IMPROVEMENTS IN THE SEPARATION AND TREATMENT OF MINERAL SUBSTANCES, AND IN. COKING, AND IN APPARATUS CONNECTED THEREWITH
Year: 1856

page_text: 'LETTERS PATENT to Herbert Mackworth, ol. Clifton, in the County of
Gloucester, for the Invention of "IMPROVEMENTS IN THE SEPARATION AND
TREATMENT OF MINERAL SUBSTANCES, AND IN. COKING, AND IN APPARATUS
CONNECTED THEREWITH."
Sealed the 24th March 1857, and dated the 6th October 1856.
PROVISIONAL SPECIFICATION left by the said Herbert Mackworth at
the Office of the Commissioners of Patents, with his Petition, on the
6th October 1856.
I, HERBERT MACKWORTH, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN THE SEPARATION AND TREATMENT OF MINERAL SUBSTANCES
AND IN COKING, AND IN APPARATUS CONNECTED THEREWITH," to be as follows:
I break up shale containing.ironstone, and I separate them by means of
ascending or oscillating currents of water. I crush coal containing shale,
: pyrites, or impurities which have infiltrated from the soil, so as, without or
in lieu of sifting, to facilitate a more perfect purification of the coal and
a denser coke. I use
the production of
conical rollers,
or other rollers revolving at different velocities, for crush-
ing or pulverizing coal
and other minerals.
.
I .separate
granular
-mineral substances of different specific gravity, in a
or pulverulent state, by means of currents of water or air, which classify

page_text: or deposit them in the order of their dimensions, but so that the particles
of the heavier substances are smaller than the particles of the substances
of less specific gravity with which they are intermingled. I then sift
different portions separately, by which means I separate the heavier sub-
stances from the lighter ones; or I cause the washing and sifting processes
to be performed in one operation.
I communicate a rapid oscillatory motion or vibration to the current of
water or air used in separating mineral substances. I employ a conical
propeller with sloping or spiral vanes to propel water or air. I use a
reciprocating arm or blade to remove the fragments or grains of mineral.
The processes are varied somewhat according to the nature of the mineral
operated upon; thus, in operating upon ores containing native gold or
silver, I remove the larger particles of metal by means of an ascending
or oscillating current of water, and by sifting, and I separate the re-
mainder by a process of amalgamation, effected by the combination of the
machines known as the "Tyrolese mill" and the "riffle troughs." I pass
the grains of ore through narrow channels or pipes containing mercury,
or by pipes dipping into mercury, or I agitate them together through
sieves or plates, so as to bring the metallic particles in contact with the
mercury.
The water which is employed in operating upon coal is filtered, to
separate the fine particles of coal which are suspended in it; the coal
after being crushed and washed or purified, as aforesaid, is well adapted
for the manufacture of dense or pure coke. For this purpose I arrange
the heap or coking mound with a chimney or chimneys so constructed that
the products of distillation or combustion may be conducted to the bottom
of the chimney or chimneys, instead of entering at different parts of the
sides of the same. I connect two or more rows of chimneys together by
flues, and I employ moveable chimneys, when required. I carry an air
and
gas s flue along the bottom of the heap, and I also regulate the egress of
gas and admission of air at the sides of the mass. I conduct the gases pro-
ceeding from one heap, kiln, or oven, or from one flue, through another,
so as to ignite the coal or carbonaceous material and avoid loss of carbon;
I light the mass at top or bottom, or both, or in the interior of the mass;
and when the process is complete I extinguish the coke by means of steam
or carbonic acid gas. 'I add additional coal on the top, or at the ends or
sides, after the coal is ignited.
By means of transverse flues in or under the bottom of the coal, I pro-
duce, as required, an upward or downward action or currents of air and
gas, and by the connection of such flues with a chimney or stack, I produce

page_text: use mon sheets of perforated DICKS OF CHIES FOR covering the coal, utan
pipes for assisting the passage of air or gas through the coal, and chimney
pots or cowls for aiding the draught. I form the bottom of the kiln
or mass of coal on a considerable slope, which aids in the filling of the coal
or in the removal of the coke. In this manner I an enabled to produce a
comparatively pure and dense coke of good quality from an impure coal.
Similar arrangements are applicable to the coking or charring of peat and
wood.
SPECIFICATION.in pursuance of the conditions of the Letters Patent, filed
by the said Herbert Mackworth in the Great Seal Patent Office on
the 6th April 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HERBERT
MACKWORTH, of Clifton, in the County of Gloucester, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of October, in the year of our Lord One
thousand eight hundred and fifty-six, in the twentieth year of Her reign,.
did, for Herself, Her heirs and successors, give and grant unto me, the said
Herbert Mackworth, Her special licence that I, the said Herbert Mack-
worth, my executors, administrators, and assigns, or such others as I, the
said Herbert Mackworth, 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 THE SEPARATION AND TREATMENT OF MINERAL SUBSTANCES.
AND IN COKING, AND IN APPARATUS CONNECTED THEREWITH," upon the condition
(amongst others) that I, the said Herbert Mackworth, 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 Herbert Mackworth, do hereby declare

page_text: 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 thereof, reference being had to the accompanying
Drawings, and to the figures and letters marked thereon, that is to say:
The Invention consists of several different processes adapted to the
peculiar condition of the mineral operated upon, and the particular state
into which it is desirable to reduce it as a commercial article. In the
preparation of minerals' by existing processes there is an unnecessary loss,
the separation from impurities is not conducted with sufficient economy,
and the obtaining of a mineral in a greater degree of purity is hindered
or prevented by these defects. For example, coal as it comes from the
mine is mixed with shale or earthy matters and iron pyrites, some of which
are firmly incorporated with it. The presence of these foreign matters
prevents many seams of coal from being worked with advantage,, and.
renders many coals unfit for coking or very inferior for smiths' and similar
. purposes, besides producing a large amount of clinker and loss of heat-
ing effect when consumed under a boiler. Other minerals, such as copper
ores, are sent to the smelter in a very impure state, in consequence of the
agency of fire in smelting being found preferable to the inadequate modes
of separating or dressing ores now practised.
First Process. Some of the argillaceous strata, known under the
general term of shales, contain great numbers of small nodules of iron-
stone, frequently of a superior quality, which are now lost in consequence
of the cost of breaking them out and picking out the ironstone by hand.
It is not usually desirable to crush these ores and their matrices in the
same manner as ores ordinarily are by stamps, crushing rolls, &c., the
object being simply to break up the shale which surrounds the nodules
without injuring the latter.
Figure 1, Sheet I. of the accompanying Drawings, is a vertical section,
and Figure 2 is a plan of a machine adapted for this purpose. The lumps
of stone are allowed to pass down the inclined planes A, A', 'during
which descent they are subjected to the fall of the double row of stamp
heads B, B', which are set in motion by the rollers and cams C, C¹;
gearing into the driving shaft D. The stamps in the lower row are
opposite the intervals between those in the upper row, and the inclined
plane between the two rows tends to present the flat pieces of shale in
a different position to the lower stamps. The stones do not remain long
enough under the stamps to become pulverized, but simply fractured
in every direction. The fragments descending the shoot E enter by the
aperture F the separator G, which in operation somewhat resembles a pug
mill. The revolving arms or blades F, mounted on the vertical shaft I,

page_text: keep the whole mass constantly in agitation, and, aided by the action of
the water, further detach the shale from the ironstone. The piston J,
working in the cylinder K by means of the connecting rod L, keeps the
fragments in a continual state of vertical agitation. By means of the
valves j, j, opening downwards in the piston, a greater quantity of water
is driven upwards than is drawn downwards, thereby raising the mass in
the separator. The shale passes over by the shoot M, whilst part of the
water returns at each stroke by the perforated plate N, along the channel
O, to the top of the cylinder K. When a considerable portion of the
separator is full of ironstone, the door P is opened, and the flush of water
carries the ironstone out into an appropriate receptacle. Although
stamps heads are shewn in the Drawing as the means of fracturing the.
shale, other modes, such as heavy hammers, squeezers, &c., will readily
suggest themselves. An effectual and rapid means of producing the
same effect is presented by steam hammers, which may be substituted
for the stamps.
The rollers, represented in section in Figure 3,
and in plan in Figure 4, produce a similar result of breaking away the
shale round the nodules of ironstone without pulverizing them. These
rollers consist of fluted sections a, b, c, d, e, with the flutes or grooves
arranged alternately, so that the grooves in the sections a, c, and e are
opposite the projections in 6 and d, and the rollers are so placed that the
projections on one roller are opposite the grooves in the other roller:
When the shale consists of nearly pure argillaceous matter, such as the
fire-clay used for making bricks, the small nodules of ironstone which
deteriorate its quality may be separated economically, even where their
proportion is very limited. It is not necessary that the piston should be
provided with valves for the purpose before described, as, from the in-
clined surface of the blades H, and the conical form of the separator, the
mass of stone contained in it will gradually ascend. In lieu of the piston,
a continuous stream of water may be caused to run through the separator;
and over the shoot at the top, to effect the required separation.
Process No. 2. A large proportion of the seams of coal in this country
which lie near to the " "
crop or surface of the ground, called "crop coal,"
are left underground, or, if raised, are sold at a small price, in con-
sequence of the infiltration of clayey matters impregnated with iron from
the soil. By carefully crushing and washing the crop coal these im¹
purities may be separated, and a valuable fuel regained. In many seams
of coal bands of shale and pyrites pass into and firmly adhere to the coal,
and it is necessary to crush the fragments before they can be completely
removed. By reducing the particles of coal or other mineral to a more
uniform size, the currents of water or air can be regulated to a more

page_text: suitable velocity, and will effect a more complete separation of the
impurities.
Figure 5 is a vertical section, and Figure 6 is a plan, of a machine
adapted for this purpose. The coal or other mineral arrives by the shoot
A. The rollers B, B', are of unequal diameter, but geared together by
wheels C, C', of equal diameter, so as to cause the circumference of one
roller to move faster than the other This arrangement will cause the
particles or fragments to turn or roll as they pass through, and thus
presenting more than one side to the pressure will be crushed or torn
asunder along the weaker lines of division or fracture. Rollers are found
to wear into grooves or holes. To obviate this, the rollers shown in the
Drawing are made conical, to give the fragments a sidelong motion."
The rollers may be kept together by the ordinary lever and counter-
balance, to prevent fracture from the passage of hard pieces of stone or
other matter; or, as shown in the Drawing, strong bands of vulcanized
india-rubber D, D, may be placed round collars in which the axles work.
The india-rubber will then expand before the axles of the rollers break.
The difference in the speed of the two rollers may be effected
by making the toothed wheels C, C¹, of different diameters, in
lieu of making the rollers of different diameters. The mineral being
crushed descends on to the perforated plate E. Water is forced
up in a continuous stream through this plate, and through the
mass of mineral resting on it, by means of the fan or pump F. The
water descends again through the finely perforated plates G¹, G, G³, and
the trough II, to the fan or pump F. The current of water keeps the
particles in a state of agitation, during which the shale or heavier mineral
descends, and the coal or lighter mineral ascends. The arm I is made
to oscillate from side to side by the crank axle J, so as to push the lighter
mineral up the inclined perforated plates G1, G2, G3, and over the edge
of the machine on to the shoots K, K. This arm I partially presses the
water out of the mineral as it passes out of the machine. The bottom
of this arm may be provided with a strip of leather or a brush. By means
of a sliding plate L, moved by. the screw M, the size of the opening at N
can be regulated so as to provide for and regulate a uniform discharge
of the heavier mineral into the chamber O: Out of this chamber the
mineral is raised by the elevator P, and discharged by the shoot Q. In
order to bring the mineral more completely under the action of the water
it is fed from below, being made to pass under the sliding board R. S
represents the cylinder of the steam engine which works the machine; T
is a wheel or pulley on the crank shaft of the engine, which gives motion
by means of a strap to the small pulley U on the axis of the rotary pump

page_text: axes.
or fan F. A pinion on the crank shaft drives the wheel V on the axis
of the roller B. In order to impart a rapid oscillating or vibrating motion
to the water, a valve or vane W may be fixed to a shaft, which, by means
of a forked lever X, and an excentric on the axis of the fan, will partially
close the opening at every revolution of the fan. A less rapid motion
may be communicated by connecting the lever with one of the other
The same result may be effected in many other ways without
rendering it necessary that the current of water should at any time be
reversed. By covering over the top of the machine with
canvas or other suitable covering, a current or currents of air may be
employed in lieu of water, or they may be employed in combination with it.
To propel currents of water or air, I employ the revolving fans or pumps
represented in Figures 7, 8, 9, and 10, and which, by the principles of
their construction, obviate some of the losses of power inherent to the
employment of ordinary fans. The propeller, represented in plan in
Figure 7, and in section in Figure 8, has two or more sloping or spiral
vanes A, A. These are so arranged as not to deflect unnecessarily from
the straight line the particles of water or air passing through. The
enlargement of the upper part of the cone allows the particles to pass or
expand into the direction communicated by the centrifugal action of the
fan, and the area between the vanes at B, where the air enters, is made
larger than the area at the points of exit C. By this arrangement the
air is not throttled. The same remarks apply to Figures 9 and 10, which
represent the plan and section of another form or modification of the
preceding fan; the vanes may be made either straight or curved in the
manner shown. By altering the proportions of the length and diameter
of the propellers, they can be made to take a greater or less hold on the
air or water, so as to yield a greater or less propelling force, in proportion
to the velocity, and they can, therefore, be constructed so as to suit the
kind of work which they are intended to perform.
Third Process-The machine represented in longitudinal section in
Figure 11, Sheet II., in transverse section in Figure 12, and in plan in
Figure 13, is so arranged as by sifting the fragments and grains simul-
taneously with the washing, to submit them to currents of water, whose
velocity is so regulated as to produce a more perfect separation of the
impurities; it is particularly applicable when the mineral to be operated
on is very friable. The chief difficulties in the processes of washing, and
the principal loss of good coal, have hitherto arisen from the large propor-
tion of coal dust, especially after the coal has been crushed by rollers.
When large coal is crushed, it should be passed through two pairs of
rollers, the first pair being erected with a considerable space between

page_text: them. The proportion of shale dust mixed with the coal dust is com-
paratively small; the finer particles and dust are removed by allowing
the coal or other mineral, as it comes from the rollers or an elevator, to
descend a. shoot A, across which are placed the bars B and the bars C,
to separate and distribute the grains as they fall past the opening D
which communicates with a chamber E¹, E. An inward draught or
current of air is produced by connecting the chamber E with a stack or
chimney, or other means of producing the required current by the pipe F:
It is desirable that the current of air should be nearly uniform. The
larger particles of coal dust, or lighter mineral mixed with lighter
particles of shale dust or the heavier mineral, fall in the first compartment
of the chamber E'; the still lighter particles fall in the second com-
partment E; they are removed by appropriate sliding doors G,
round which should be hung or nailed a cloth before the contents of
the chamber are permitted to fall out. Steam from a pipe may be
employed, with air to blow the dust into the chamber, and steam or fine
rain may be used in the chamber to precipitate the dust more quickly
and completely. Sieves placed transversely across the chamber will also
expedite the process. When required, the fine grains and dust thus col-
leted may be submitted separately to the sifting or washing processes
described in these Presents. Coal dust thus separated may, unless the
coal is very impure and the shale and pyrites unusually friable, be con-
veniently mixed with the other washed coal, so as to reduce the per-
centage of water of the whole mass to a degree suitable for the supply
of the coking ovens. The remainder of the minerals which descends the
shoot enters the first chamber H of the washing machine, falling on to the
perforated plate I. By means of the double cranked shaft J, an upward
and downward motion of the piston K is produced, which causes the water
to rise and fall through the mass of mineral before mentioned. The
bottom of the piston (being provided with valves, through which, during
its ascent, the water passes freely, the descending currents of water in the
mineral are comparatively slight as compared with the ascending or lifting
currents. The effect of this, aided by the width of the upper part of the
chamber B, is to raise the mineral. up to or nearly to the level of the
endless band of wire gauze or cloth L. As the grains of mineral rise and
fall, the smaller grains pass through the perforated plate or gauze M into
the second chamber N, in which the currents of water are made to flow
at less velocities than those in the first chamber, being proportioned, in
fact, to the sizes of the grains which will pass through the sieve M. If
any small particles of shale, for example, find their way to the upper
part of the first chamber, in lieu of being carried off along with the larger

page_text: pieces of coal, they will find their way into the second compartment, and
under the diminished current work their way to the bottom. The water
flowing through the sieve M aids the passage of the particles. The shale
or heavier mineral gradually extends along the bottom of the two
chambers into the recess O, where, from the bottom and end being per-
forated, it is subjected to a more thorough penetration and action of the
water, so that no particle shall escape its action. The heavier mineral
is discharged by the openings and sliding valves at P, regulated by the
screws Q, into the chamber R, from whence (by first closing the valves
at P) it can be discharged by opening the door S. Before again opening
the valves P, water should be allowed to enter, to fill the vacant chamber,
by means of a pipe or other contrivance. As the currents of water in
the chambers H and N ascend at each complete stroke of the piston more
than they descend, the water is continually rising through the fine endless
sieve L, and then flowing across it falls into the channel T, into which
water also enters through the very fine sieve or cloth U. Both of these
sieves being exceedingly fine filter the water of much of the lighter
particles floating up with it. The longitudinal brushes b, b, b, against
which the endless sieve L is continually pressed by the straight edges
c, c, c, tend to prevent the particles passing between the partitions or
divisions and the endless sieve; this endless sieve L, having motion com-
municated to it from the cranked shaft J by the wheels V, W, carries
on its exterior circumference one or more blades a, a, of iron, mounted
on a stout strip of leather, which is attached to the sieve or otherwise;
made with a certain degree of elasticity, or rigid blades may be used;
these blades carry forward the lighter mineral on the surface of the mass
in the chambers H, N, until they reach the curved plate X. The interval
between the sieve and the plate being somewhat contracted toward the
upper part, the mineral is subjected to pressure after leaving the water,
so as to aid in partially freeing it from water before it is delivered to
the shoot Y; any fine grains or silt which may have collected on the inner
surface of the endless sieve are pressed through it again as it goes over
the roller Z, and it falls also on to the shoot Y. The blade or blades a
return to the other end of the machine over the rollers Z, Z', and again
travel over the chambers H and N, removing the fragments or grains of
mineral as before, and thus reciprocating from end to end of the machine.
The water returns by the channel T on to the upper part of the piston K.
If any further filtering of the water in its return to the piston is required,
this may be effected by allowing it to pass through a sponge in the usual
way; and by pressing the sponge occasionally, to remove the slimes, either
by hand or by machinery; the velocities of the currents in the second

page_text: chamber N may be diminished, and regulated by contracting the opening
d, and by employing a plate i in the bottom with smaller perforations.
A continuous stream of water, in lieu of an oscillating one, may be also
applied to this as well as to the last machine, or they may be used in
combination. In all washing machines a constant supply of water is
required to replace. the water aborbed by and delivered over with the
minerals, as well as to meet the other sources.of waste.
Fourth Process.-It is found in operating upon coal with currents of
water that the lighter particles which are suspended in the water are
frequently of excellent quality, and that it is desirable to regain them.
Letters Patent were obtained by me, the said Herbert Mackworth, dated
31st July 1855, for a machine worked by a. circulating stream of water,
but as a small portion of the floating particles of coal might be carried
down by the shale or settle in the chamber with the impurities, the form
of machine represented in section in Figure 14, Sheet II., and in plan
in Figure 15, has been preferred. The coal, when required, is passed
through one or more pairs of rollers, and is raised by the elevator A, so
as to be regularly supplied to the revolving hopper B. The separator C
is thus kept supplied with coal, through which passes, by means of a
revolving fan or pump D, or other means, a continuous or intermittent
current of water. The shale gradually descends on to the perforated
plate E, whilst the pure coal remains in the upper part of the separator C,
and is pushed, by means of the curved arm or blade F, over the edge of
the machine on to the shoot G. The water passes, slightly filtered,
through the perforated plate or gauze H, and to prevent the holes in this
becoming clogged with the slimes, a brush I, adjustable by set screws,
follows the curved arm, and also pushes a portion of the slimes up the
sloping perforated plates H. The shale passes out of the separator by
means of the valves J, and is pushed through the openings by a recipro-
cating arm or arms driven from the exterior by a horizontal rod passing
through stuffing boxes or other means, or by means of the arm or blade K,
attached to the shaft K. The openings of the valves are adjusted by the
spindle and wheel L. The shale collects in the chamber M, and by first
closing the valves J, this chamber can be emptied without stopping the
machine by means of the door N. On closing the door again, the chamber
M should be filled with clean water from the pipe O, as otherwise on again
opening the valves J it would become filled with water containing coaly
matter, which would eventually be deposited amongst the shale. Whilst
the valves J are closed the shale collects in the bottom of the separator C.
The water, after passing through the perforated plate or gauze H, passes
through the pipe P, and enters by the sliding door Q the first compart-

page_text: ment R of the filtering cistern. The fine gauze S arrests the scum float-
ing on the surface of the water. The water next has to pass across the
brush T, to prevent this brush filter becoming clogged, another inverted
brush or scraper U is attached to the sliding rod V, which rests against
the spring W. Each time that the curved blade F revolves, it presses
against the bar X, and compresses the spring W. As soon as the blade F
has passed, the spring W throws the rod V quickly back, and causes-the
scraper U to clear the brush T; these brushes may be altogether below the
surface of the water. In the second compartment R there is a similar
arrangement at T', the scraper U being also attached to the rod V. At
Y and Yi are placed, on the top of the divisions, two thin plates or knife
edges; as the water supplied to the cistern flows slowly onwards, the
particles subside, and this thin edge producing little or no disturbance of
the water, slices off or separates the comparatively pure upper film of
the water, allowing the fouler portions to subside in the compartment:
To promote the more rapid subsidence, hammers a, a, are hung on the
outside of the second and third compartments R', R, of the cistern,
against the side of which they strike at short intervals, and cause a slight
vibration of the water inside, which is found favorable to the deposition;
one of these hammers is shewn in Figure 16. A screw b, on the shaft
of the revolving pump D, works the toothed wheel c, mounted on the
shaft d. Two cams e, on this shaft, alternately raise and drop each
hammer a. The orifice of the discharge pipe f is surrounded with a fringe
of fibres or bristles g, still further to arrest the lighter particles in the
water. The deposit in the compartments R, R1, R2, of the cistern is
emptied by opening the doors h, h¹, h; whilst the first compartment R
is emptying, the sliding doors i and j are opened; and Q is closed; whilst
the second compartment is being emptied, the doors Q, k, l, m, are opened,
and and j are closed; the third compartment will only require to be
emptied occasionally, but when necessary the fine slime may be drawn
off from it by a tap, or the machine may be stopped while it is emptied
by opening the door h². The principal object of this filtering process is
to prevent the coaly particles in suspension in the water' from being
again passed up through the shale in the separator C, and so finding their
way into the shale chamber M. The loss of coal which would arise from
this source is small; and passing the water through vertical or inclined
fine wire gauze, or through sponges or other suitable filtering media which
can be quickly cleaned, will also effect the desired object to a considérable
extent. It will sometimes be convenient to let the water pumped from
a mine or from some head of water flow into the machine by the pipe n,
and leave it by the pipe P, in which case the water may be filtered, if

page_text: required, by passing it through gravel, or by the other modes adopted
for filtering water. When a good deal of clayey matter is present in the
coal and impregnates the water, the water will have to be more frequently
renewed. The water can be discharged by a cock on the pipe f, and the
fresh water supplied into the separator C, or in any other convenient part
of the apparatus. In operating upon metalliferous ores this machine may
be used with or without the filtering cistern. In washing any description
of mineral, the pump may be removed and water allowed to flow from
a small head through the pipe n, and to discharge itself by the pipe P,
either to waste or into a filtering apparatus.
Fifth Process. When mineral substances in a granular or pulverulent
state have been subjected to the action of currents of water in machines
having an uniform action, the particles are assorted more or less perfectly,
according to their size, shape, and specific gravity. It will generally be
found, on examining any portion of mineral so acted upon, whatever may
have been the uniform direction or force of the current of water, that
the grains of a heavier substance are smaller than those of the lighter
substance with which they are intermixed; by submitting them to a
sifting operation, the two minerals may be to a great extent separated.
For example, Figure 17, Sheet I., represents a common buddle, and
Figure 18 a round buddle; if the mineral in the first be divided into
several parts 1, 2, 3, 4, 5, 6, and in the second into annular portions 1, 2, 3,
each of these parts may be sifted separately in ordinary sieves working
in water, and having a vertical or centrifugal or reciprocating motion.
Figure 19, Sheet I., represents the section, and Figure 20 a plan of a
suitable sifting apparatus. It consists of an inclined cylinder A, covered
with perforated plates or wire gauze partially immersed in water, and
provided on the interior with plates B, arranged like an Archimedean
screw. The mineral is supplied through the shoot C. The cylinder may
either be covered with perforated sheets or wire gauze of the same
degree of fineness, or there may be several degrees of fineness, the
smallest holes being towards the lower part of the cylinder, and the
larger holes towards the upper part. In the latter case, each of the com-
partments D. will contain the heavier mineral mixed with a different
proportion of the lighter mineral, but in a favorable condition for further
operations, if needed. The long distance which each particle has to
travel in traversing this cylinder ensures a superior degree of sifting. The
cylinder is worked by the handle or crank E, and can be lifted out when
the compartments D are to be emptied, or the latter can be made to
discharge themselves by doors or similar contrivances.
Sixth Process. The machine represented, in longitudinal section in

page_text: Figure 21, Sheet I., in transverse section in Figure 22, and in plan in
Figure 23, combines the operations of separating by water and by sifting.
The chest A has another chest inside it, of which the sides are marked
B and the bottom C. This inner chest is divided into five compartments
by the partitions D', D2, D3, D', which extend from the bottom nearly to
the top. Each of these five compartments is again divided into two by
the partitions E', E, E³, E', E³, which extend from the top nearly to the
bottom of the compartments F', F, F, F, F, which gradually increase in
size, and each of which is larger at the top than at the bottom. Water
is made to flow in regular quantity down the trough G in the direction
of the arrows. The current of water ascending each of the compartments
F, F, F, F, F, is gradually diminishing in velocity in consequence of
the increased area of the channel. Minerals in a finely divided state are
brought by the water down the shoot G. The teeth or points H on the
shaft I, moving from side to side, break up the grains which are clotted
together, and they flow on with the current of water; the heaviest grains
will be found deposited in the bottom of the first compartment F', the
next heaviest in the next, and so on, and where two substances of different
specific gravities are found together, the grains of the heavier will be
smaller than those of the lighter substance. Each particle is in fact
weighed by the ascending current, and deposited in a regular ratio, which
is a compound of shape, size, and specific gravity. To remove these
grains as they accumulate, openings or slits J are left on each side of the
inner chest, and the rocking arms K, fixed to the shaft I, push a small
portion of the mineral at each oscillation through the holes J; the grains
thus falling through drop on to the sieve L, which, being suspended
by the arms M from the shaft 1, also rocks with the arms K. Pieces of
leather N are fixed to the bottom edges of the inner chest, and as the
sieve passes and repasses, distribute the grains over the sieve so as to
enable them to pass through; the vibration caused by the sieve knocking
at each oscillation against the outer chest facilitates the sifting. The
portions that fall through the sieve fall into the centre compartment of
the trays O; the portions that are pushed by the leathers M over the edges
of the sieve L fall into the outer compartments P, P, of the trays; the
trays can be removed by opening the door Q. There is no sieve under the
first compartment F', as the grains lodging in that compartment will be
(if the supply of water has been properly regulated) almost confined to
the grains of the heaviest mineral to be separated. Each portion of the
sieve is made successively of finer perforated plate or gauze, in order to
restrict as far as possible the passage through the gauze, and the con-.
sequent collection in the central trays, to the mineral of greatest specific

page_text: gravity. When native gold or silver is operated upon, mercury can be
placed at R, below the level of the apertures J, J, and also in the central
trays, to amalgamate with and collect these metals. The water flows off
by the shoot S, together with the slimes, which require the employment of
other means to deposit and separate them.
Seventh Process.-Figure 24, Sheet II., represents the section, and
Figure 25 the plan of a machine for amalgamating and separating native.
gold and silver. The slimes issuing from the last machine may be allowed
to flow into it, or it may be supplied at once with the finely pulverized
matrices which contain these metals. The mineral flows with the water
by the shoot A into the mill B, the inner basin or portion of which,
marked B', as well as the portions C', D', E', of three other mills C, D, and
E, is kept revolving, motion being communicated from the strap F. The
minerals arriving by the shoot A descend the vertical pipes b, b, b, b, b, b,
which are of different diameters, according to their distances from the
axis, and the grains are brought at once into contact with the mercury
by which the bottom of this as well as the other mills is covered. Slightly
above the lower orifices of the pipes b, b; is a disc of iron wire gauze or
perforated iron plate c, through which the grains must rise in order to fill
the outer and fixed basin of the mill B, in which they are kept in constant
agitation by the revolution of the pipes b until they escape by the shoot G,
which conducts them to the second mill C. The particles descend
between the inner revolving portion C" and the conical bottom of the outer
fixed basin C. The iron ring or hoop d obliges the particles, as they pass
underneath it, to come into contact with the mercury, the surface of which
is kept in a continual state of agitation. The particles which cannot be
carried up by the current of water between the revolving and the fixed
case collect in the enlargement e of the fixed basin, where they are kept
in constant motion and revolution by the current of the water. Amongst
these will be some of the larger particles of gold and silver, which will be
thus more certainly absorbed by amalgamation; the current of water and
minerals carried along by it pass into the mill D by the shoot H, which is
almost identical with the ordinary form of the Tyrolese or Hungarian
mill, except that the bottom of the revolving portion (in lieu of fixed
blades) is furnished with trailing plates f, made either of perforated iron
or.iron wire gauze; these bring the heavier particles with greater certainty
into contact with the mercury. The minerals are carried up by the
water, as in the last mill, between the revolving and the fixed portions,
and then descend the shoot I into the basin E, in which the trough J is
stationary and fixed to it. As the shaft K revolves by means of the

page_text: strap L, the curved under surface of the wheel M, sliding over the stud or
fixed point N (on which it is allowed to press), has an upward and down-
ward motion communicated to it as well as the motion of rotation. This
double motion is communicated to the light iron sieve E¹, fixed by a
frame to the bottom of the shaft, and causes it at intervals to press into
the surface of the mercury as it also revolves, and thereby to distribute and
intermix with the mineral matters the particles of mercury which pass
through the sieve, besides pressing the heavier grains (which tend always
to collect near the bottom) into the surface of the mercury at all points.
The mineral matters, mixed with particles of mercury, pass up between
the trough J and the outer basin E, and descending the shoot O, are dis-
tributed equally over the whole width of the rifle troughs P of the
ordinary description, in the bottom of each of which is a small quantity
of mercury. These troughs perform the double office of further arresting
and amalgamating particles of the gold or silver, and also of partly collect-
ing the minute globules of quicksilver which pass over from the previous
processes; this is continued by the narrow troughs Q, in which are placed
small partitions g, g, which retain the mercury in them. In consequence
of the shape of these troughs, the stream cuts channels through the sand
collecting on the mercury, and deposits the heavier grains in the bottom.
After leaving the troughs Q, the mineral matters overflow on to the
blankets R, which are applied in the usual way to further arrest the
particles, and especially the thin laminæ of metal which may have escaped
the previous treatment. One of the reasons of the great loss of the
precious metals in the ordinary modes of amalgamation with currents of
water is attributable to the varied size and shape of the metallic particles,
and it is only by varying the action of the water as much as possible, as
well as the mode of agitating the grains, that these natural peculiarities of
size and shape can be turned to account. It will sometimes be found
better to employ these mills in a different order to the one shown in the
Drawings, or one or more of them may be used separately. If the iron
pans of the mills are moderately heated by flues passing under them
or other means, a more rapid amalgamation will be effected. The
mercury may be either run off by holes in the bottom of the pans, or may
be removed after first lifting out the inner basin or trough; and the gold or
silver is removed from it in the usual way, by pressing it through a leather
or cloth, or by distillation. The handle of the machine represented in
Figures 21, 22, and 23 may be connected by a connecting rod S directly
to the crank axle T, so that both machines may be driven by the main
strap F.
Coking. In coking coal and other matters, whether in heaps, kilns, or

page_text: ovens, the principle has to a great extent been lost sight of that the princi-
pal objects of the coking are, besides the agglomeration of the fragments,
to remove the greater part of the small per-centage of hydrogen in coal,
and to inipart to it at the same time a degree of porosity suited to the
purposes to which it has to be applied, and that in effecting these objects
as little carbon as possible should be allowed to escape with the hydrogen
in the form of gas, and as little carbon as possible should.be.consumed in
producing that degree or continuance of temperature which is necessary
to effect the distillation of these gases and attain the required quality of
coke.
The improvements proposed on the ordinary system of coking in heaps
which in many instances, owing to the character of the coals and the coke
required, has been pursued in preference to employing ovens or kilns, are
represented in plan in Figure 26, Sheet II., and in section in Figure 27.
The chimney A is provided with openings a, a, at the bottom; the coal
(which is better if entirely small) is filled in up to the level of these open-
ings, and the largest pieces of coal should then be built on the top of this
layer, so as to leave as may interstices as possible communicating with the
holes a, a; or, in case small coal has alone to be coked, flues b, b, may be
built in the mass of the coal in directions radiating to the openings a, a;
these flues or air passages may be built with oblong pieces of coke or damp
small coal rammed in moulds, or with perforated pipes, bricks, or pieces of
sandstone. The fire may be lighted by throwing on lighted coals at the
points B, B; and gradually covering them up with other coals to about
'the level C, C. The air then draws into or through the coal, and decom-
posed in passing through the heated masses; it passes with the other pro-
ducts of distillation by the flues b, b, or openings a, a, into the chimney A.
"As the coking in the lower part proceeds, the fissures in the coke itself
offer a greater facility for the passage of the gaseous products between the
incandescent surfaces of these fissures. As the coking ascends, fresh
layers D, E, of coal are added on to the top by tipping it over the walls
F; F, or by other convenient means; these walls serve also to retain the
heat, and in case the coal is very dense, pieces of large coal may be laid
alongside of them to allow the air and gases to pass more freely down.
wards. The principal advantages arising from the filling of the coal at
successive periods are that the air more readily permeates the mass,
especially if of small coal, so as to reach and sustain the combustion going
on-below. The thickness of the layers depends on the size of the particles
of coal, and the rapidity of the coking may also be regulated by the thick-
ness of the layers thrown on. If the coking ascends too rapidly in any part,
small coal is immediately thrown on at those parts to increase the thick-

page_text: ness of the layers, and if it ascends too rapidly in the part near the
chimney, a damper is made partially to close the top of it, and some water
may be thrown on the coal itself. The small coal beneath the level of the
openings a, a, is coked by the heat and radiation from above. Great
depths of coal may in this manner be coked. When the coking is nearly
reaching the top of the heap, iron plates or perforated bricks or tiles may
be laid on; and fine coal or coke dust may be thrown on in the usual way
to damp the fire. The ends of the heap may be inclosed partially by walls
or, simply covered with similar fine dust, through which air penetrates.
One or more chimnies may be employed in one or more rows, and the heap
extended; the coal at one chimney may be lighted from the coal at the
next, already in a state of ignition, by closing, or partially so, the latter,
and letting the products of combustion find their way through to the
chimney to be set in operation. This may also be effected by a per-
manent flue G, connecting the bottoms of the chimnies along the bottom of
the heap, the openings into the chimnies being ordinarily kept closed by
dampers H, which can be raised up the chimney by a rod and lever, when
required; this longitudinal flue G will also serve to introduce air to burn
the
gases in the chimney itself. The draught of the chimnies is aided by
moveable chimney pots or cowls. Each chimney may be divided by one
or more vertical partitions, so that each division shall communicate with
and convey the gases from separate portions or sections of the surround-
ing coal When the coal has been coked, or nearly so, the damper is put
on the chimney, and the coke is either allowed to cool, or is quenched by
pouring water on to it. It can be removed from the heap in the usual
manner.
Coking in Ovens.-Figure 28, Sheet II., is a longitudinal section, and
Figure 29 is a transverse section, of an improved coke oven. Flues A, A,
B, B, are built in the brickwork, opening out of the oven at some distance
above the bottom, and passing down underneath it to the other side of the
oven; they ascend in chimneys A', B', which communicate with the
longitudinal sloping flues C and D, which have openings communicating
with the external air. These flues remove the gaseous products from the
coal as it cokes, and render the heat available in keeping hot the interior
of the oven. The oven is covered by a flat covering of iron or other suit-
able materials, or by an arch E, and the air is allowed free access to the
upper part of the coal by the filling place F. The door G having been
closed, (coal, which may be entirely composed of small,) is thrown or
tipped in from the hole F, or other convenient filling places. It is raked
to a uniform height above the holes of the flues A, B, by a rake passing

page_text: over the top of the door G. From six inches to two feet above the level
of the flue openings A, B, according to the size of the coal, may be thus
filled in, and the coal may be ignited by throwing in burning coals by the
feeding place or over the door G, and the feeding place F and the upper
door H being then temporarily closed, the coal will ignite, and the
draught be set in motion through the flues A, B, on each side of the
oven. A small quantity of air should be allowed to enter the oven to assist
the ignition, and when this has proceeded through the length of the oven,
a fresh charge of coal can be thrown on the top, and brought to a uniform
slope by opening the door H and the application of the rake. The coal
may be ignited by the heat of an adjacent oven, and to effect this more
rapidly, some of the flues, instead of passing. under the same oven, may be
built to pass under the next one. As the coking proceeds, the air, as in
the case of the heap, draws downwards, entering by the charging place
or the opening left by the upper door H, and the products of combustion
pass off by the flues A, B. The coking descends from the openings of the
flues A, B, through the mass of coal to the bottom, and it also ascends from
these openings towards the top of the coal above them, and as it ascends
fresh layers of coal are charged and spread on the top; the door H being
let down and closed when the surface is above the level of the lower door.
An opening is however left in the upper door H, for the introduction of the
rake. A great depth of coal, amounting in some cases to eight feet, as
high as the springing of the arch, may thus be coked. The products of
distillation passing through the interstices of the heated coke below.
deposit a portion of their carbon, so as to limit greatly the escape of any
other gases than those which contain the smaller proportions of carbon.
Whenever any of the vertical chimnies draw too quickly, or give off much
flame, they are closed by dampers I and J. If the coking proceeds too
rapidly on one side of the oven, the chimnies which draw from that side
may be thus closed, and the other chimnies being open, may also be made
to draw along the ascending flue C or D, and into the chimney M, so as
to take advantage of its draught by covering the openings on this ascend-
ing flue by flat covers K'or L. When the coking has nearly reached the top
of the mass, the charging place F and the door H are carefully closed,
and in order quickly to bring the upper part of the coke to a somewhat
similar degree of hardness to the lower, communication is made at N with
the chimney M, or other exhausting stack, and the heat and gases are
allowed to draw upwards through the coke. The coke may be quenched
with water introduced by the charging place F and the door H, or it may
be removed, and then quenched in the usual modes. To facilitate the

page_text: filling and removal of the coke, the oven has been shown as built on a
slope, but it may be also made on a level. O, P, are passages for cleaning
out the flues, which passages are ordinarily closed by plugs or stoppers set
in mortar. The coke may be cooled in the oven by closing the apertures
and introducing steam by a pipe.
Having now described the nature of my said Invention, and in what
manner the same is to be performed, I wish it to be understood that what
I claim is,-
Firstly, the separating or extracting of nodules of ironstone from shale
containing the same, by breaking up the shale and submitting it to an
ascending current or currents of water, in manner herein-before described.
Secondly, constructing machinery for crushing minerals with conical
rollers of equal diameter so arranged and connected as to revolve at
different velocities, or with unequal conical rollers so arranged as to
revolve at equal or unequal velocities, as herein-before described;
Thirdly, constructing machinery for separating minerals of different
specific gravities with a reciprocating arm or a blade or blades so arranged
as to remove the lighter mineral from the upper part of the same chamber
in which the separation is effected by the action of an ascending current
or currents of water, as herein-before described in reference to Figures
5, 6, 11, 12, and 13.
.
Fourthly, the communicating of a rapid oscillatory movement to the
ascending current or currents of water or air, or both, when used for
separating mineral substances, but so that the current or currents do not
descend through the mass of minerals operated upon, as herein-before
described in reference to Figures 5 and 6.
Fifthly, the application of a current of air for removing or separating
the lighter particles of the dust of mineral substances previously to the
purification of the remainder, in the manner herein-before described in
reference to Figures 11, 12, and 13.
Sixthly, the shifting of the particles of minerals simultaneously and in
the same chamber with their purification by ascending.currents of water,
as herein-before described in reference to Figures 11, 12, and 13.
Seventhly, the separating the fine particles of coal or other mineral
from the water employed in purifying it, by causing the water to filter
through an endless band of wire gauze, or through brushes, or to flow
over the thin edges of plates, with or without the aid of hammers to pro-
mote the separation, as herein-before described, and shewn in Figures
11, 12, 13, 14, and 15.
Eighthly, the purification or separation of minerals of different specific

page_text: gravities by submitting them to the action of a uniform current or currents
of water, and then sifting the different portions separately, as herein-
before described in reference to Figures 17, 18, 19, and 20, and Figures
21, 22, and 23..
Ninthly, the treating minerals containing gold or silver by amalgamation
in the same vessel or apparatus, and simultaneously with the water separ-
ating and sifting process, as herein-before described in reference to
Figures 21, 22, and 23.
Tenthly, the amalgamating of gold and silver by means of the mills in
combination with the narrow troughs, and the moveable sieves or plates,
by which the particles are brought in contact with the mercury, as herein-
before described in reference to Figures 24 and 25.
Eleventhly, the combination of machinery and apparatus herein-before
described, and shewn in Figures 1 and 2.
Twelfthly, the combination of machinery and apparatus herein-before
described, and shewn in Figures 5 and 6.
Thirteenthly, the combination of machinery and apparatus herein-
before described, and shewn in Figures 11, 12, and 13.
Fourteenthly, the application of a reciprocating or moveable arm or
blade to remove the fragments of shale or heavier mineral from the
separator, as herein-before described in reference to Figures 14 and 15.
Fifteenthly, the combination of machinery or apparatus for separating
the fine particles of coal or other mineral from the water, as herein-before
described, and shewn in Figures 14 and 15.
Sixteenthly, the combination of machinery and apparatus herein-before
described, and shewn in Figures 21, 22, and 23.
Seventeenthly, the combination of the mills with the riffle troughs, as
herein-before described, and shewn in Figures 24 and 25.
Eighteenthly, the coking of coal by charging it in successive layers
added during and so as to regulate the coking process round one or more
chimnies, having a series of openings at the bottom of the chimney, or at
a level somewhat above the bottom of the mass of the coal, as herein-before
described in reference to Figures 26 and 27.
Nineteenthly, the constructing coke ovens with flues opening out of the
sides of the oven below the surface of the mass of coal to be coked, and
carried under and up the opposite side of the oven, or partly round an
adjoining oven, to economize the heat and produce an adequate.exhaus-
tion of the gaseous products, so that the coking may be further regulated
and continued by charging successive layers on the surface of the mass, as
herein-before described in reference to Figures 28 and 29.

page_text: I also claim the completing of the coking process by causing the currents
of air or gas to reverse and draw upwards through the coke by means of
a chimney or other exhausting power, as herein-before described.
In witness whereof, 1, the said Herbert Mackworth, have hereunto
set my hand and seal, this Fourth day of April, in the year of our
Lord One thousand eight hundred and fifty-seven.
HERBERT MACKWORTH. (L.S.)
HERBERT MACKWORTH. (L.S.)
Witness