IMPROVE- MENTS IN MACHINERY FOR BORING, CUTTING, OR WORKING IN ROCK, COAL, AND OTHER MINERAL
Year: 1867

page_text: LETTERS PATENT to Frederick Bernard Doering, of Duke Street, in the
City of Westminster, Civil Engineer, for the Invention of "IMPROVE-
MENTS IN MACHINERY FOR BORING, CUTTING, OR WORKING IN ROCK, COAL, AND
OTHER MINERAL."
Sealed the 3rd March 1868, and dated the 4th September 1867.
PROVISIONAL SPECIFICATION left by the said Frederick Bernard Doering.
at the Office of the Commissioners of Patents, with his Petition, on the:
4th September 1867.
I, FREDERICK BERNARD DŒERING, of Duke Street, in the City of West-
minster, Civil Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN MACHINERY FOR BORING, CUTTING, OR WORKING IN Rock,
COAL, AND OTHER MINERAL," to be as follows:-
The first part of my Invention consists in an improved arrangement of
engine in which the main cylinder acts as a distributor of the motive fluid.
The main cylinder, in addition to its ordinary two ports for admitting the fluid
for producing the forward and back strokes of the piston has two ports in
communication respectively with the back end of the valve of the cylinder
and with the back end of a cylinder of the advance movement. In
addition to these ports the main cylinder has a central main supply port
or aperture at or about its centre in constant communication with the fluid

page_text: supply. The piston rod carries three pistons forming between them
two chambers; the forward chamber communicates with the outer air in
front of the cylinder by a passage formed through the piston. A constant
pressure is maintained against the forward end of the valve, the rod of which
carries four pistons, the two outer pistons forming the valve piston proper,
while the others close and open at the proper times the ports leading to the
main piston. The forward valve piston or forward face of the valve piston
proper is of smaller area than the back piston or back face. A constant
pressure is likewise always maintained at the front end of the advance move-
ment cylinder. As the main piston is making its forward stroke the port
communicating with the front end of the valve cylinder is put into communica-
tion by the back chamber of the main piston with the main supply port.
The fluid thus flows to the back end of the valve cylinder where, acting upon
a greater area than is acted upon by the constant pressure at the front end, it
overcomes the constant pressure and moves the valve forward; this puts the
main supply in communication with the front end of the main cylinder so that
the main piston is caused to make its back stroke; in this stroke it cuts off
the port communicating with the back of the valve cylinder, and the chamber
at the back of this cylinder then exhausts through the passage in the main
piston rod, so that the constant pressure at the front not being resisted moves
the valve back to open the port leading to the back of the main piston and so
on. In both strokes the main exhaust is through the body of the valve cylinder.
The piston of the advance cylinder is kept at the front by pressure exerted
at the back, which is of larger area than the front. In the forward stroke
of the main piston the port in communication with the back of this cylinder
is passed by the main piston only when the tool has cut to a determined depth
and the piston of the advance cylinder is therefore kept at the front end until
the main piston is able to make its full stroke when exhaust takes place
through the port, and the constant pressure on the front side of the piston
then drives the piston back and withdraws a paul carried by the piston from
its ratchet wheel ready to rotate this wheel and advance the engine at the
next stroke of the main piston. In some cases I reverse the action of the
engine before explained, that is to say, I maintain a constant pressure at
the back instead of at the front of the valve; the main exhaust, then takes
the place of the main supply, and vice versa. The port, in communication
with the advance, cylinder, instead of being placed so that it is behind the
piston after the completion of a full stroke may be placed so that it is behind
the middle partition of the piston; the advance piston is in this case moved
by pressure at the end of the forward stroke instead of in the manner before

page_text: explained. The rotary motion of the piston and tool may be effected by
means of a small cylinder, and suitable ports and gearing similar to those of
the advance cylinder, or by levers or other appliances in connection with the
valve rod; but I prefer to produce the rotary motion by the arrangement
about to be described, and this arrangement forms another part of my
Invention.
My arrangement for producing the rotary motion of the piston and tool
consists in the employment of a twisted, square, or cornered bar, or of a rod
with a spiral feather or groove in combination with other parts as follows:-
The back part of the piston rod is hollow to receive the twisted rod, the rear
end of which passes through the rear end of the cylinder and carries a ratchet
wheel. The twisted rod is a fixture longitudinally, but is free to turn on its
axis in one direction while a paul which takes into the ratchet wheel prevents
it turning in the other direction. In the back stroke of the piston the twisted
rod is held by the paul, and the piston rod which is formed internally to fit the
bar follows the twist and is caused to rotate; in the forward stroke the
twisted rod being free to rotate and being more easily rotated than the piston
the latter makes its stroke without rotating, while the twisted rod moves
round the paul riding over the ratchet tooth, or the piston may be made to
rotate in the forward and the bar in the back stroke, the alteration being
effected by reversing the direction of the twist.
The next part of my Invention relates to an arrangement of machinery for
under-cutting. The main feature in this arrangement is the combination of
a longitudinal travel and a transverse travel given to the engine and cutting
tool. The apparatus consists of a rectangular frame with columns for fixing
the same in position; two longitudinal bars of the frame form slides or guides
for a transverse frame carrying and forming a slide or guide for the engine.
When the cutting tool has cut to a certain determined depth, the piston of the
main cylinder opens a port in communication with one or more cylinders of
the longitudinal movement, whereby pauls in connection with these cylinders
move ratchet wheels the distance of one tooth. The ratchet wheels are keyed
on a transverse shaft, and the upper ends of rods, the lower ends of which are
centred in the lower part of the frame, are connected to crauks on this shaft
or to crank pins on the ratchet wheels, so that as the ratchet wheels and bar
rotate the rods are caused to move the transverse frame intermittently to one
end and then intermittently back to the other end of the longitudinal frame.
The teeth of the ratchet wheels may be so divided as to make the distance.
noved nearly uniform throughout. Sometimes instead of these rods I employ
xcentrics, the rotation of which causes the transverse frame to travel; or instead
:

page_text: of the rods or of excentrics and other parts as just explained I employ a longi-
tudinal threaded rod carrying a worm wheel geared into by a worm on the
spindle of a ratchet wheel, the paul of which is worked by a small cylinder in
communication with the main cylinder when the tool has cut a certain distance.
In this last arrangement when the transverse frame in its intermittent motion
reaches one end of its travel the communication with the small cylinder is
shut off, and communication is made with a second small cylinder carried on
the side of the engine frame opposite the first cylinder; this cylinder is likewise
fitted with a worm and ratchet arrangement, which acts and moves the
transverse frame in the reverse direction intermittently until the opposite end
of the longitudinal frame is reached, and so on; thus a cutting is made in
width about equal to the length of the longitudinal frame. As the tool cuts
to a depth sufficient to allow the main piston to make a full stroke the engine
is moved forward on the transverse frame preferably by the mode about to be
described: A socket on the cylinder cover receives a threaded bar which
passes through a nut in the back of the transverse frame and carries a ratchet
wheel; this wheel is rotated by a paul connected to the piston rod of a
cylinder which is actuated from the engine cylinder. When the ratchet wheel
rotates the threaded bar turns, and the engine is thus moved forward. The
rear end of the threaded bar is fitted with a hand wheel or other contrivance
to enable the engine to be moved back. If desired the columns may be fitted
with collars and other parts for carrying engines and tools.
The next part of my Invention relates to engines and carriages or stands
specially applicable to coal cutting. The chief features of the arrangements
are that the coal is chipped or cut by a series of blows, the cylinder advancing
in the direction of its length at the end of each blow, or as required according
to the work done, and when it has reached the end of its travel on the cradle,
it is returned to its original position by another cylinder, and the carriage on
which the engine is carried is moved laterally to commence a fresh cut;
during the moving back of the cylinder to commence a fresh cut, the piston is
prevented from working. I employ an engine and cylinder with twisted
turning bar, similar to what I have described in the first and second parts of
this Specification. On the front of the piston I fit a collar carrying two pins,
this collar can be rigidly clamped to the piston rod when a turning motion is not
required, the paul operating on the wheel of the twisted bar being in that case
thrown out of gear. The pins on the collar take into a slotted bar connected
with a paul, the slotted bar being curved at its front end so as to lift the
paul when the piston has completed a full stroke. The cradle supporting
the engine consists of two or more bars, one formed with ratchet teeth, those

page_text: on one half of the bar being formed in the opposite direction to those on the
other half, and both facing the centre; on one of the bars a piston is fixed
near the centre, which works in a cylinder adjacent and rigidly attached to
the main cylinder and packed at both ends. A constant pressure is main-
tained on the front side of the piston of the adjacent cylinder while the engine
is working, enabling the cylinders to advance when permitted by the paul
before mentioned being thrown out of gear by the advance stroke of the
piston. Attached to the adjacent cylinder are two other small cylinders, the
pistons of which are connected by a bar which projects a certain distance at
each end. During the working and advance of the main cylinder constant
pressure from a port communicating with the main supply, and hereafter for
distinction called port A', supplies the forward small cylinder, hereafter called
cylinder 1, with the air or other fluid at the back of its piston, keeping the
piston and that of the other cylinder, hereafter called cylinder 2, as well as the
bar, in their forward position, and admits air through a port, hereafter called
port B', in the forward small cylinder communicating with ports in a vertical
column hereafter explained: A paul taking into the back half of the ratchet
bar, and kept in position by a spring or otherwise, takes into a small cylinder,
(hereafter called.cylinder 3) attached to the main cylinder or other main part.
The piston of cylinder 2 during the working covers a port, hereafter. called A³,
communicating with the main supply, and just behind the piston of cylinder 2
is a port called C¹ which is free to the air, the back of cylinder 2 as well as
the front of cylinder 1 being open for exhausting.
Attached to the valve are
a cylinder and piston of such an area as will hold the valve over when pressure
comes upon this piston, so as to admit the motive fluid to the forward end of
the main piston and hold it at the back end of its, stroke as long as required.
When the working has proceeded so far that the front of the bar connecting the
pistons of cylinders 1 and 2 comes against a projection on the cradle the bar.
throws these pistons back, and port B¹ then exhausts the air, and port C¹
receives air from port A, and pressure is maintained in front of the pistou of
cylinder 2, the port A¹ of cylinder 1 being closed; port B¹ being in connection
with the front end of the large adjacent cylinder the pressure there is. now
exhausted, and port C¹ being connected with the back end of the same cylinder
pressure is obtained there, which tends to press this cylinder and the main
cylinder in a backward direction; port C¹ is also in connection with cylinder 3;
and the air acting upon the back of the piston of this cylinder draws the paul
out of the back half of the ratchet bar to allow the engine to be moved
backwards. At the back end of the cradle are two small cylinders, which I
will call cylinders 4 and 5, having between them one piston rod connecting

page_text: their two pistons, this piston rod projects forward to a greater length
than the back projection of the bar of cylinders 1 and 2. The piston of
cylinder 5 has a compartment in which constant pressure is maintained from
a port called hereafter A3; behind the piston of cylinder 4 is a port called A
When the main and
through which a constant pressure is maintained.
adjacent cylinders are carried back the piston rod of cylinders 4 and 5 is pressed
back by the adjacent cylinder or a suitable projection, whereby air is admitted
from port A³ to a port called B³ in communication with a cylinder or the valve
of a cylinder on a stand on the engine carriage, this cylinder being for moving
the carriage as hereafter explained. Before the pistons of cylinders 4 and 5
reach the end of their back stroke the projecting end of cylinders 1 and 2
comes against a projection on the cradle and moves the pistons of cylinders
1 and 2 into their forward position, releasing the valve of the main cylinder,
releasing the paul attached to cylinder 3, and removing the pressure from the
back to the front end of the piston of the adjacent cylinder, the whole of the
parts being now ready to commence a fresh cut.
The carriage on which this engine is supported is constructed as follows:-
A main frame mounted on wheels carries the vertical column before referred
to; this column is hollow and is fitted with two pistons working in opposite
directions; the rods of these pistons have at their ends suitable appliances for
gripping the floor and roof of the mine respectively, and the upper and lower
ends of the column are suitably packed. The outer area of each piston is
simply a small annular surface, the inner area being equal in diameter to the
interior diameter of the column. Constant pressure is maintained respectively
through ports which I will call As and A on the smaller annular surfaces of
these pistons; this constant pressure is overcome by pressure through a port
called. B' in communication with port B¹ such pressure acting upon both
pistons in the space between them and forcing the pistons outwards. When
the bar of cylinders 1 and 2 is moved back the air which exerts pressure
through ports B¹ and B is exhausted, and the constant pressures on the
annular surfaces then move the pistons of the column inwards and withdraw
the gripping appliances from contact with the floor and roof respectively,
allowing the carriage to be moved forward by means of the cylinder which I
will call cylinder 6, and before referred to, on the stand of the carriage. The
piston rod of this cylinder is attached to a bar which takes into ratchet teeth
at the side of the rails or elsewhere. Constant pressure is maintained on the
front of the piston of cylinder 6 through a port called A', and this pressure is
overcome when the rod of cylinders 1 and 2 is moved back by air from
port B³ in communication with the valve of cylinder 6, which valve has always

page_text: a constant pressure at one end. The vertical column carries a vertical collar,
which moves on its axis and may be clamped in any required position by
means of a bolt and nut in the flanges of the collar; the nut of this bolt may
be fitted with a worm wheel and worm worked by a handle. The collar may
be fitted so as to be moved up and down; it carries a horizontal collar, through
which a bar passes free to move on it axis and carrying at one end a third
collar at right angles to the second collar; another bar passes through the
third collar and carries the cradle on which the engine is supported.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Frederick Bernard Doering in the Great Seal Patent Office
on the 4th March 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
BERNARD DŒERING, of Duke Street, in the City of Westminster, Civil
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of September, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of
'Her reign did, for Herself, Her heirs and successors, give and grant unto
me, the said Frederick Bernard Doering, Her special licence that I, the said
Frederick Bernard Doering, my executors, administrators, and assigns, or such
others as I, the said Frederick Bernard Doering, 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 MACHINERY FOR BORING, CUTTING, OR WORKING.
IN ROCK, COAL, AND OTHER MINERAL," upon the condition (amongst others)
that I, the said Frederick Bernard Doering, my executors or adminis
trators, 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 Frederick Bernard Doering, do hereby
declare the nature of the said Invention, and in what manner the sanie

page_text: is to be performed, to be particularly described and ascertained in and by
the following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say.
My Invention relates, firstly, to an arrangement of machinery for under
cutting or cutting a groove in rock; and, secondly, to engines and carriages
or stands specially applicable to coal cutting.
The main feature in my arrangement for under cutting or groove cutting
is the combination of a longitudinal travel and a transverse travel given to
the engine and cutting tool. The arrangement is represented in side elevation
in Figure 1, in section in Figure 2, and in plan in Figure 3; Figure 4 is a
detached view.
The apparatus consists of a rectangular frame with columns B for fixing the
same in position; two bars A form slides for a frame C carrying and forming
a slide for the engine D. At every stroke of the main piston it opens a part a
in communication with a cylinder 6 (or more than one cylinder), whereby a
paul c in connection with the cylinder moves a ratchet wheel d the distance of
one tooth; the wheel d is keyed on the shaft e, and one end of rods f, f,
the other end of which is centred at 9, 9, is connected to cranks h, h, on this
shaft, so that as the ratchet wheel and shaft e rotate the rods f, f, are caused
to move the frame C intermittently to one end and then intermittently back
to the other end of the frame A. The teeth of the ratchet wheel may be so
divided as to make the distance moved nearly uniform throughout. Sometimes
instead of these rods I employ excentrics, the rotation of which causes the
frame C to travel. As the tool cuts to a depth sufficient to allow the main
piston to make a full stroke the engine is moved forward preferably as follows:
-A socket i on the cylinder cover receives a threaded bar k, which passes
through a nut in the back of the frame C and carries a ratchet wheel m;
this wheel is rotated by a pawl n connected to the piston rod of a cylinder o
which is actuated from a port in the engine cylinder. When the ratchet
wheel rotates the threaded bar turns, and the engine is thus moved forward.
The rear end of the threaded bar is fitted with a hand wheel or other contrivance
to enable the engine to be moved back. The cutting appliance may consist
of one broad tool, as shewn, or of a row of tools secured in a socket on the
front of the piston rod. If desired the columns B may be fitted with collars
and other parts for carrying engines and tools. Although I bave shewn the
cylinder as cast in a piece with or secured directly to the main cylinder it
'may be placed at any other convenient part of the frame.
I now proceed to describe the second part of my Invention, which relates
to arrangements of engines and carriages or stands specially applicable to

page_text: coal cutting. The chief features of the arrangements are that the coal is
chipped or cut by a series of blows, the cylinder advancing in the direction of
its length at the end of each blow, or as required, according to the work done,
and when it has reached the end of its travel on the cradle it is returned to
its original position by another cylinder, and the carriage on which the engine
is carried is moved laterally to commence: a fresh cut. During the moving
back of the cylinder to commence a fresh cut the piston is prevented from
working.
Figure 5 is a side elevation of the engine; Figure 6 is a longitudinal section
of the same through the centre of the main cylinder, and Figure 7 an end view
of the main cylinder; Figure 8 is an elevation of the carriage or stand;
Figure 9, an elevation at right angles to Figure 8; and Figure 10 a plan of
the carriage or stand.
.
.
.
a is the main cylinder, and 6 is its valve; the piston rod of this cylinder
carries three pistons, and the to-and-fro motion is produced in the manner
described in the Specification of my Patent of 10 June 1867, No. 17.04, and
shown in Figures 3 and 3*, Sheet 2, of the Drawings annexed thereto. The
rotary motion of the piston may be produced in any suitable manner; as
shown in the Drawings it is produced by means of a twisted bar c, the front
end of which is received in the back part of the piston rod, while the back end
of the bar passes through the rear end of the cylinder, and carries a ratchet
wheel d. The bar c is a fixture longitudinally, but is free to turn on its axis
in one direction, while a paul, e which takes into the wheel d prevents it
turning in the other direction. In the back stroke of the piston the bar c is
.held by the paul e, and the piston rod which is formed internally to fit the bar
follows the twist and is caused to rotate; in the forward stroke the bar'e
being free to rotate, and being more easily rotated than the piston, the latter
makes its stroke without rotating while the bar c moves round the paul riding
over the ratchet tooth, but to ensure that the bar c and not the piston shall
rotate in the forward stroke another ratchet wheel may be fitted on the
forward part or the piston rod, as shewn at d', a paul preventing the piston
rotating in the forward stroke. The piston rod has a groove or feather d³
corresponding with a feather or groove on the wheel d¹. If preferred the
piston may be made to rotate in the forward and the bar in the back stroke,
the alteration being effected by reversing the direction of the twist. On the
front of the piston rod I fit a collar f carrying two pins 9; the collar can be
rigidly clamped to the piston rod when a turning motion is not required, the
paul e operating on the wheel d of the twisted bar c, being in that case thrown
out of gear. The pins 9 on the collar f take into a slotted bar h connected

page_text: with a paul i, the slotted bar h being curved at its front end so as to lift the
paul when the piston has completed a full stroke. The cradle supporting
the engine consists of two or more bars k, k, one formed with ratchet teeth
l, m, those on one half of the bar being formed in the opposite direction to
those m on the other half, and both facing the centre as shown; on one of
the bars a piston n is. fixed near the centre, which works in a cylinder o
adjacent, and rigidly attached to the main cylinder a, and packed at both ends.
A constant pressure is maintained on the front side of the piston n of the
adjacent cylinder while the engine is working, enabling the cylinders a and o
to advance when permitted by the paul i being thrown out of gear by the
advance stroke of the main piston. Attached to the adjacent cylinder are
two other small cylinders 1 and 2, the pistons of which are connected by a
bar P which projects a certain distance at each end. During the working
and advance of the main cylinder a a constant pressure from a port A¹ com-
municating with the main supply supplies the forward small cylinder 1 with
the air or other fluid at the back of its piston keeping the piston and that of
the other cylinder 2, as well as the bar p, in their forward position, and admits
air through a port B₁ in the forward small cylinder 1 communicating with
ports in a vertical column of the carriage, and hereafter explained. A paul g
taking into the back half m of the ratchet bar, and kept in position by a
spring or otherwise, takes into a small cylinder 3 attached to the main
cylinder a or other main part. The piston of cylinder 2 during the working
covers a port A2 communicating with the main supply, and just behind the
piston of cylinder 2 is a port C2 which is free to the air, the back of cylinder 2
as well as the front of cylinder 1 being open for exhausting. Attached to
the valve are a cylinder and piston s of such an area as will hold the valve
over when pressure from port C¹ comes upon this piston, so as to admit the
motive fluid to the forward end of the main piston and hold it at the back
end of its stroke as long as required. When the working has proceeded so far
that the front of the bar p connecting the pistons of cylinders 1 and 2 comes
against a projection t. on the cradle the bar p throws these pistons back, and
port B¹ then exhausts the air, and port C¹ receives air from port A², and pressure
is maintained in front of the piston of cylinder 2, the port A¹ of cylinder 1
being closed, port B₁ being in connection with the front end of the large
adjacent cylinder o, the pressure there is now exhausted, and port C¹ being
connected with the back end of the same cylinder, pressure is obtained there,
which tends to press this cylinder and the main cylinder a in a backward
direction; port C is also in connection with cylinder 3, and the air acting
on the back of the piston of this cylinder draws the paul q out of the back

page_text: half m of the ratchet bar to allow the engine to be moved backwards; or the
piston of cylinder 3 may be actuated by an earlier port at the point C³ of
cylinder 2. At the back end of the cradle are two small cylinders 4 and 5,
having between them one piston rod t¹ connecting their two pistons; this
piston rod projects forward to a greater length than the back projection of the
bar p of cylinders 1 and 2. The piston of cylinder 5 has a compartment u in
which constant pressure is maintained from a port A³. Behind the piston of
cylinder 4 is a port A' through which a constant pressure is maintained;
when the main and adjacent cylinders a and o are carried back the piston rod t¹
of cylinders 4 and 5 is pressed back by the adjacent cylinder o or a suitable
projection (which may be provided with a spring if necessary), whereby air is
admitted from port A³ to a port B³ in connection with a cylinder or the valve of
a cylinder 6 (Figures 8 and 10) on a stand on the engine carriage, this cylinder
being for moving the carriage, as hereafter explained. Before the pistons of
cylinders 4 and 5 reach the end of their back stroke the projecting end of the
bar p of cylinders 1 and 2 comes against a projection von the cradle and
moves the pistons of cylinders 1 and 2 into their forward position, releasing
the valve of the main cylinder, releasing the paul g attached to cylinder 3,
and removing the pressure from the back to the front end of the piston of
the adjacent cylinder o, the whole of the parts being now ready to commence
a fresh cut. Any of the ports before referred to may be regulated by a screw
or cock.
:
The carriage on which this engine is supported is constructed as follows:-
A main frame E mounted on wheels F carries the vertical column G before
referred to; this column is hollow- and is fitted with 2 pistons H, H,
working in opposite directions; these pistons or the column are fitted with
feathers to prevent rotation. The rods of these pistons have at their ends
suitable appliances I, I, for gripping the floor and roof of the mine respectively,
and the upper and lower ends of the column are suitably packed. The outer
area of each piston H, H, (that is to say, the upper area of the upper piston
and the lower area of the lower piston) is simply a small annular surface,
the inner area being equal in diameter to the interior diameter of the column
G. Constant pressure is maintained respectively through ports A5 and AⓇ on
the small annular surfaces of these pistons; this constant pressure is overcome
by pressure through a port B in communication with the port B₁ of the
engine, such pressure acting upon both pistons H, H, in the space between
them and forcing the pistons outwards; when the bar p of cylinders 1 and 2
is moved back the air which exerts pressure through ports B¹ and B is
exhausted, and the constant pressures. on the annular surfaces then move the

page_text: pistons H, H, inwards and withdraw the gripping appliances I, I, from contact
with the floor and roof respectively, allowing the carriage to be moved by
means of the cylinder 6 before referred to; the piston rod of this cylinder is
attached to a bar w, which takes into ratchet teeth at the side of the rails
or elsewhere. Constant pressure is maintained on the front of the piston of
cylinder 6 through a port- A7, and this pressure is overcome when the rod of
cylinders 1 and 2 is moved back by air from port B³ in communication with
the valve of cylinder 6, which valve has always a constant pressure at one end.
I prefer in most instances to use only one of the pistons H, H, viz., the top
piston. The vertical column G carries a vertical collar K which is free to
move on its axis and may be clamped in any desired position by means of a
bolt and nut L in the flanges of the collar; the nut of this bolt may be fitted
with a worm wheel and worm worked by a handle. The collar K may be
fitted so as to be moved up and down; it carries a horizontal collar M through
which a bar N passes free to move on its axis and carrying at one end a third
collar O; at right angles to the second collar M another bar P passes through
the third collar and carries the cradle on which the engine is supported, as
seen in Figure 8. The dottted line 2, 2, Figure 8, represents the line through
which the section, Fig. 6, is taken.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim as my "Im-
provements in Machinery for Boring, Cutting, or Working in Rock, Coal, and
other Mineral,"
First. The combination with the main cylinder of a small cylinder and
other parts, substantially as herein-before described with reference to Figures
1 to 4 for moving the frame, carrying the engine intermittently to one end
and then intermittently back to the other end of the frame or bars on which it
slides.
Second. The arrangement consisting of the shaft e, rods f, and cranks h,
operated at every stroke of the piston for the purpose of causing the frame C
to reciprocate on the bars A, substantially as herein-before described with
reference to Figures 1 to 4.
Third. The general combination and arrangement of parts of machinery as
herein-before described and represented in Figures 1 to 4.
Fourth. The combination with the main cylinder and adjacent cylinder
(Figures 5 and 6) of the two cylinders 1 and 2, with the bar connecting their
two pistons in such manner that when the engine has reached the front end
of its travel on the cradle the necessary ports and communications are opened
and closed to produce the backward movement of the main and adjacent

page_text: cylinders, the paul 9 being at the same time or immediately before freed from
the ratchet bar, all substantially as herein-before described.
Fifth. The combination with the valve of the main cylinder of the cylinder
and piston s, Figures 5 and 6, operated in the manner and for the purpose
herein-before described.
Sixth. The arrangement as herein-before described with reference to
Figures 5 and 6 for reversing the motion and returning the parts into position
to commence a fresh cut when the engine has reached the back end of its
travel on the cradle.
Seventh. The arrangement as herein-before described of the cylinders
4 and 5 (Figures 5 and 6), with their piston rod t for the purpose of
operating on a cylinder or the valve of a cylinder for moving the carriage
forward.
Eighth. The general combination or arrangement of parts herein-before
described and represented in Figures 5 and 6.
Ninth. The construction and arrangement as herein-before described of the
cylinder 6 (Figures 8, 9, 10), the piston of which is operated from a cylinder
on the engine cradle so as to move the carriage or stand forward as herein-
before explained.
In witness whereof, I, the said Frederick Bernard Doering, have here-
unto set my hand and seal, this Fourth day of March, in the year of
our Lord One thousand eight hundred and sixty-eight.
F. B. DŒERING.
L.S.)