Disclaimer and Memorandum of Alteration are not nor is any part thereof
intended to extend the exclusive right granted by the said Letters Patent, and
that these Presents shall not extend the said exclusive right in any way
whatever.
In witness whereof, I, the said William Prosser, have hereunto set
my hand and seal, this Thirty-first day of August, in the year of our
Lord One thousand eight hundred and sixty-seven.
Temple,
JOHN B. KARS LAKE,
October 4th, 1867.
Attorney-General.

page_text: LETTERS PATENT to Robert Martin Roberts, of Dolgelly, in the County
of Merionethshire, North Wales, Mining Engineer, for the Invention of
"IMPROVEMENTS IN APPARATUS FOR TREATING METALS AND METALLIC ORIS."
“IMPROVEMENTS IN APPARATUS FOR TREATING METALS AND METALLIC Ori
PROVISIONAL SPECIFICATION left by the said Robert Martin Roberts
at the Office of the Commissioners of Patents, with bis Petition, on the
18th March 1865.
I, ROBERT MARTIN ROBERTS, of Dolgelly, in the County of Merionethshire,
North Wales, Mining Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR TREATING METALS AND METALLIC
ORES," to be as follows:-
My improvements relate to the washing and separating of metals and
metallic ores from the extraneous matters and substances with which they are
ordinarily combined, and consist of an arrangement of sieves or perforated
compartments on the periphery of one or more concentric wheels or rims
revolving vertically on a horizontal axis in a reservoir of water; the several
wheels or rims (when more than one are used) successively discharging their
contents into those which are outside them, until the whole of the combined
mass of material, whether alluvial deposits or ore previously crushed, has been
separated and cleansed from the extraneous matters and substances with which
the metallic portion is intermixed. In the case of crushed ores the coarser
and imperfectly crushed portions, which are too large to pass through the
sieves or perforations in the compartiments, are delivered by the rims into a

page_text: receptacle or receptacles, from which they are conveyed to the crushers by
travelling bands or other mechanical means, to be further crushed or pul-
verized and again passed through the separators. The subsident matter,
which is deposited in the bottom of the reservoir, is discharged therefrom by
scoops attached to the periphery of the revolving rims or wheels or otherwise,
and is transferred to sloping tables, on which the metallic portions are sepa-
rated and retained, while the extraneous matters are allowed to pass off to
reservoirs, in which any stray portions of metal may subside, the useless
matters running to waste with the current of water which accompanies them.
By these means I propose to perform the operations of washing and sepa-
rating metals and metallic ores more perfectly by recovering a greater portion
of the metals, as well as more economically by the diminution of manual
labour in the processes described.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Martin Roberts in the Great Seal Patent Office on
the 13th September 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
MARTIN ROBERTS, of Dolgelly, in the County of Merionethshire, North Wales,
Mining Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the 13th day of March, 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 Robert Martin Roberts, Her special licence that I, the said Robert
Martin Roberts, my executors, administrators, and assigns, or such others
as I, the said Robert Martin Roberts, 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 APPARATUS FOR TREATING METALS AND
METALLIC ORES," upon the condition (amongst others) that I, said Robert
Martin Roberts, my executors or administrators, by an instrument in writing
under his, 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

page_text: 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 Robert Martin Roberts, 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 :-
My improvements relate to the washing and separating of metals and
metallic ores from the extraneous matters and substances with which they are
ordinarily combined, and consist of an arrangement of sieves or perforated
compartments on the periphery of one or more concentric wheels or rims
revolving vertically on a horizontal axis in a reservoir of water; the several
wheels or rims (when more than one are used) successively discharging their
contents into those which are outside them, until the whole of the combined
mass of material previously crushed (whether alluvial deposits or ores) has
been separated and cleansed from the extraneous matters and substances with
which the metallic portion is intermixed.. In the case of crushed ores the
courser or imperfectly crushed portions, which are too large to pass through
the sieves or perforations in the compartments, are delivered by the rims into
a receptacle or receptacles from which they are conveyed to the crushers by
travelling bands or other suitable mechanical means, to be further crushed or
pulverized and again passed through the separators. The subsident matter,
which is deposited in the bottom of the reservoir, is discharged therefrom by
scoops attached to the periphery of the revolving rims or wheels or otherwise,
and is transferred to sloping tables, on which the metallic portions are sepa-
rated and retained, while the extraneous matters are allowed to pass off to
reservoirs, in which any stray portions of metal may subside, the useless
matters running to waste with the current of water which accompanies them.
By these means I propose to perform the operations of washing and sepa-
rating metals and metallic ores more perfectly by recovering a greater portion
of the metals, as well as more economically by the diminution of manual
labor in the processes described.
In constructing and working the apparatus I employ materials and driving
power suitable and convenient for the intended object. The wheels or rims
which form the body or framework upon which the sieve wire is placed may
be of wood or metal, or partly of both, as convenience may suggest, and of
dimensions suited to the quantity of ore to be treated. It will be found that
when the external diameter of the machine travels with a velocity of about 3 feet
per second sufficient traverse through the water will be obtained, and the
process satisfactorily carried out.

page_text: For general purposes I propose to construct the disc or wheel forming the
body of the machine of wood, and of about five feet in diameter, upon one face
of which I fix one or more concentric rims, and secure them to the disc by
suitable studs or brackets. To the periphery of these rims I attach wire or
other perforated strainers (by préference copper wire gauze of suitable mesh),
and I divide the rims into compartments of about three feet each in length, the
partitions being of a curved form (by preference), and formed of wire gauze
or perforated platė, so as to admit of the water in which the machine rotates
passing freely through the ores and cleansing it from extraneous matter, and
also to allow the water to drain away before the solid matter is discharged
successively from the compartments. Sufficient space is allowed between the
concentric rims or compartments to admit of the insertion of inclined aprons,
upon which the cleansed ore is discharged, and by which it is conveyed into
the receptacles provided for the purpose; or it may be delivered. on to tra-
velling bands, by which it is conveyed to washing tables for further treatment.
If the particles of the ore have not been sufficiently reduced in size for such
treatment the bands will convey them to the crushing machinery to be
further pulverized. The machine is fed with the material as it comes from
the crushing machinery at the innermost rim of the series upon which the
coarsest sieves or strainers are fitted, the other rims being fitted with sieves
or strainers increasing in fineness as they recede from the centre, so that the
ore in passing from one rim to another may be gradually separated from the
extraneous matters with which it is combined until the whole has been
cleansed. The refuse, together with the finest portions of the metal or ore,
The
are deposited in the tank or reservoir in which the machine rotates.
hopper and shoot through which the central series of compartments are fed
are placed at the side of the rim which descends into the water, and when the
compartments by the rotation of the machine successively arrive at the top
they discharge their contents on to the inclined aprons respectively, or on to
the travelling band. On the side of the disc opposite to that on which the
rims and strainers are fitted, and extending somewhat beyond the periphery
of the outer rim, scoops of suitable form, number, and size are arranged, sc
as to gather up the matter or matters deposited in the reservoir, the bottom
of which is suitably formed to lead the matter into them. Having raised the
deposit from the bottom of the reservoir to the highest point to which the
machine will elevate it, the scoops successively discharge it on to an inclined
apron, from whence it is conveyed, together with the water which accom
panies it, to a receptacle conveniently placed at the end of the reservoir, where
it is kept in a state of agitation by means of a rotating rake worked by a

page_text: band from the axis of the disc, in which state it is caused to flow either
through a perforated or wire gauze strainer, or over a weir on to an inclined
table, which may consist of one or more inclines as the ore to be separated
may require. On the first or upper incline I propose to use rakes placed at
intervals on a bar, to which a to-and-fro motion is given by a crank or
excentric on the axis of the rotating rake, by which movement the material
on the incline is separated and disturbed, so as to effect the more complete
detachment of the extraneous matter from the metallic portions of the ore.
It is apprehended that one set of rakes will be sufficient for the purpose in
ordinary cases; but should it be found necessary similar rakes may be applied
to another or all the inclines. The number and extent of the inclines will
depend upon the kind of metallic ore to be treated, and to the character of
the extraneous matter with which it is combined. In cases where the
extraneous matter is of a more adhesive character longer inclines or a greater
number of them will be necessary, and these may have means of adjustment
so as to vary the inclination if desired. The washed ore will be removed
from the inclines in the usual manner, the slime and other extraneous
matters passing off with the water into a reservoir, where it may be allowed
to subside for subsequent examination. It will be desirable to apply two
scoops for each compartment of the outer rim, and so to set them that
they will not commence discharging their contents until they arrive over
the apron, and also that they be entirely discharged before they pass the
apron, otherwise undue loss will ensue, which with the precious metals would
be objectionable.
For lead or copper ores where the extraneous matter is easily detached
from the metallic portions, it will be found convenient to adopt a simple form
of apparatus in lieu of the inclines, either in conjunction with or independently
of the rotating sieves; it consists of a concave fan or dish with a raised
wire or perforated screen on its edge, having a suitable gutter or channel
outside it for the purpose of receiving any portion of the water and matter
that may pass through the screen, and conducting it through a shoot or spout
to a suitable receptacle. I poise the pan or dish upon a ball-and-socket joint,
so as to admit of its receiving a rocking motion in every direction, which I
communicate to it by any convenient suitable movement. A graduated stream
of water is allowed to flow into the pan, and to escape by a suitable overflow
pipe, by which the extraneous matter is separated from the metallic portion
of the ore, and collected for subsequent examination in a tank or reservoir
contiguous to it.
The Drawings hereunto annexed will illustrate more fully the means by

page_text: which my Invention is proposed to be carried out, the Figures having letters
of reference denoting similar parts.
Figure 1 represents a front view of the machine; Figure 2 an end view of
the same; Figure 3 a back view of the same; Figure 4 a plan of the same;
Figure 5 a vertical section of the same, taken through the centre of the
machine.
A is the reservoir containing water, which may be stagnant or kept gently
flowing through at pleasure; B, the disc or wheel, upon which the rims C
are secured by studs D; E, the compartments on sieves, into which the metal
or ore is fed, and is successively transferred from one to the other; F, scoops
or buckets, which transfer the deposit from the bottom of the reservoir A to
the inclined apron G; H, the axis, on which the disc or which B is mounted,
working in carriages fixed on the edge of the reservoir; I, a band which for
communicating motion to the axis. Small machines only require manual
power to work them applied to a winch. K, a feeding hopper, in which the
crushed or pulverized material is deposited for feeding the machine; L, the
inclined aprons, upon which the matter remaining in the several compart-
ments after having passed through the water is delivered, and from which it
falls into a receptacle with partitions so arranged as to divide the different
products of the washing.
As the material in the original state in which it comes from the crushers
is fed into the centre series of compartments, so it may happen that some
portions of it may not be sufficiently pulverized, such portions may be carried
back to the crushing machinery by means of an endless band worked off the
axis of the machine. M, an inclined shoot for conveying the deposit raised
by the scoops to a reservoir N, in which a rotatory rake O revolves for the
purpose of preventing the subsidence of the material therein; the water and
material escapes or overflows through a perforated strainer, or over a weir or
waste board into a shoot, which conveys them to the inclined table P, whereon
the heavier is separated from the lighter matter, and the cleansing from extra-
neous matter being promoted by rakes Q on a bar R, which receives a to-and-
fro or reciprocating motion from a crank or excentric on the axis of the
rotatory rake O or the machine axis H. These rakes may also have a slight
cross motion to enable them to stir up the material more completely. Only
one series of rakes are shewn, as it is apprehended that they will be sufficient
for the purpose, but others may be used on the other tables, if found necessary
and desirable. S are reservoirs so placed as to receive the washings from the
tables, and cause them to flow under and over partitions placed therein, so as
allow the metallic portion of the matter flowing through with the water

page_text: to subside therein. Suitable mud doors at the bottom should be added for
getting ready access to the deposits. Figs. 6, 7, 8, sections and plan of
rocking pan or dish driven by crank T.
Having now described the nature of and the manner of applying and using
the improved apparatus which I employ for treating metals and metallic ores
by more perfectly washing and separating the metallic portions from the
extraneous matters with which they are combined, I would have it understood
that I do not claim any of the individual parts herein described, in so far as
they shall have been heretofore applied and used for the same purpose and
object as herein described, nor do I confine myself to the precise proportions
and configuration of the various parts of the apparatus, which are delineated
in the accompanying Drawings, and described in the reference thereto, so long
as the main features of my Invention are retained, as they may be varied to
suit particular circumstances without departing from the general character
and principle of the Invention; but what I claim is,―
Firstly, the application and use of perforated compartments or sieves, as
herein described or substantially so arranged on the periphery of one or more
concentric rims or wheels mounted on a horizontal axis, and rotating thereon
vertically or substantially so in a reservoir of water in the manner herein
described, or substantially so.
Secondly, I claim the application and use of a rocking pan or dish, as
herein described.
Thirdly, I claim the combination of the said rotatory concentric com-
partments with one or more inclined tables and rocking pan, and their
accessories, either partially or entirely, substantially as herein described, so as
effectually to separate one metal from another, or the metallic portions of ores
from the extraneous matters with which they are combined.
In witness whereof, I, the said Robert Martin Roberts, have hereunto
my hand and seal, this 13th day of September, in the year of our
Lord One thousand eight hundred and sixty-five.
Witness,
AMBT. H. RENTON,
5, Whitehall.
ROBERT MARTIN ROBERTS. (L.S.)