IMPROVEMENTS IN TUNNELLING AND QUARRYING SLATE AND OTHER MINERALS, AND IN MACHINERY USED FOR THOSE PURPOSES
Year: 1867

page_text: LETTERS PATENT to William Fothergill Cooke, of Aberia, near Car-
narvon, North Wales, for the Invention of "IMPROVEMENTS IN TUNNELLING
AND QUARRYING SLATE AND OTHER MINERALS, AND IN MACHINERY USED FOR
THOSE PURPOSES."
Sealed the 6th March 1868, and dated the 11th September 1867.
PROVISIONAL SPECIFICATION left by the said William Fothergill Cooke
at the Office of the Commissioners of Patents, with his Petition, on the
11th September 1867.
I, WILLIAM FOTHERGILL COOKE, of Aberia, near Carnarvon, North Wales,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
TUNNELLING AND QUARRYING SLATE AND OTHER MINERALS, AND IN MACHINERY
USED FOR THESE PURPOSES," to be as follows:-
In the Specification of a former Patent granted to myself and George
Hunter on the 12th day of February 1866 (No. 433) was described à machine
for cutting tunnels. When
When using this machine I have found that after
causing the machine to cut forward a distance into slate or stone and form
an annular groove therein, the time occupied in removing the central core by
hand through the middle of the machine is about three times as long as the
time taken by the machine to cut the groove into the slate or mineral, and
consequently the machine was idle for 9 hours out of every 12.
According to my present Invention I combine and use with such cutting
machine (or other cutting machine by which an annular groove is cut in the

page_text: rock or mineral) a traversing machine on to which the cutting machine when it
has made its forward cut in one tunnel, say to the depth of about 2 feet, and
has been run back on its rails to the mouth of the tunnel, is received, and is
by it shifted sideways in order that it may be run forward on to a second line of
rails and caused to cut a second tunnel parallel with and slightly intersecting
the tunnel first formed. When the machine has made its cut in the second
tunnel it is similarly run back and shifted sidewise by the traversing machine
to be again run forward and caused to cut a third tunnel slightly intersecting
the second tunnel, and if desired the machine may again be similarly shifted
sidewise for cutting another tunnel, afterwards the machine is moved back and
again caused to cut in the first tunnel. When the cutter of the machine is
made to revolve in the direction of the hands of a watch then the tunnel first
formed should be on the right hand of the other tunnels; the first tunnel
should also always take the lead of the second tunnel, and the second of the
third, as by this means all dust or loose pieces are swept by the cutter into
the tunnel on its right hand; a blast or shot hole can also be driven from the
leading tunnel across the natural: split or cleavage of the slate (if slate is
being worked) at the end of the cut in the tunnel next to it on its left hand,
and thus a great saving of time is effected in removing the core of slate or
mineral after the machine has made its cut. Another advantage arising out
cut or tunnel next to it, is that
of causing one cut or tunnel to intersect the
the tools can be seen at the intersection, and if any of them are blunt they
can readily be replaced. By the system of quarrying and' tunnelling above
described a far greater quantity of slate may be removed in a given time by
the machine than when the machine is employed for cutting one tunnel only.
The traversing machine may be composed of a truck carrying on its upper
surface a pair of short rails which can be brought to coincide with the ends of
either one or other of the lines of rail, leading from the tunnels, the truck
being for this purpose supported on, rails laid at, right angles to the lines of
rail, leading from the tunnels, or in place of running the machine back on to
a truck the ends of all the lines of rail from the tunnels may be led to a
turntable by which the cutting machine, may, be shifted from one line of rails
to another, or, a, turntable at the end of each line of rails may be employed,
the. turntables being so placed that they can be run. from, one. turntable to
another, or other means might be adopted, for shifting, the cutting machine
from the line of rails of one tunnel to the line, of rails of another tunnel.
When opening slate quarries, where the slate, is vertical or nearly so I in
some cases, after, running. three, or more parellel tunnels into the slate, as
above described, run parallel therewith and on a lower floor or level, three.or

page_text: I
more similar tunnels, and when the solid rock is reached by the lower tunnels
carry a shaft up in the usual way to the upper tunnels, square the opening
sufficiently, and then by means of a vertical cutter such as described in the
Specification of the Patent before referred to, form in the slate between the two
sets of tunnels vertical cuts about 9 or 10 feet apart, the machine carrying these
vertical cutters will be fixed to carriages travelling on the two floors. By
this means I open a free face for working the slate rock between the floors,
winning the slate between the cuts.
When quarrying or tunnelling through slate, the grain of which is lying at
a considerable angle to the line of the tunnel, there is great difficulty in
blasting out the slate at all, and even when blasting is employed the whole of
the slate is shattered to pieces; to obviate this, I, according to this part of my
Invention employ a tool of the following construction for cutting away at the
back of a cylindrical core, and so facilitate its being detached and removed.
The tools for cutting away at 'the back of a cylindrical core may be applied
to the cutter which produces the annular cut into the slate or mineral, but
preferably the axis of the cutting tool is carried in bearings on a truck or
carriage, which is made lighter than the tunnelling machine.
The cutting tools which are to cut away at the back of the core are carried
by three or it might be other number of flat springs, which at their ends are
connected to segments or parts of the circumférence of the cylindrical cutter
which cuts the annular groove, or, as before suggested, it might be to other
segments of a circle of the same diameter; one end of each spring is rigidly
fixed to the segment or circular cutter, whilst the other end can be set 'free to
allow the spring to bend or straighten itself. Each spring when unbent or at
rest is concave to the segment or circular cutter, but when the tool is being
inserted to the back of the annular cut previously made by the machine the
springs are bent to a curve corresponding with the annular grove, into which
they are to be introduced. When the cutting tool has been introduced to
the back of the groove it is caused to revolve, and one end of each spring is
set free; the springs then endeavour to come to their normal concave position,
and thus the cutting tools are pressed inwards and caused to cut away at the
back of the cylindrical core which had previously been cut around' by another
or other cutting tools.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Fothergill Cooke in the Great Seal Patent Office
on the 11th March 1868.:
TO ALL TO WHOM THESE PRESENTS. SHALL COME, I, WILLIAM
FOTHERGILL, COOKE, of Aberia, near Carnarvon, North Wales, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh 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 William Fothergill Cooke, Her special licence that 1, the said William
Fothergill Cooke, my executors, administrators, and assigns, or such others
as I, the said William Fothergill Cooke, 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 TUNNELLING AND QUARRYING SLATE AND OTHER MINERALS,
AND IN MACHINERY USED FOR THESE PURPOSES," upon the condition (amongst
others) that I, the said William Fothergill Cooke, my executors. or admi-
nistrators, 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 William Fothergill Cooke, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
:
.In the Specification of a former Patent granted to myself and George
Hunter on the 12th day of February 1866 (No. 433) was described a
machine for cutting tunnels. When using this machine I have found that after
causing the machine to cut forward a distance into slate or stone and form
an annular groove therein the time occupied in removing the central core
by hand through the middle of the machine is about three times as long as
the time taken by the machine to cut the groove into the slate or mineral
and consequently the machine was idle for 9. hours out of every 12.

page_text: According to [my present Invention I combine and use with such cutting
machine (or other cutting machine by which an annular. groove is cut in the
rock or mineral) a traversing machine on to which the cutting machine
when it has made its forward cut in one tunnel, say to the depth of about 2
feet and has been run back on its rails to the mouth of the tunnel, is received
and is by it shifted sidewise, in order that it may be run forward on to a
second line of rails and caused, to cut a second tunnel parallel with and
slightly intersecting the tunnel first formed. When the machine has made
its cut in the second tunnel it is similarly run back and shifted sidewise by
the traversing machine, to be again run forward and caused to cut a third
tunnel slightly intersecting the second tunnel, and if desired the machine
may again be similarly shifted sidewise for cutting another tunnel; afterwards
the machine is moved back and again caused to cut in the first tunnel:
When the cutter of the machine is made to revolve in the direction of the
hands of a watch then the tunnel first formed should be on the right hand
of the other tunnels the first tunnel should also always take the lead of
the second tunnel, and the second of the third, as by this. means all dust or
loose pieces are swept by the cutter into the tunnel on its right hand. - A
blast or shot hole can also be driven from the leading tunnel across the
natural split or cleavage of the slate (if slate is being worked) at the end of
the cut in the tunnel next to it on its left hand, and thus a great saving of
time is effected in removing the core of slate or mineral after the machine
has made its cut....
.
Another advantage arising out of causing one cut or tunnel to intersect the
cut or tunnel next to it is that the tools can be seen at the intersection, and
if any of them are blunt they can readily be replaced. By, the system of
quarrying and tunnelling above described a far greater quantity of slate may be
removed in a given time by the machine than when the machine is employed
for cutting one tunnel only. The traversing machine may be composed os
a truck carrying on its upper surface a pair of short rails which can be brought
to coincide with the ends of either one or other of the lines of rail. leading
from the tunnels, the truck being for this purpose supported on rails laid
at right angles to the lines of rail leading from the tunnels; or in place of
running the machine back on to a truck the ends of all the lines of rail from
the tunnels may be led to a turntable, by which the cutting machine may
be shifted from one line of rails to another; or a turntable at the end of each
line of rails may be employed, the turntables being so placed that they can
be run from one turntable to another; or other means might be adopted for
shifting the cutting machine from the line of rails of one tunnel to the linȧ

page_text: of rails of another tunnel.. When opening slate quarries where the slate is
vertical or nearly so, I in some cases after running three or more parallel
tunnels into the slate as above described run parallel therewith and on a
lower floor or level three or more similar tunuels, and when the solid rock is
reached by the lower tunnels I.carry a shaft up in the usual way to the
upper tunnels, square the opening sufficiently, and then by means of a
vertical cutter, such as described in the Specification of the Patent before
referred to, form in the slate between the two sets of tunnels vertical cuts
about 9 or 10 feet apart; the machine carrying' these vertical cutters will be
fixed to carriages travelling on the two floors, or other arrangements for
making the vertical cuts might be employed. By this means I open a free
face for working the slate rock between the floors, winning the slate between
the cuts. When the ground on which the tunnelling machine is to commence
operations lies as it often does on the steep side of a mountain a substantial
timber base is essential to insure steadiness of action. Figures 1 and 2 in
the accompanying Drawing show arrangements which in practice. have
worked most satisfactorily.
A, Figure 1, shows the traverser, for moving the tunneller sidewise in
elevation on its platform B and carrying the tunneller C ready either to be
transferred sidewise to tunnels T¹ or T or to enter tunnel T. The chain E
worked by the crab D, or other convenient power draws the traverser to the
position required. Figure 2 shows the details of the traverser in plan. Besides
shifting the tunneller from one tunnel to another the traverser is in constant
use for the removal of trucks or waggons loaded with the rock or slate removed
from the cores previously cut by the tunneller and in conveying them to the
tramway leading to the workshops or rubbish heap. Figure 3 shows the rails
arranged within the tunnels for the carriage of the tunneller; they are made
of angle iron in convenient, short lengths and simply laid on the bottom of the
smoothly cut tunnel, being bolted together and kept in gauge by cross ties, as
shown on a large scale at Figure 5. This form of rail serves also for the
ordinary trucks and waggons employed in removing the cores.
As the tun-
neller is advanced two feet or two feet six inches at each cut short lengths
of rail are employed for its support, eked out if necessary by iron plates of a
few inches width, these short pieces being replaced from time to time by the
ordinary rails.
Care must be taken to insure the rails being straight and free.
from lumps of rock or other impediments when running the tunneller in or
out, as the tunneller only clears itself by about three-quarters of an inch all
round, and if the rail be negligently laid the cutting plates would rub against
the sides of the tunnel, causing when moving at the rate of one hundred feet.

page_text: a minute a jerking resistance to the engine or other power in use.... As. the
cutting blades of the tunneller are divided into segments the spaces between.
the segments admit of ample room for the rails, and the back tools of the
cutters which enlarge the radius of the tunnel from half to three-quarters of
an inch are hinged back when the cut is completed and allow of abundant.
freedom for the movement of the machine and the thickness of the angle-rail.
When it is necessary to work the tunneller without the traverser the rails,
may be dispensed with, and the tunneller travels upon the bottom of the
tunnel; the back tools of the cutter are then removed as the further enlarge-
ment of the tunnel becomes unnecessary for the rails or freedom of motion of
the machine.
Figure 4 shows one of many arrangements, which must be varied with the
circumstances of the ground, by which a wire rope may be made to work the
tunneller in alternate tunnels and enabled to accommodate itself to the advance.
or retrograde movements of the tunneller. F is a strong timber framing on,
which a saddle G mounted with guide pulleys travels on small rails and is
readily shifted to the front of the tunnel in which the tunneller is about to be
worked and there firmly fixed. H represents a counterweight on an incline F¹
by which a proper strain is kept on the wire rope whilst the rope can accom-
modate itself to the advance of the machine by the rise of the counterweight
truck up the incline. To avoid frequent splicings of the rope considerable
lengths of incline or of counterweights carried over pulleys in any convenient,
form allowed by the nature of the ground should be provided. Hand-H",
indicate the points at which power may be applied to put in motion either the
wire rope for working the tunneller or a chain or rope for pulling it in or out;
of the tunnel. When the traverser has to be fixed within a set of tunnels,
either to change the direction of the workings or to obviate the necessity of,
running the tunneller to and fro after each cut for an inconvenient distance, a.
form of traverser like that shown at Figures 6 and 7 is preferable as entailing
less work in, cutting away the rock for the admission of simple cross rails
instead of the timber framing, as in Figures 1 and 2 previously described, for
traversing the, machine, in other positions where the lateral space is confined,
but length, is at command; as in the continuance of a set of tunnels already.
cut a turntable becomes the most convenient form for traversing the machine
sideways or even in a fresh direction; the turntable may then be sunk in
tunnel T, Figure 1, a little distance in the rear of the already opened work,
and the tunneller being placed on the turntable, after a little of the rock has
been cut away to allow of the machine standing at a slight angle from the
tunnel, the machine is set to work till it has cut its way sidewise on a gentle

page_text: curve through the ridge of rock between tunnels T and T and made its
way into tunnel T'; the machine is then brought back on to the turntable
and turned equally to tunnel T till it has cut sidewise into that tunnel;
then the three tunnels can be carried forward in alternate order as before.
As before stated the tunnels are by preference in all cases made to intersect
one another, as shown in the Drawing. A tunnelling machine working in
combination with a traversing machine might however be employed, although
not so 'advantageously, for cutting a row of parallel tunnels in close proximity
to one another, and the slate or mineral left standing between the tunnels
might afterwards be knocked away..
By the above-described plan of opening out rock by a series of parallel
tunnels a very large amount of progress may be made in a short time, and
the system is applicable to beds of rock, like the Bath stone and slate, more
especially where the slate rock stands nearly or quite vertical, which is very
extensively the case in North Wales. The more usual practice in such
vertical slate rock is to remove gradually the top and one face of the
mountain till the solid slate rock is reached and can then be worked on floors
or terraces, as at the celebrated 'quarries of Penrhyn and Llanberis. Many
years of unremunerative labor and the sinking of a large dead capital must
precede any commercial return; but by carrying out the system of quarrying
by tunnels above described the heart of the slate bed may be reached by a
single machine in a few weeks, and then by the traversing arrangements
several tunnelling machines may be started at the same time from the three
main tunnels T, T, T, at right angles to them to clear a ceiling or roof to
a succession of future chambers, whilst a large proportion of the slate is
saved from the cores cut by the machines. When opening slate quarries
where the slate is vertical or nearly so I in some cases after running three
or more parallel or main tunnels T, T", T, into the slate as above described
run parallel therewith and nearly vertical below them on a lower floor.or.level
three or more similar tunnels, and when the solid rock is reached by the lower
tunnel I carry a shaft up in the usual way to the upper tunnels, square the
opening sufficiently, and then by means of a vertical cutter, such as described
in the Specification of the Patent before referred to form in the slate between
the two sets of tunnels vertical cuts about nine or ten feet apart. The machine.
carrying these vertical cutters will be fixed or framed to two carriages
travelling on the two floors, or other arrangements of cutting apparatus might
be employed. By this means. I open a free face for working the slate rock..
between the floors, winning the slate between the cuts. From the long and
deep gallery thus formed the lateral chambers already unroofed by the process.

page_text: described may be opened on either or on both sides, leaving at suitable intervals
walls of sufficient strength to sustain the roof. The danger from opening
underground chambers in vertical slate rock lies in the unsafe state in which
the roof is left by the shattering from the powder in blasting; other objections
include the extreme slowness of the progress made and the entire destruction
of the rock removed, each step therefore is accompanied, with danger, heavy
expenditure, and waste; whereas by the system of working tunnelers with
traversing arrangements a clean roof or ceiling is rapidly made, in which any
unsafe piece of rock is at once detected and pinned up by iron bolts in the
usual way, and good rock is preserved and manufactured from the commence-
ment, sufficient not only to pay the expences of tunnelling, but to leave a
profit on the slates and slabs made from the cores. The cutting of a ceiling
or roof, by tunnels has been successfully carried out for the first time on the
plan above described under slate lying obliquely. The application therefore
is not: confined to vertical slate rock. When quarrying or tunnelling through
slate,. the grain or cleavage of, which is lying at a considerable angle to the
line of the tunnel, there is great difficulty in blasting out the slate at all, and
when blasting is employed the whole of the slate is shattered to pieces; to
obviate this I according to this part of my Invention employ tools of the
following construction for cutting away at the back of a cylindrical core and so
facilitate its being detached and removed. The tools for cutting away at the
back of a cylindrical core may be applied to the cutter which produces the
annular cut into the slate or mineral; but preferably the axis of the cutter is
carried in bearings on a truck or carriage which is made lighter than the
tunnelling machine, as the cutters are only required to revolve without
advancing. The cutting tools which are to cut away at the back of the core are
carried by three or it might be other number of flat springs, which at their
ends are connected to segments or parts of the circumference of the cylindrical
cutter which cuts the annular groove, or as before suggested it might be to other
segments of a circle of the same diameter. One end of each spring is rigidly
fixed to the segment or circular cutter, whilst the other end can be set free to
allow the spring to bend or straighten itself. Each spring when unbent or at
rest is concave to the segment or circular cutter, but when the tool is being
inserted to the back of the annular cut previously made by the machine the
springs are bent to a curve corresponding with the annular groove into which
they are to be introduced. When the cutting tool has been introduced to the
back of the groove it is caused to revolve and one end of each spring is set
free; the springs then endeavour to come to their normal concave position, and
thus the cutting tools are pressed inwards and caused to cut away at the back of
:

page_text: the cylindrical core which had previously been cut around by another or other
cutting tools.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that what I claim is,—
First. Tunnelling or quarrying slate and other minerals with a tunnelling
machine working in combination with a traversing machine to cut parallel
tunnels into the slate or mineral, as herein described.
Second. .Tunnelling or quarrying slate and other minerals with a tunnelling
machine, cutting into the slate or mineral parallel tunnels intersecting one
another, as herein described.
Third. The quarrying slate by cutting into the slate two parallel rows of
tunnels, one above the other, or at a distance from one another, and afterwards
sawing or cutting away the block of mineral between the two rows of tunnels,
as herein described.
Lastly. I claim constructing tools in the manner herein described for cutting.
away at the back of a circular block of slate or mineral which has had a groove
cut around it by a tunnelling machine.
In witness whereof, I, the said William Fothergill Cooke, have here-
unto set my hand and seal, this Ninth day of March, in the year'
of our Lord One thousand eight hundred and sixty-eight.
WILLIAM FOTHERGILL COOKE. (L.S.)