IMPROVEMENTS IN MACHINERY FOR PURIFYING FLOUR AND MIDDLINGS
Year: 1879

page_text: LETTERS PATENT to Moses Lyon, of King's Cross, in the County of Middlesex,
for the Invention of "IMPROVEMENTS IN MACHINERY FOR PURIFYING FLOUR
AND MIDDLINGS." A communication from abroad by Andrew Hunter, of
Rochester, New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Moses Lyon at the Office of
the Commissioners of Patents on the 15th January 1879.
MOSES LYON, of King's Cross, in the County of Middlesex. "IMPROVEMENTS IN
MACHINERY FOR PURIFYING FLOUR AND MIDDLINGS." [A communication from
abroad by Andrew Hunter, of Rochester, New York, United States of America.]
This Invention relates to improvements in machinery for purifying flour and
middlings, and consists in various details of construction hereinafter described,
whereby much better results are obtained than have been possible with machines
heretofore constructed for the purpose.
In carrying the said Invention into practice I provide wind-compartments near
the bottom of the machine, with apertures along their sides, through which aper-
tures the blast enters the chamber beneath the screen; and I provide each of the
said compartments with a valve by means of which the currents of air from the
several apertures in the said compartments are regulated and graduated, as herein-
after explained. I also provide bonnets or hoods over the said apertures for
preventing the middlings or flour when passing to the conveyor from escaping into
the said compartments, these hoods also directing the currents of air. I mount the
feed-trough in connection with the screen in such a manner that a rocking or
pendulum movement is imparted to it for a purpose which will be hereinafter
explained. The said screen projects through the frame of the machine at the ends
thereof, and is provided at one end, centrally of its width, with a box or L-shaped
stand, faced with leather and against which a cam in the form of an equilateral
triangle strikes in its revolutions. The edges of this box are turned up to form a
receptacle for oil to lubricate the cam. The said cam is preferably made with
curved faces or edges and is mounted upon a shaft having its bearings in the frame
of the machine on a line with the centre of the said box. Upon the outside of, and
on a line with the end piece of the screen, and at the same end as the cam-shaft

page_text: there is a bar which is supported by bolts secured to the said frame and having
threads cut upon their outer ends, the said bar being placed between two nuts upon
each of said bolts, thus providing for the adjustment of springs hereinafter described
to or from the frame and for regulating the extent of throw of the screen which is
suspended by means of hangers placed at an angle so that in the to and fro move-
ment of the screen a degree of vibration is imparted to it greatly facilitating the
efficient working of the machine. Flat steel springs secured upon the outer frame
hold the screen against the said bar, excepting when it is forced away by the afore-
said cam moving in the box: when the said cam releases the screen the springs
force it back and by pressing it against the said bar a vibratory percussive move-
ment is imparted to the said screen. The said springs are furnished with set-screws
to alter the tension and regulate the throw of the shaker-frame. Upon the opposite
end of the machine and just above the projecting end of the screen I mount a feed-
trough which is suspended by pivoted links. This trough is also connected to the
screen by arms or links, one at each end, and which, as the screen is vibrated back
and forth by the said cam, also cause said trough to be vibrated or swung on the
link pivots, giving to it a rocking or pendulum motion and distributing the
middlings evenly upon the end of the screen. The frame of the machine is extended
down and around cant-boards or inclines upon or over which that portion of the
middlings falling thereon is conducted to conveyors, the frame forming in connection
with the said inclines, triangular air compartments or boxes herein before referred
to, through which air is conducted from fans employed to create the blast. These
fans are preferably arranged one at the end of each compartment, but if preferred,
one fan of sufficient size to supply both compartments may be used, and connected
with them by means of pipes, one upon each side of the said fan. The aforesaid
cant-boards or inclines are provided with apertures, as herein before mentioned,
through which the air is discharged into the machine to act on the flour or middlings,
and each aperture is provided with a hood or cover above and extending around
the sides for the purposes above named. Each of the said apertures is mado smaller
than the one preceding it, the smallest one being that nearest the foot or tail end
of the machine, and these apertures are so placed that those in one compartment
are not exactly opposite those in the other compartiment, that is to say, cach aper-
ture in one compartment faces the intervening space between each aperture in the
opposite compartment. This arrangement ensures a more equal distribution of the
blast as it enters through these apertures; I provide a bar, preferably lozenge shaped,
in transverse section, which bar is placed longitudinally in the centre of the air-space
below the screen and opposite the aforesaid apertures. This bar serves to break or
chop the wind, thereby preventing eddies or currents which would otherwise be
created under the screen. The aforesaid slide or valve used to regulate and graduate
the blast discharged through the said openings is so arranged that in whatever
position it may be the two apertures nearest the head of the machine in each com-
partment will be always open and the others may be opened more or less as desired.
The raising or lowering of these slides or valves admits more or less blast at either
end of the space below the screen. The said slides or valves may be controlled by
means of arms projecting through the frame, or may be fastened up inside the
frame of the machine, and by raising the valves they are made to only close a por-
tion of each opening, and each succeeding opening in the direction of the tail end
of the machine is closed a little more than the last preceding one. Conveyers are
provided at the lower part of the machine for removing the purified middlings out
of the same and for carrying back the middlings called returns which are to pass
through the machine again or to go to other machines.
Over the screen and at about the centro of the machine a knocker or hammer is
placed (or more than one may be used) which is caused to strike the screen at
regular intervals for the purpose of keeping the cloth clean. The said hammer is
attached to a spring bar and is operated by a cam so formed that immediately the
hammer has delivered its blow it rises instantaneously. This gives to the screen
more freedom and elasticity than would be the case were the hammer to dwell at all

page_text: after striking. The mechanism for this purpose is constructed as follows, that is to
say:-
Upon this screen-frame or across the bolting-cloth is secured a longitudinal strip
against which the said hammer or hammers strike. A bar is fastened to one of the
upper cross bars of the frame (and near the tail end of the machine), and about
midway of the length of this bar is secured the spring-bar, to the end of which the
hammer is connected. This bar extends a short distance beyond the hammer and
rests upon a cam which is supported upon a shaft mounted in the frame and operated
by means of a pulley connected to one end of the shaft, the revolution of which
causes the cam to raise the said spring-bar while said cam rides on its curved face,
but when it reaches its straight face the spring is free to drop instantaneously, and
the tension of the spring-bar throws the hammer against the aforesaid strip, which
jars the screen and clears the meshes of the cloth. I may also provide another
hammer arranged to operate as follows, that is to say:-To the head of the machine,
and about on a line with the centre of the first named hammer, is pivoted an arm
which is also pivoted to the said first named hammer. This arın extends forward
so that its end shall be about on a line with the end of the aforesaid spring-bar,
and has connected to it the said second hammer which by its connection with the
first named hammer through the said arm is also caused to strike the said longitudinal
strip at the same time as the first named hammer, thus jarring the screen at both
ends simultaneously.
The tension of the spring, and the consequent force of the blow given by the
hammers, are regulated by the adjustment of a screw through which the spring is
connected to the bar to which the spring bar is connected.
At the foot or tail end of the machine I provide two cross valves, one of which
is designed to regulate the quantity of meal to be returned to the feeder of the same
machine in order to pass through again or to other machines, and the other valve is
designed to regulate how much of the sifted material should be drawn off as too
poor to be returned for further purification.
Underneath the screen at the foot or tail end of the machine there is a space
between the screen and the frame. This space is covered with cloth through which
some wind escapes, but no meal.
I provide a dust chamber at the top of the machine, and the whole of the upper
part of the latter is open to this chamber which is provided with an aperture at one
end or on one side so that the air may have free exit. The said dust chamber may
if desirable be extended either at the ends or sides of the machine, or both.
In the ordinary construction of screen-frames the cloth is fastened to the frame,
the cloth adjoining the sides and ends of the frame becomes immovable, and there
is no possibility of vibrating the cloth unless imparted through the screen-frame,
such vibration being imperfect. from the fact that the screen is usually suspended
by close-fitting hangers. If tappers or hammers are used in these machines a very
heavy blow must be given to produce a vibration which involves waste of power
and is often detrimental to the working of the screen. I therefore construct a
screen as follows, that is to say:-I make the frame in the ordinary manner and
insert or place springs on the top of the said frame, and I rest sectional screens
upon the said springs. I prefer to employ hollow pieces of india-rubber for the springs,
or the said springs may be made of metal or other suitable material. Longitudinal
strips are fastened on top of the sectional screen and secured to the screen-frame at
either end, and the screens and longitudinal strips are prevented from moving
sidewise, or moving too much vertically, by the use of clamps fastened to the
screen-frame and projecting upward and bent down over the longitudinal strips.
The longitudinal strips and the screens may be further secured by transverse strips
above, or sectional screens may be clamped or bolted together.
In percussion-machines where knockers or hammers are used an even vibration is
given the whole width and length of the screen. The clamps hold the sectional screens
down upon the springs. The sectional screens are provided with tension rods or
bolts placed under the cloth to be out of the way of the flow of the material

page_text: extending across the screen, with nuts at each end for the purpose of tightening the
cloth or covering of the screen. The screen may be provided with curtains of cloth
or other light flexible material extending below the screen and fastened to the
cross-pieces of the screen-frame. The object of the curtains is to prevent.a current
of air from travelling under the whole length of the shaker, and at the same time
to be of such lightness as not practically to interfere with the motion of the
screen.
The machine being set in motion, the middlings are fed through a spout into the
feeder and are evenly distributed on the screen. The arrangement of hangers and
percussion movement produced by the cam and screens striking against the outer
bar cause the middlings to travel rapidly and sift through, also to precipitate the
heavy portions to the bottom, leaving the light bran and fibre on top to be removed
by the action of the screen and blast. The wind as it enters into the compartment
at the openings enters transversely, producing many times the pressure under the
cloth that there is above, also a greater pressure at the head than at the tail of the
machine. The pressure under the cloth prevents the fibre from passing through,
yet there is not enough wind passing through to carry off the fine middlings into
the dust room.
The middlings as they sift through are carried back by one of the
conveyors to the head of the machine and discharged. A valve herein before
mentioned regulates the quantity to be returned, which is also carried to the head
by a conveyor and discharged at an opening. Another valve herein before described
regulates the quantity to be thrown off that is too poor for returns, and by drawing
a slide it will escape, but if the slide is not removed it will go back with the
returns.
Longitudinal strips are provided and fastened at the top sides of machine, to
which strips some light cloth or other suitable material is attached. This material
hangs down till it touches or rests upon the said sectional screens, and thus prevents
the dust from falling below the screen at the sides.

page_text: middlings, and consists in various details of construction hereinafter described,
whereby much better results are obtained than have been attainable with machines
heretofore constructed for this purpose.
The said Invention is illustrated in the accompanying Drawings in which,-
Figure 1 is a side elevation of a machine constructed according to this Invention,
and
Figure 2 is an end elevation of the same.
Figure 3 is a longitudinal section of the said machine, and
Figure 4 is a transverse section of the same on the line x, x, Figure 1.
Like letters indicate the same parts throughout the Drawing.
a represents the main frame of the machine; b is the screen; c is the compart-
ment into which the middlings passing through the screen c fall, and d, d, are fans
employed for forcing air into the wind compartments; e, f, g, are the conveyors.
The remaining parts are hereinafter described.
In carrying the said Invention into practice I form the wind-compartments e, e,
near the bottom of the machine. The cant boards or inclines e¹, e', which con-
stitute one side of these compartments are provided with apertures e along their
sides, through which apertures the blast enters the chamber or compartment c
beneath the screen b. The frame of the said machine is extended down and around
the said cant-boards or inclines e¹, upon or over which that portion of the middlings
which passes through the aforesaid screen is conducted to the conveyor f; the said
frame forms in connection with the said inclines the aforesaid triangular air or
wind compartments or boxes e through which air is forced by the fans d employed
to create the blast. These fans are preferably arranged one at the end of each
compartment, an opening c*, Figure 3, being formed in the end of each of the said
compartments and communicating with the fan-chambers, but if preferred one fan
of sufficient size to supply both compartments may be used, and connected with
them by means of pipes one upon cach side of the said fan. The aforesaid cant
boards or inclines e' are provided with apertures as hereinbefore specified, through
which the air is blown into the machine to act on the flour or middlings. The said
apertures may vary in size, that is to say, each succeeding aperture may be made
smaller than the one preceding it, the smallest one being that nearest the foot or
tail end of the machine, and these apertures are so placed that those in one com-
partment are not exactly opposite or facing those in the other compartment, that is
to say, the apertures in one compartment face the intervening spaces between the
apertures in the opposite compartiment. This arrangement ensures a more equal
distribution of the blast as it enters through these apertures. I provide each of
the said compartments with a slide or valve c³, which preferably consists of a piece
of wood extending longitudinally throughout the length of the apertures ef. By
means of this slide the currents of air passing through the several apertures in the
said compartments may be regulated and graduated as hereinafter explained;
I provide the said apertures with a series of bonnets, hoods, or covers et extending
over and around the sides of the same, for preventing the middlings or flour when

page_text: falling into the compartment c to the conveyor from passing through the said
apertures into the said wind-compartments; these hoods also direct the currents of
air. The aforesaid slide or valve used to regulate and graduate the blast dis-
charged through the openings e³ is so arranged, that in whatever position it may
be, the two apertures nearest the head of the machine in each compartment will be
always open or nearly so, and the others may be opened more or less as desired.
By raising or lowering these slides or valves, more or less of the blast may be
admitted at either end of the compartment c below the screen as desired. The said
Blides or valves may be controlled by means of arms projecting through the frame,
or may be fastened up inside the frame of the machine; by raising the said valves
they are made to only closo a portion of each opening, and each succeeding opening
in the direction of the tail end of the machine is closed slightly more than the last
preceding one.
Within the aforesaid compartment c I arrange a bar c*, which is preferably
lozenge-shaped in transverse section, as shewn in Figure 4, and which is placed
longitudinally in the centro of the air-space below the screen and opposite the
aforesaid apertures. This bar serves to break or chop the wind, thereby preventing
eddies or currents which would otherwise be created under the screen, and effecting
a more equal distribution of the wind; h represents the feed trough through which
the material is fed to the screen b, and which is arranged in such a manner that a
rocking or pendulum movement is imparted to it for a purpose hereinafter
explained; h¹ represents the feed spout arranged in the proper relative position
with regard to the feed trough has shown.
Within this feed spout I arrange a valve consisting of a piece of thin sheet metal
h², see Figure 2a, which is divided or cut through for a portion of its depth, so that
either of the parts h³, ht, may be turned over into any desired position to ensure
the proper distribution of the feed, no matter in what direction the middlings are
fed into the said feed spout.
At the lower end of the feed trough and just above the screen I arrange a
plate of zinc or other suitable material, which is provided with a series of small
holes. The middlings as they are fed into the said feed trough from the feed spout
fall upon this plate, and are evenly dispersed over the said perforated plate, and
are caused to pass through the openings in the latter evenly over the screen, while
the same moves to and fro as hereinafter described. The said screen projects
through the frame of the machine at the ends thereof, and is movable endwise in
one direction by means of a cam arranged to act upon the said screen three
times during each revolution of the shaft i, the portion of tho said screen upon
which the said cam acts being preferably faced with leather or other suitable
material. The said cam is preferably made with curved faces or edges, as shown
in Figure 3, and is mounted upon a shaft i which has its bearings in the main
frame of the machine. Upon the outside of and in a line with the end piece of
the screen, and at the same end as the cam shaft i I arrango a bar j, which is
supported by screwed bolts ; secured to the main frame; the said bar being
held in any desired position upon these bolts by nuts, or by other suitable means,
thus permitting the extent of movement or throw of the screen b to be regulated
as desired. The said screen is suspended by hangers 6 placed at an angle as
shewn, so that in the to and fro movement of the screen a degree of vibration is
imparted to it, greatly facilitating the efficient working of the machine. Flat steel
springs & secured upon the outer framo of the machine hold the screen against the
aforesaid bar j, excepting when it is acted upon by the cam i; when one of the pro-
jecting parts of the said cam releases the said screen, the springs k effect the return
movement thereof, and by forcing it against tho said bar a vibratory percussive
inovement is imparted to the said screen. The said springs are secured to the main
frame by set screws ', and by means of these screws the tension of the said springs
may be altered to regulate the throw of the screen or shaker frame. The cloth
covering the said screen is graduated, that is to say, the cloth is of fine texture at

page_text: the head of the machine, and becomes coarser towards the tail end, thereby grading
The different grades
the middlings as they pass through into the compartment c.
may if desired be drawn off from the lower part of the said chamber when desired
by means of suitable slides or valves in connection with openings in the chamber.
Upon the opposite end of the machine and just above the projecting end of the
screen I mount the feed trough. This trough is connected to the said screen, and
as the latter is moved to and fro by the said cam the trough will also have given to
it a reciprocating motion, which ensures the even distribution of the middlings
upon the end of the said screen.
The conveyor f in the lower part of the compartment c serves to carry the
purified middlings as they sift through the screen to the opening f' at the head or
front of the machine, from which opening the said purified middlings are conducted
by a chute, or otherwise discharged into any suitable receptacle. The conveyor y
serves when desired to carry back the portions of the middlings called returns,
which are to be passed through the machine again, or are to be taken to other
machines; the said returns being carried along by the conveyor g to the outlet g*.
One or more suitable valves g¹³, 9%, may be arranged between the lower part of the
compartment c and the compartment containing the conveyor g. The valve or
valves g are designed to regulate the quantity of meal to be returned to the feeder
of the same machine to pass therethrough a second time or to another machine;
the other valve g³ is designed to regulate the withdrawal or removal of the sifted
material which is too poor to be returned for further purification.
Over the screen, and at about the centro of the machine, I in some cases provido
a knocker or hammer, or two or more of the same, the said hammer or hammers
being caused to strike the screen at regular intervals for the purpose of keeping the
cloth clean. The said hammer is attached to a spring-bar, and is operated by a
cam so formed that the hammer after delivering its blow rises instantaneously.
This arrangement gives to the screen more freedom and elasticity than would be
the case were the hammer to "dwell or pause after striking. The mechanism for
this purpose is constructed as follows, that is to say :-
"
Upon the screen-frame or across the bolting cloth is secured a longitudinal strip,
A bar is fastened to one
against which the said hammer or hammers will strike.
of the upper cross bars of the frame, and near the tail end of the machine, and
about midway of the length of this bar is secured the spring bar, to the end of
which the hammer is connected. This bar extends a short distance beyond the
hammer, and rests upon a cam which is supported upon a shaft mounted in the.
frame, and operated by means of a pulley connected to one end of the shaft; the
revolution of this shaft causes the cam to raise the spring-bar, while the said cam
rides on its curved face, but when it reaches its straight face the spring is free to
drop instantaneously, and the tension of the spring-bar throws the hammer against
the aforesaid strip, which jars the screen and clears the meshes of the cloth. I may
:-To
also provide another hammer arranged to operate as follows, that is to say :-
the head of the machine, and about on a line with the centre of the first
named hammer is pivoted an arm, which is also pivoted to the said first named
hammer.
This arm extends forward, so that its end will be about on a line with the end
of the aforesaid spring-bar, and has connected to it the said second hammer, which
by its connection with the first named hammer through the said arm is also caused
to strike the said longitudinal strip at the same time as the first named hammer
thus jarring the screen at both ends simultaneously.
The tension of the spring, and the consequent force of the blow given bythe
hammers are regulated by the adjustment of a screw, through which the spring is
connected to the aforesaid bar.
I prefer in some cases, however, to employ a brush as shewn at 7 instead of the
aforesaid hammer or hammers, the said brush being arranged and operated as
follows, that is to say:-At the front and tail ends of the said machine I arrange
>

page_text: shafts m, n; the shaft n at the tail end receives motion from the shaft i through
the gear wheels 1, 2, 3, and 4, suitable clutch mechanism being arranged in con-
nection with the pulley 4, so that the rotation of the said shaft n may be stopped
or started, as desired.
Upon the said shafts I arrange sprocket or chain wheels m', n¹, around which n
chain o passes, as shown in Figure 3. Upon this chain the brush l, which extends
across the entire width of the cloth, is fixed in such a manner that by and during
the movement of the chain the said brush will be carried along by the same, and
will come in contact with the cloth of the screen at the front of the machine, and
leave the same at the tail end, and will then travel over the wheel n' back to the
front end without touching the screen; p represents a sprocket wheel, which is
placed at or near the centre of the machine, and which serves as a support for the
chain between the wheels m¹, n¹.
Instead of employing a brush attached to a chain and continually revolving with
the same, I may in some cases employ an automatic brush attachment which is
driven by suitable gearing in such a manner that the said brush will make one
movement over the cloth, and will then remain stationary for any desired time
before again being set in motion.
At the tail of the machine within the compartment c I arrange two cross valves
q, q', which may be adjusted upon their hinges q*, q*, as desired by means of rods
or bars q², q³, extending through the rear end of the machine. The valvo q
regulates the quantity of middlings to be returned to the machine or to other
machines, the said middlings being carried along to the outlet g* by the conveyor g,
as above described. The valve q' regulates the quantity of middlings to be drawn
off, that is to say, the middlings which are too poor for returns. By drawing out
the slides g², g**, it will escape, but if the said slides are not drawn out it will be
carried back with the returns.
Underneath the screen at the foot or tail end of the machine there is a space
between the screen and the frame. This space is covered with cloth c through
which air can escape, but which will prevent the passage of meal.
In connection with the machine as above described and at the top of the same,
I employ a dust chamber (not shewn) of any suitable construction; the whole of
the upper part of the said machine is open to this dust chamber, which is provided
with an aperture at one end or on one side so that the air may have free exit.
The said dust chamber may if desirable be extended either at the ends or sides of
the machine, or in both directions.
In the ordinary construction of screen-frames the cloth is fastened to the frame;
the cloth adjoining the sides and ends of the frame becomes immovable, and thero
is no possibility of imparting vibration to the cloth except through the screen-frame,
such vibration being insufficient for the reason that the screen is usually suspended
by close fitting hangers. If tappers or hammers are used in these machines a very
heavy blow must be given to produce vibration, which involves waste of power and
is often detrimental to the working of the screen. I therefore in some cases
construct a screen as follows, that is to say:-I make the frame in the ordinary
manner, and insert or place on the top of the said frame springs, whercon I support
sectional screens. I prefer to form the said springs of hollow pieces of india rubber,
but they may be made of metal or other suitable material. Longitudinal strips are
fastened on the top of the sectional screen, and secured to the screen-frame at either
end and to the screens. These longitudinal strips are kept from moving sidewise, or
moving too far vertically, by clamps fastened to the screen frame and projecting
upward and bent down over the longitudinal strips. The said longitudinal strips
and the screens may be further secured by transverse strips above, or the sectional
screens may be clamped or bolted together.
In percussion-machines where knockers or hammers are used, an even vibration
is given to the screen throughout its entire width and length. The clamps hold
the sectional screens down upon the springs. The sectional screens are provided

page_text: with tension rods or bolts placed under the cloth clear or out of the way of the
Bow of the material; the said rods extend across the screen, and are provided with
set screws or nuts at each end for the purpose of tightening the cloth or covering of
the screen.
The screen may be provided with curtains of cloth or other light
flexible material extending above the screen and fastened to the upper sides of the
screen frame. The object of the curtains is to prevent the falling back of any
impurities from the dust room into the wind chamber.
The said curtains are formed of light material which will not interfere with the
motion of the screen.
The operation of the said machine is as follows:-The machine being set in
motion the middlings are fed through a spout into the feeder or feed trough h, and
are evenly distributed on the screen b. The arrangement of the hangers b*, and
the percussive movement produced by the cam i, and the striking of the screen
against the outer bar j cause the middlings to travel rapidly and to be sifted
through the cloth of the screen into the compartment c, the heavy particles being
precipitated to the bottom, leaving on the top the light bran and fibre, to be removed
by the action of the screen and blast. The wind as it enters the compartment c
through the openings e in a transverse direction, produces under the cloth a
pressure greatly exceeding that which exists above the same, and also a greater
pressure at the head than at the tail of the machine. This pressure under the
cloth prevents the passing of the fibre through it, but there will not be sufficient
wind forced up or passing through the cloth to carry off the fine middlings into the
dust room. The middlings as they sift through the screen are carried back by the
conveyor f to the head of the machine, and discharged through the opening f*; or
a portion of such middlings will be allowed to pass into the conveyor to be
carried by the same to the opening g* and returned to the same machine, or taken
to another machine.
Having thus fully described the said Invention as cominunicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim in a machine for purifying flour and middlings,-
First. The wind compartment or compartments lying parallel with the conveyor
and arranged to conduct the air from a fan or blower, and discharge the same into
the body of the machine through a series of lateral openings in combination with
which is an adjustable valve, whereby the said openings may be graduated or
increased and diminished, substantially as and for the purpose specified.
Second. The wind compartment with its inner side formed by the cant-board
provided with the aforesaid lateral openings in combination with the overhanging
bonnets or hoods, and with a valve or valves, all substantially as and for the
purposes specified.
Third. The feed-trough, arranged substantially as shewn and described, and
operating as and for the purposes specified.
Fourth. The perforated plate arranged within the feed-trough to distribute the
middlings evenly or uniformly across the surface of the end of the screen, sub-
stantially as set forth.
Fifth. The plate or valve placed within the feed-spout and so constructed that it
may be bent or inclined to direct the middlings to either side of the feed-trough to
ensure the equal distribution or division of the same, substantially as and for the
purpose specified.
Sixth. The rotary brush arranged in combination with the other parts of the
machine, as shewn and operating, as and for the purpose specified.
Seventh. The apertures in the two wind-chambers arranged in such a manner,
that those of one chamber will be opposite the spaces between the apertures in the
other chamber, substantiallly as and for the purposes specified.
Eighth. The novel devices specified in the foregoing claiming clauses or any
mere inodification thereof, in combination with the other parts of the machine

page_text: shewn in the Drawings, or a substantially similar machine as and for the purposes
specified.
In witness whereof, I tho said Moses Lyon, have hereunto set my hand and
scal, this Eleventh day of July, in the year of our Lord One thousand eight
hundred and seventy nine.
M. LYON. (L.S.)