IMPROVEMENTS IN MACHINERY OR APPARATUS FOR WORKING OR CUTTING COAL OR MINERALS. AND FOR COMPRESSING OR EXHAUSTING AIR TO BE EMPLOYED THEREIN, OR FOR OTHER PURPOSES. SOME PARTS OF WHICH APPARATUS ARE ALSO APPLICABLE TO UPRIGHT SHAFTS AND OTHER PARTS FOR REGULATING THE FLOW OR DISCHARGE OF STEAM OR OTHER ELASTIC FLUIDS
Year: 1865

page_text: LETTERS PATENT to William Leatham, of Brookfield Works, Leeds, in
the County of York, Engineer, for the Invention of "IMPROVEMENTS
IN MACHINERY OR APPARATUS FOR WORKING OR CUTTING COAL OR MINERALS.
AND FOR COMPRESSING OR EXHAUSTING AIR TO BE EMPLOYED THEREIN, OR FOR
OTHER PURPOSES. SOME PARTS OF WHICH APPARATUS ARE ALSO APPLICABLE TO
UPRIGHT SHAFTS AND OTHER PARTS FOR REGULATING THE FLOW OR DISCHARGE
OF STEAM OR OTHER ELASTIC FLUIDS."
Sealed the 27th October 1865, and dated the 29th April 1865.
PROVISIONAL SPECIFICATION left by the said William Leatham at the
Office of the Commissioners of Patents, with his P'etition, on the 29th
April 1865.
I, WILLIAM LEATHAM, of Brookfield Works, Leeds, in the County of York,
Engineer,do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN MACHINERY OR APPARATUS FOR WORKING OR CUTTING COAL OR MINERALS, AND
FOR COMPRESSING OR EXHAUSTING AIR TO BE EMPLOYED THEREIN. OR FOR OTHER
PURPOSES. SOME PARTS OF WHICH APPARATUS ARE ALSO APPLICABLE TO UPRIGHT
SHAFTS AND OTHER PARTS FOR REGULATING THE FLOW OR DISCHARGE OF STEAM OR
OTHER ELASTIC FLUIDS," to be as follows:-
The first part of this Invention relates to machinery for working or cutting
grooves in coal or minerals in mines, quarries, and other places by means of
picks or other cutting instruments actuated by the force of compressed atmo-
cylinder
spheric air or other motive power acting on a piston or pistons in a
or cylinders.
The improvements consist, firstly, in the application to such machinery of
Price Sd.]

page_text: one, two, or more anchors capable of hxing or holding themselves in the
groove or grooves cut in the coal or minerals, so as to hold the machine firm
during its action,such anchors being rendered self-acting by the action of the
machine in being fixed during each stroke of the pick or at the time the cut
is being made, and loose whilst the machine is being moved forward. The
anchors may be constructed of one, two, or more shafts mounted in bearings
on the machine and extending into the groove, and having a series of tongues
or projections thereon, which are pointed or sharpened, so that by turning
the shafts on their axis into one position the points will penetrate and fix
themselves in the coal or mineral on each side of the groove, but when the
shaftsare turned into another position the said projections and shafts will be
free to move
in the groove. Or instead of shafts to turn on their axes
such projections may be attached to rods, bars, or plates extending into the
groove, and capable of being expanded by lever or wedge motion operated by
cam or tappet on a shaft of the machine, or by compressed air or other
motive power caused to act thereon by piston and cylinder. One or more of
such anchors may be used as cutters at the back or far end of the groove to
relieve or prepare the block of coal before the "wedging," or the adoption of
other means which may be used to force the said block of coal or ninerals
out from its bed.
Secondly, these improvements consistina peculiar construction and method
of fixing the picks. The fixing end of the pick is made open like a fork to
receive a wedge of an angular shape corresponding with a hole in un eccentric
box formed on the crank shaft. On and near the bottom of the said upright
shaft or spindle I form a part of a collar or flange to work in a groove to give
strength to and be a means to keep the said shaft in its proper position. The
arm of the pick is made of an elbow shape and jointed to allow the point
of the pick to move inward or give way to allow forward movement of the
machine. A tension bar with a slot in it is applied to give strength to the
pick and to allow the required inward movement of the point of the pick, and
a spring is applied to the bar to press the point outward when cutting. The
nose or point of the pick is made portable, and formed with a wedge-shaped
socket to fit on the arm of the pick, so as to be readily taken off to be
sharpened and another put on. The arm of the pick is also provided with a
feather or another arm, which enters the groove when in action and receives
part of the cuttings, which by the return or backward stroke clears the road
for the anchors.
Thirdly, in the application of an additional cylinder forming compound
cylinders and valves, which cylinders and valves are on the oscillating prin-

page_text: ciple, and are so connected with joint levers and rods that one piston will
make two strokes while the other piston is making one stroke, and while the
main cylinder piston makes one stroke the pick will strike twice, and will
commence to give the blow at or about the centre of the stroke when the
velocity of the piston is the greatest, causing the pick to strike suddenly.
This additional cylinder is so arranged as to compress air, and thereby form a
retarding action on the main cylinder piston in the back stroke of the pick,
giving more time for the other actions to take place in the movement of the
machine. It is supplied with slides and connecting rod as a compensating
motion for curves described by the radiating arms or cranks. It is also
furnished with an extra valve and operated so that the full force of its power
can be applied throughout the stroke, making the machine of double power
in cutting, whilst its action is retarded in the back stroke when other motions
are taking place.
Fourthly, the improvements consist of means of constructing the frame or
carriage to rise or fall to suit or accommodate the pick the height where
the groove is to be cut in the coal or other minerals. The said frame is made
to rise and lower in slides by means of screws, levers, or inclined planes, or
other equivalent means, and a socond frame forms the foundation for the
fixing of the cylinders, brackets, and other supports of the working parts.
Fifthly, in constructing the flange of one or more of the wheels with
ratchet teeth to be acted upon by levers, catches, or pawls. The machine
when moved forward is sustained or held in position by other catches taking
in the said teeth. The rim of the wheel or wheels is perforated to fit ou
conical pins formed on the rails, thus causing a deadlock to the machine
during the cutting process, and the rails are connected to corrugated iron
plates, which form a portable frame of convenient length, thus forming ties
and sleepers to the rails. This machine when not moving by self-acting means
may be moved by hand.
Sixthly, the improvements consist in the application to the carriage of a
lever, at one end of which is formed a seat for the attendant to sit upon
during the working of the machine, and at or near the other is a rod con-
nected to an anchor having prongs, so as to make an indentation in the roof
or top of the mine, by the use of which stability is given to the machine'
during the cutting process, and before the machine is moved forward on the
rails a cam is caused to act upon the lever, so as to relieve the pressure
against the top when the machine is at liberty to move forward to make
another cut. In some mines, quarries, or other places I may find it con-
venient for the machine to lay down its own rails or tramway, for which

page_text: purpose I apply levers to the carriage to act on the rails to move them forward
at the time when the anchors are fixed in the grooves (the rails and their
framing in such case being mounted on wheels) the rails and the carriage
being moved forward alternately by intermittent motions.
The second part of this Invention relates to machinery or apparatus for
compressing or exhausting atmospheric air to be employed in working coal-
cutting machines or for other purposes, and the improvements consist in a
cylindrical vessel placed with its axis in a vertical position, which is employed
as a receiver or air reservoir having suitable inlet and outlet valves. To the
top of this vessel are arranged in a radial line one, two, three, or more pairs
of air pumps, the plungers of each pair being connected by a beam or lever
hinged on an intermediate fulcrum or bearing, so that as one plunger is
lowered the other will be raised. A circular plate is fixed on the end of a
spindle mounted vertically and centrally upon the vessel, and cogs are formed
thereon, by which rotary motion may be communicated to the said plate by
means of pinion and shaft from any convenient source of power. A number
of cams or tappets corresponding to the number of pairs of pumps are formed
on or attached to the under side of the plate in a radial line corresponding to.
the centres of the plungers of the pumps, and in the end of each plunger is a
friction roller for the cams to act upon. Friction rollers are placed above the
plate to prevent its lifting when in action, and also under a plate fixed below
to relieve the pressure on the footstep. These friction rollers may be applied
to upright shafts of mill and other gearing for the saine purpose. The
plungers have india-rubber or other elastic packings so arranged that the
greater the pressure is on the plunger the tighter becomes the packing. I
employ a diminishing valve of a peculiar construction for regulating the flow
or discharge of the compound air, or for supply thereof to the cylinders of
the machine or engine; which valve is also applicable for regulating the flow
or discharge or supply of steam or other clastic fluids.. It consists of a casing
or box, with a branch over the top part furnished with an ordinary safety valve
and lever, and an outlet pipe. Within this branch is fixed a short perforated
cylinder and a piston, the rod of which is connected to a compressible vessel,
or two flexible dished plates joined at their edges, but held asunder by springs
in the middle. This vessel is connected to the casing by a tube passing
through the bottom part, to which is applied an ordinary stuffing box. A
spindle passes loosely through this tube to the interior of the flexible vessel,
which by means of right and left hand screw threads thereon the pressure of
the springs may be adjusted in the interior of the compressible vessel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Leatham in the Great Seal Patent Office on the
28th October 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
LEATHAM, of Brookfield Works, Leeds, in the County of York, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of April, 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 William Leatham, Her special licence that I, the said William
Leatham, my executors, administrators, and assigns, or such others as I
the said William Leatham, 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 "IMPROVE.
MENTS IN MACHINERY OR APPARATUS FOR WORKING OR CUTTING C (#1 OR MINERALS,
AND FOR COMPRESSING OR EXHAUSTING AIR TO BE EMPLOYED THEREIN, OR FOR
OTHER PURPOSES, SOME PARTS OF WHICH APPARATUS ARE ALSO APPLICABLE TO
UPRIGHT SHAFTS AND OTHER PARTS FOR REGULATING THE FLOW OR DISCHARGE OF
STEAM OR OTHER ELASTIC FLUIDS" upon the condition (amongst others) that
I, the said William Leatham, my executors or administrators, by an instru-
ment 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 William Leatham, 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 fol-
lowing statement, and accompanying two Sheets of Drawings (that is to
say):
;
The first part of this Invention relates to machinery for woking or cutting
grooves in coal or minerals in mines, quarries, and other places by means of
picks or other cutting instruments actuated by the force of compressed atmo-
spheric air or other motive power acting on a piston or pistons in a cylinder
or cylinders.

page_text: The improvements consist, firstly, in the application to such machinery of
one, two, or more anchors capable to fix and hold themselves in the groove or
grooves cut in the coal or minerals, so as hold the machine firm during its
action, such anchors being rendered self-acting by the action of the machine
in being fixed during each stroke of the pick, or at the time the cut is being
made, and loose whilst the machine is being moved forward. These anchors
may be constructed of one, two, or more shafts mounted in bearings on the
machine, and extending into the grooves, and having a series of tongues or
projections thereon, which are pointed or sharpened, so that by turning the
shafts on their axis into one position the points will penitrate and fix them-
selves in the coal or minerals on each side of the groove; but when the shafts
are turned into another position the said projections and shafts will be free to
move in the groove. Or instead of shafts to turn on their axis, such pro-
jections may be attached to rods, bars, or plates extending into the groove,
and capable of being expanded by lever or wedge motion operated by cam or
tappet on a shaft of the machine, or by compressed air or other motive power
caused to act thereon by piston and cylinder. One or more of such anchors
may be used as cutters at the back or far end of the groove to relieve of
prepare the block of coal before the "wedging" or the adoption of other
means which may be used to force the said block of coal or minerals out from
its bed.
A.
Secondly, these improvements consist in a peculiar construction and method
of fixing the picks. The fixing end of the pick is made open like a fork to
receive a wedge of an angular shape corresponding with a hole in an eccentric
box formed on the crank shaft. On and near the bottom of the said upright
shaft or spindle I form a collar or flange to work in a groove to give strength
to and be a means to keep the said shaft in its proper position. The arm of
the pick is made of an elbow shape, and jointed to allow the point of the pick
to move inward or give way to allow forward movement of the machine.
teusion bar, with a slot in, is applied to give strength to the pick and to allow
the required inward movement of the point of the pick, and a spring is applied
to the bar to press the point outward when cutting. The nose or point of the
pick is made portable, and formed with a wedge-shaped socket to fit on the
arm of the pick, so as to be readily taken off to be sharpened and another put
The arm of the pick is also provided with a feather or another arm,
which enters the groove when in action and receives part of the cuttings,
which by the return or backward stroke clears the road for the anchors.
Thirdly, in the application of an addition al cylinder forming compound
cylinders and valves, are our the oscillating principle, and are so connected
on.

page_text: with joints, levers, and rods that one piston will make two strokes while
the other piston is making one stroke, and while the main cylinder
piston makes one stroke the pick will strike twice, and will commence
to give the blow at or about the centre of the stroke when the velocity
of the piston is the greatest, causing the pick to strike suddenly. This
additional cylinder is so arranged as to compress air, and thereby firm a
retarding action on the main cylinder piston in the back stroke of the pick,
giving more time for the other actions to take place in the movement of the
machine. It is supplied with slides and connecting rod as a compensating
motion for other curves described by the radiating arms or cranks. It is also
furnished with an extra valve and operated so that the full force of its power
can be applied throughout the stroke, making the machine of double power
in cutting, whilst its action is retarded in the back stroke when other motions
are taking place.
Fourthly, the improvements consist of means of constructing the frame or
carriage to rise or fall to suit or accommodate the pick to the height where
the groove is to be cut in the coal or other minerals. The said frame is made
to rise and lower in slides by means of screws, levers, or inclined planes, or
other equivalent means, and a second frame forms the foundation for the
fixings of the cylinders, brackets, and other supports of the woking parts.
ย
Fifthly, in constructing the flange of one or more of the wheels with ratchet
teeth to be acted upon by levers, catches, or palls. The machine when
moved forward is sustained or held in position by other catches taking into
the said teeth. The rim of the wheel or wheels is perforated to fit ou conical
pins formed on the rails, thus causing a dead lock to the machine during the
cutting process. The rails are constructed of corrugated iron plates, so as to
form a portable frame of convenient length, thus forming ties and sleepers
to the rails. This machine when not moving by self-acting meaus may be
moved by hand.
Sixthly, the improvements consist in the application to the carriage of a
lever, at one end of which is formed a seat for the attendaut to sit upon
during the work of the machine, and at or near the other is a rod connected
to an anchor having prongs, so as to make au indendation in the roof or top
of the mine, by the use of which stability is given to the machine during the
cutting process, and before the machine is moved forward on the rails a cam
is caused to act upon the lever, so as to relieve the pressure against the top
when the machine is at liberty to move forward to make another cut. In
some mines, quarries, or other places I may find it convenient for the
machine to lay down its own rails or tramway; for which purpose I apply

page_text: levers to the carriage to act on the rails to move them forward at the time
when the anchors are fixed in the grooves, the rails in such case being
mounted on wheels,the rails and the carriage being moved forward alternately
by intermittent motions.
The second part of this Invention relates to machinery or apparatus for
compressing or exhausting atmospheric air to be employed in working coal-
cutting machines, or for other purposes, and the improvements consist of a
cylindrical vessel placed with its axis in a vertical position, which is employed
as a receiver or air reservoir, having suitable inlet and outlet valves. To the
top of this vessel are arranged in a radial line one, two, three, or more pairs
of air pumps, the plungers of each pair being connected by a beam or lever
hinged on an intermediate fulcrum or bearing, so that as one plunger is
lowered the other will be raised. A circular plate is fixed on the end of a
spindle mounted vertically and centrally upon the vessel, and cogs are formed
thereon, by which rotary motion may be communicated to the said plate by
means of pinion and shaft from any convenient source of power. A number
of cams or tappets corresponding to the number of pairs of pumps are formed
on or attached to the under side of the plate in a radial line corresponding to
the centres of the plungers of the pumps, and in the end of each plunger is a
friction roller for the cams to act upon. Friction rollers are placed above the
plate to prevent its lifting when in action, and also under the plate to relieve
the pressure on the footstep. These friction rollers may be applied to
upright shafts of mill and other gearing for the same purpose. The plungers
have elastic packings, so arranged that the greater the pressure is the tighter
becomes the packing. I employ a diminishing valve of a peculiar construction
for regulating the flow or discharge of the compressed air, or for supply
thereof to the cylinders of the machine or engine, which valve is also appli-
cable for regulating the discharge or supply of steam or other elastic fluids.
It consists of a casing or box, with a branch over the top part furnished with
an ordinary safety valve and lever, and an outlet pipe. Within this branch is
fixed a short perforated cylinder and a piston, the rod of which is connected to
a compressible vessel, or two flexible dished plates joined at their edges, but
held asunder by springs in the middle. This vessel is connected to the casing
by a tube passing through the bottom part, to which is applied an ordinary
stuffing box. A spindle passes loosely through this tube to the interior of the
flexible vessel, which by means of right and left hand screw threads thereon
the pressure of the springs may be adjusted.

page_text: Fig. 1, Sheet L., is a side elevation of a machine for working or cutting
coal or minerals constructed according to this Invention; Figs. 2 and 3 are
end elevations, and Fig. 4 is a plan of the same.
A, A, are anchors or shafts, with tongues or pointed projections a, a, a,
thereon, which shafts are mounted in bearings of the framework. On each
shaft is fixed a lever B, which are connected by a rod B', and on one of these
shafts is also fixed another lever C, to the top end of which are attached a
pair of spring catches C1 and C2, which are acted upon by a cam D fixed on
the top end of a socket working on an upright spindle D' for operating the
lever C, which is pressed towards the cam by a spring C3, and to this socket
is also affixed a lever D jointed to the piston rod D3, by the action of which
an intermittent rocking motion is given to the anchors for fastening and
loosening them in the groove (as it is cut in the coal or mineral) at each
stroke of the pick, and these anchors may be operated by a hand lever affixed
to the rocking motion if desirable; and one or more of such anchors may be
employed for cutting a groove at the back by having a cutter formed as shewn
at Fig. 5, or the end projection on each of these anchors may be so formed.
E is the pick, which is open like a fork at the fixing end, and a suitable hole
or box E' is formed in the crank shaft. E to receive the pick, and a wedge E³
is fitted in so as to hold it in the box, as shewn at Fig. 6 and 7. The crank
arm E' is connected to the piston rod by a link E, which with the lever D
constitutes a knee joint, by means of which two blows of the pick is effected
at each stroke of the piston. A collar E is formed on the crank shaft
adjoining the pick box, which is recessed into the bearing to give additional
strength thereto, and to keep the said shaft in proper position. The pick is
jointed at e, and a bar or rod E7 is also jointed to the nose of the pick, and is
attached the other end by a pin passing through a slott in the end of said
rod, which end bears against a spring e, which presses the nose outward
whilst the blow is struck, and also gives way for forward movement of
the machine during the back action. Or instead of this spring and slott, an
eccentric, with a swing arm and weight Es, as shewn in Fig. 8, may be
employed, which may be so arranged that by the swing of the pick the
weighted arm is caused to swing and turn the eccentric into the opposite
position, so as to hold the nose of the pick outward during the blow, and then
inward during the back stroke, thus cleaning the point of the pick on its
return action from the cut surface of the coal or mineral; or instead of an
eccentric, the swing arm may operate on a wedge for the same purpose. The

page_text: point of the pick is mad portable, and is fixed with a cotter, as shown in
dotted lines, so as that one nose may be exchanged for another when requiring
to be sharpened, and the point of the pick may be capable of expanding when
the blow is given by means of a wedge, as shewn in Figs. 9 and 10, where the
wedge Z is driven in by coming contact with the face of the coal, and
pushed out by the drawing in of the point. A feather or clearer E is
attached to the pick arm, which clears the groove at each return or back
stroke, thus clearing a roadway for the anchors to follow and fix themselves
therein. G is an additional or auxiliary cylinder, which is fixed upon the
ordinary cylinder, and oscillates therewith; G is the piston rod thereof, which
is connected by a rod G to a lever G³ fixed on the crank shaft E. This
piston strikes with each stroke of the pick and makes two strokes whilst the
ordinary piston makes butone, by reason of the latter being connected to the
two cranks or "knee joint," which causes the pick to strike after passing (in
either direction) the lines of centres, which are shewn by the dotted line H,I
The valves of this auxiliary cylinder are so arranged as to admit of compressed
air, behind the piston or to the back end of the cylinder at the proper time to
assist in giving the blow, and which air is only partially exhausted at the
return of the pick, whereby the piston is retarded in its back stroke by
having to act against and compress the air in that end of the cylinder, and
also by having no admission of air to the other side of the piston, thereby
tending to produce a vacuum in the front end, or the front end of the cylinder
may be opened to the atmosphere. By this application and arrangement
a quick forward stroke of the pick is obtained with a slow backward stroke
or movement, thereby giving time for loosening the anchors, effecting the
forward movement of the machine, and the refixing of the anchors for the
next stroke of the pick. J is the valve rod, in a slot of which is introduced
one arm of a lever J, another arm being inserted into a recess.J' formed in
the cam D, by which the valves are operated. Or the said valves may be
operated by the hand lever J3, the other arm being removed from the recess
J in the cam. K is a guide frame fixed to the auxiliary cylinder for friction
rollers on the end of the piston rod to act against to prevent the cross strain
on the connecting rod. The main framing of the machine, which support
the cylinders and working parts, is mounted in or attached by slides to the
side frames M, which are supported on the running or carrying wheels. This
mair framing is raised or lowered by means of screws N,gear wheels N¹, and
the shaft N, operated by a hand wheel or winch handle N³, so as to set or
ariange the picks to the required positions for cutting the groove in the coal
or mineral. Or instead of screws inclined plains or wedges may be employed

page_text: for this purpose. The flanges of the running wheels are constructed or
formed into ratchet teeth, and catches or pawls Pare hinged on a slidable
bar P", which is operated at the proper time by a suitably formed cam P² on
the socket D to to impell the machine forwards. These catches maybe placed
out of contact with the ratchei. teeth by means of the hand lever P3 to prevent
forward movement of the machine when required. The machine when thus
moved forward is held in that position byother catches P and Puntill the next
forward movement. The rims of the wheels are also perforated so as to fit
on conical pins Pe formed or fixed on the rails S. The rails S are fixed to bed
plates of corrogated iron T of convenient length, forming sleepers and ties
thereto. U is a lever supported on a bearing fixed to the framing of the
machine, see Fig: 13; at one end in a seat U' suspended or attached for the
attendant to sit upon during the working, and at the other end is an anchor
or prongs U projecting upwards to the roof, by which the weight of the
attendant will exert a pressure on the machine during the cutting, and which
weight and pressure will be removed for the movement of the machineby
means of a moveable cam, incline, or wedge V, which is operated by the
piston rod, and passes under the friction roller Vattached to the said lever
by the rod V This wedge is supported on the guide frame W, which also
guides the piston rod G³, and prevents lateral strain from being exerted
thereen by the cross action of the lever G³, the stud by which the connecting
rod is jointed thereto not being placed in the axial line of the said piston rod,
or in the centre of the oscillation. Figs. 11 and 12 are an elevation and plan
of a set of rails and sleepers, with cross ties framed together and mounted on
wheels, by which they are more readily moved forward in the working of a
mine or clswhere. And if found desireable or advantageous such arrange-
ments of rails may be propelled intermittantly by a jointed lever or lever X
hinged to the frame and connected to the socket of the machine, which
lever takes into teeth or pins Y on the wheels Z, when at each forward stroke
of the pick, and whilst the machine is fixed by the anchors the rails may be
pushed forward.
When the rails become stationary the machine is pushed
forward, thus the machine and its rails may be alternately moved forward
along the working of the mine.
The second part of this Invention is illustrated on Sheet II. of the annexed
Drawings, wherein Fig. 1 is a vertical section of a machine constructed
according to my improvements, and Fig. 2 is a plan of the sume.
A is the cylindrical vessel, on the cover A' of which are arranged three
pairs of air pumps B, valves B₁ being provided at the bottom ends of each
barrel opening to the vessel or receiver A, and the bottom of each ram or

page_text: plunger B2 is also provided with a valve B3 opening to the barrel, the tops of
the said plungers being surmounted with friction rollers B, and a short beam
or lever B connects each pair of plungers, resting or having its fulcrum on a
bearing or bracket B6 fixed to the barrel as shown. A circular plate C is
mounted on a vertical spindle, supported and capable of rotating in a socket
or bearing C¹ fixed to the cover of the vessel. On the under side of this plate
are three cams C2, which are so arranged as to come in contact with the
friction rollers of the plungers. A circular cascing D is placed around the
pumps and fixed water-tight upon the cover of the cylindrical vessel, forming
another vessel, which is supplied with water nearly to the top of the pump
barrels to keep the pumps cool when in use, and a series of brackets D' are
bolted to the top of this casing carrying friction rollers De, which rest upon
the circular plate to prevent its being lifted by its action on the plungers, and
also under the plate to relieve the pressure of the footstep. This arrange-
ment of friction rollers may be applied to upright shafts generally to
relieve the pressure of the footstep. A circular rack D is also fixed or
cast on the plate, in the teeth of which a pinion E gears. This pinion is
mounted on a shaft E', which may be supported in suitable bearings and
receive rotary motion from any convenient source of power, so as to
give rotary motion to the circular, the cams on which will act upon the
friction rollers and depress the plungers in rotation, and whilst one of each
pair is being depressed foreing air from the barrels through the valves into
the vessel or receiver, the other plungers will be rising and their valves
opened receiving a fresh supply of air to the barrels ready for the next return
stroke, and so on. A pair of these pumps are shewn in clevation at Fig. 5,
also the edge view of the circular plate with the rack thereon, and the pinion
in gear with it,and one of the cams underneath the plate in contact with the
friction rollers. Fig. 4 is a view of the under side of the plate shewing the
arrangement of the cams. The interior packing rings of the plungers are of
vulcanized india-rubber or other elastic material, and when compressed acts
upon another ring or rings of other material, so that as the pressure in the
vessel becomes greater the rings press or swell outwards against the side of
the barrels and thereby tighten the packing or fit to the plungers, so as
to prevent the escape of air at the sides of the plungers. To the outlet
of the vessel or receiver I apply a diminishing valve of peculiar construction
for regulating the discharge of compressed air therefrom, and which valve is
also applicable to other similar purposes, or regulating the supply or discharge
of steam or other elastic fluids. It consists of a casing or box G, having a
brauch G on the top furnished with an ordinary safety valve H, with lever

page_text: and weight as usual, but this safety valve is not necessary to the proper
working of this diminishing valve. On the side of this branch is an outlet
pipe, shewn in dotted lines. Within the branch is fixed a perforated cylinder
or seating I, in which is a piston J, the rod attached to which is also fixed to
one side of a compressible hollow vessel K, which is constructed of two flexible
dishes fastened together air-tight. The other side of the vessel is fixed to a
hollow spindle L, which is also fixed by bush into the box, and passing
through a stuffing box is made air-tight therein. Within the vessel K are
two plates screwed on to a right and left hand screw pin M, which passes
loosley through the hollow spindle,and has a square at its bottom end for a
screw wrench to fit. Betwixt the plates and the sides of the vessel are a
series of spiral (or other) springs N to prevent colapse of the vessel and
render it flexible. It will be observed that when the pressure of the air in
the cylindrical vessel increases, the hollow flexible vessel will colapse or be
compressed in the same proportion and draw downward the piston, which will
thereby cover more or less or diminish the area of the perforations in the
seating, hence lessening the volume of air discharged in proportion to the
amount of compression such air has received. This construction and arrang-
ment of apparatus may be employed for compressing and discharging air
for other purposes as well as for working coal-cutting machines.
In witness whereof, I, the said William Leatham, have hereunto set my
hand and seal, this Twenty-sixth day of October, One thousand eight
hundred and sixty-five.
WILLIAM LEATHAM. (L.S.)