IMPROVEMENTS IN PAVEMENTS AND IN FASHIONING STONE TO BE USED AS PAVEMENTS, AND IN MACHINERY OR APPARATUS TO BE EMPLOYED IN THE MANUFACTURE OR PRODUCTION OF THE SAID IMPROVED PAVEMENTS
Year: 1876

page_text: LETTERS PATENT to Thomas Lawrie, of 4, Queen Street Place, Cannon Street,
in the City of London, for the Invention of "IMPROVEMENTS IN PAVEMENTS
AND IN FASHIONING STONE TO BE USED AS PAVEMENTS, AND IN MACHINERY OR
APPARATUS TO BE EMPLOYED IN THE MANUFACTURE OR PRODUCTION OF THE
SAID IMPROVED PAVEMENTS."
Sealed the 9th June 1876, and dated the 4th January 1876.
PROVISIONAL SPECIFICATION left by the said Thomas Lawrie at the Office
of the Commissioners of Patents, on the 4th January 1876.
THOMAS LAWRIE, of 4, Queen Street Place, Cannon Street, in the City of
London. "IMPROVEMENTS IN PAVEMENTS AND IN FASHIONING STONE TO BE USED
AS PAVEMENTS, AND IN MACHINERY OR APPARATUS TO BE EMPLOYED IN THE MANU-
FACTURE OR PRODUCTION OF THE SAID IMPROVED PAVEMENTS."
My said improvements in paving consists, firstly, in grooving the surface of
Yorkshire or other stone flags in a planing machine in which as many grooving
tools are fixed as it is intended to produce parallel grooves in the surface of the
stone, whether the same are to remain as merely parallel grooves or be crossed with
another series of grooves at right or any other angles, and which simple grooving
may constitute the whole work to be done to the said flags, but for most purposes
I take the grooved stones to a second machine, in which a series of diamond drills
are arranged so that a series of holes of any desired diameter may be drilled in a
line at the junction of the cross grooves before named. The drill for this purpose
may be made of a tubular form, with a large portion of the circle cut away. In
the remaining portion a piece of carbon, commonly called a "black diamond," or
other sufficiently hard gem or substance, is set, and which forms the revolving
cutting tool or drill, which cuts an annular groove, leaving a core, which drops out
when the stone is entirely perforated.
I prefer to set the carbon or other cutter so that it projects downwards, and also
externally and internally, from the surface of the metal in which it is set, so that
a single piece is capable of forming the annular drill.
:
In the foot pavement now used in public thoroughfares the hollow parts worn by
the usual traffic are found to retain water long after it has ceased to fall thereon;
I. therefore groove and perforate the stone slabs used for such purpose in such
manner that the rain falling thereon may be conveyed either direct to the side
gutter or be passed through suitable perforations made at short intervals in the
:

page_text: stone or slate slabs, and which perforation may communicate with channels formed
below the stone or be allowed to pass off simply through the bed of sand or shingle
on which the stones are laid. This latter mode is greatly to be preferred in all
foot pavements in which trees are planted, as the whole surface of the pavement
may if needful be utilized in supplying water to their roots instead of employing
a comparatively small area of iron grating round each tree. The grooving and per-
forating, or either of them, may be made to form various patterns and of different
sizes, but for general purposes I prefer to form V shaped grooves crossing each other
at right angles with a hole bored through the stone, at their intersection; such
grooved stones will also afford a better foothold than the uniform plain surfaces at
present in general use, and will for that reason be found especially suitable for the
platforms of railway stations, courtyards, and for the floors of certain buildings.
These perforated slabs are also well adapted to the paving of hothouses, green-
houses, or other places where the roots of trees or plants are to be more or less
covered by a stone floor. Such perforated slabs may also be used to cover the
spaces occupied by hot water pipes below the floor in hothouses, greenhouses, and
other buildings, the perforations in that case being of a larger size or more
numerous, so as to allow a free circulation of air to take place.
Slabs of stone may also be perforated in the manner herein-before described
with numerous holes, in which suitably moulded pieces of glass may be imbedded
for the purpose of giving light to the lower floors of buildings, areas, &c. In some
cases this system of perforating stone for ventilating floors may be made use of as
a means of ornamentation by inserting perforated ornamental tiles in a rebate formed
around each perforation.
°
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Lawrie in the Great Seal Patent Office on the 4th July
1876.
THOMAS LAWRIE, of 4, Queen Street Place, Cannon Street, in the City of London.
"IMPROVEMENTS IN PAVEMENTS AND IN FASHIONING STONE TO BE USED AS PAVE-
MENTS, AND IN MACHINERY OR APPARATUS TO BE EMPLOYED IN THE MANUFACTURE
OR PRODUCTION OF THE SAID IMPROVED PAVEMENTS."
My improvements in paving consist, firstly, in grooving the surface of Yorkshire
or other stone flags or alates in a planing machine in which as many grooving tools
are fixed as it is intended to produce parallel grooves in the surface of the stone,
whether the same are to remain as merely parallel grooves or be crossed with
another series of grooves at a right or other angle, and which simple grooving may
constitute the whole work to be done to the said flags. On Sheet A of the
annexed Drawings I have shown at Figure 1 the face of a paving stone simply
grooved in this manner, but for most purposes I take the grooved stones to a second
machine, in which a series of diamond drills are arranged so that a series of holes
of any desired diameter may be drilled in a line at the junction of each of the cross
grooves before named, as shewn at Figure 2, Sheet A, where a round hole extending
entirely through the stone is shown at the crossing of each of the diagonal grooves.
A section through the drilled hole and the cross grooves is shown on a larger scale
at Figure 3 on the same Sheet. The drill for this purpose may be made of a
tubular form with a large portion of the circle cut away. In the remaining portion
a piece of carbon, commonly called a black diamond, or other sufficiently hard gem
or substance, is set, and which forms the revolving cutting tool or drill, which cuts
an annular groove, leaving a core, which drops out when the stone is entirely
perforated.
I prefer to set the carbon or other cutter so that it projects downwards, and also
externally and internally, from the surface of the metal in which it is set, so that a
single piece of carbon or diamond is capable of forming an annular drill.

page_text: In the foot pavement now used in public thoroughfares the hollow parts worn by
the usual traffic are found to retain water long after it has ceased to fall thereon';
I therefore groove and perforate the stone or slate slabs used for such purpose in
such manner that the rain falling thereon may be conveyed either direct to the side
gutter or be passed through suitable perforations made at short intervals in the
slate or stone slabs, and which perforations may communicate with channels formed
below the stone or be allowed to pass off simply through the bed of sand or shingle
on which the stones are laid. This latter mode is greatly to be preferred in all foot
pavements in which trees are planted, as the whole surface of the pavement if
needful may be utilized in supplying water to their roots instead of employing a
comparatively small area of iron grating around each tree. The grooving and per-
forating, or either of them, may be made to form various patterns and of different
sizes, but for general purposes I prefer to form V shaped grooves crossing each
other at right angles, with a hole bored through the stone at their intersection;
such grooved stones will also afford a better foothold than the uniform plain surfaces
at present in general use, and will for that reason be found especially suitable for
the platforms of railway stations, courtyards, and for the floors of certain buildings.
These perforated slabs are also well adapted to the paving of hothouses, green-
houses, or other places where the roots of trees or plants are to be more or less
covered by a stone floor. Such perforated slabs may also be used to cover the
spaces occupied by hot-water pipes below the floor in hothouses, greenhouses, and
other buildings, the perforations in that case being of a larger size or more
numerous so as to allow a free circulation of air to take place.
Slabs of stone or slate may also be perforated in the manner herein-after
described with numerous holes, in which suitably moulded or shaped pieces of glass
may be embedded for the purpose of giving light to the lower floors of buildings,
areas, &c. In some cases this system of perforating stone for ventilating floors may
be made use of as a means of ornamentation by inserting perforated ornamental
tiles in a rebate formed round each perforation.
A drill suitable for these purposes is shown in section at Figure 4, and in
elevation at Figure 5, on Sheet A. The piece of carbon, diamond, or other hard
gem a is secured firmly into the steel tubular tool b by beating down the soft steel
close around the cavity in which the gem is embedded. By this arrangement a
single piece of carbon is capable of cutting an annular channel entirely through
the stone. The round solid part b¹ of the drill serves to fix it into the spindle by
which it is driven. Holes so drilled may be made to give a more or less orna-
mental appearance to the perforated stone, depending on their relative position or
on being more or less run into each other, as shown at Figure 6, Sheet A. Such
stones may be used in floors over hot water pipes or for ventilating or other purposes.
So likewise when a more or less ornamental effect is desired the holes in the stone
may be made of larger diameter and a rebate formed round their upper angle, into
which a perforated tile or metal grating may be inserted, as shown in section at
Figure 7. The tile is shown in plan at Figure 8, Sheet A.
In some cases a plain tile or piece of glass or marble may be inserted, as
shown in section at Figure 9, Sheet A.
It will be observed that in drills so constructed, in which a single diamond only
is employed, and which are used for the purpose of perforating stones of a definite
thickness, that the core which is cut out by the drill cannot pass up through the
drill, as in diamond drills heretofore used, but falls out so soon as the stone is
perforated, thus allowing the drilling machine to be constructed with solid spindles.
For grooving the stone two methods may be employed; firstly, I take square bar
steel and cut or grind the end of it diagonally, as shown at C in Figures 10, 11, 12,
on Sheet A, which represent the tool holder of the planing machine to be herein-
after described. The holder consists of a casting d, having projecting cheeks
between which the tool holder e is fitted, and which moves on a pin at f so as to
relieve itself in the return stroke of the machine. In the lower part of the tool
holder a wedge g is fitted, and is pressed upon by the screw h, and thus grips the

page_text: い
steel cutter o firmly in its seat while it admits of its easy removal when sharpening
is required.
The second method of grooving stones in the planing machine for the purposes of
my Invention consists in the employment of bevilled steel discs or rollers, occupying
the relative position towards each other, shewn in Figures 13 and 14, Sheet A,
where i, i, are the rollers moving on axes j, j, which enter the tool bar h, and are
there retained by the set screws 1, l. The tool shown in these Figures is capable of
working in both directions.
In order that the operation of drilling stones in the manner herein-before
described may be conducted in an economical and expeditious manner I construct
a drilling machine in which two lines of drills extending entirely across the
stone are made to operate at the same time, each drill in its line being capable of
being placed nearer to or further apart, so that the holes made in any stone may be
made equidistant if desired and relatively nearer to or farther from each other in
all directions.
The drilling machine is represented on Sheet B of the annexed Drawings, where
Figure 1 is a front elevation; Figure 2, an end elevation; Figure 3, a plan; and
Figure 4, a vertical section through the centre of the drill heads of the machine.
The main frames A, A, are held together by the cross head B, to which one series of
fixed drills are attached. In front of this cross head is a moveable frame .C of
similar construction, and which carries a second series of drills. The ends of this
framework in dovetailed slides D formed on the inner side of the main frames A,
and is provided with a traversing screw at each end, by means of which the second
series of drills are made to advance or recede from the rolls of drills on the fixed
head. Each series of drills are driven from separate shafts E and F on opposite
sides of the machine. These shafts carry the bevil wheels G, which actuate a series
of countershafts H, which have bevilled wheels at each end, and thus transmit the
motion of the shafts E and F to the two rows of vertical spindles I, as shown. The
feed motion is taken from the shafts E and F by the riggers J to the shafts K, upon
which are fitted worms L, which gear into worm wheels M. In the interior of
these wheels a thread is cut which fits the screw N. These screws are separate from
the spindles, and are kept from turning by the friction of the bands O acting on a
collar, in which is a feather entering a longitudinal slot in the screw.
By this
means any drill may be worked independently of the others by simply throwing up
the handle P, which opens the band O and allows the screw N to turn. The motion
of the screw N being slow permits of its being overtaken by the hand wheel Q,
which withdraws the drill. A quick return motion for the drills is obtained by
reversing the motion of the machine, which causes the V wheels to engage the
screw N by the silent pawl S. The power of the machine overcoming the friction
of the bands O winds the screw N up through the thread in the worm
wheels M.
The reversing motion of the machine is obtained by the well known arrangement
of a plain and cross belt alternately engaging on a fast rigger on an overhead
motion.
The planing machine which I prefer to employ for the purposes of my Invention,
and which is shown in front elevation at Figure 1, Sheet C, of the Drawing
annexed, and in side elevation in the same Sheet, is constructed on the general
principles of machines used for planing metal. The heavy cross slide in which the
tool holders are placed is in part supported by the counterbalance weight below
ground, as shown at K, and which enables the workman to raise the cross slide
with ease.
The stones are placed on the table in a diagonal position, as shewn in Figure 3,
Sheet C, so that two rectangular stones may be placed at the same time. In
grooving stones in such a machine I have found it best to feed the cut by hand,
and not by gearing, as in ordinary planing. Three or four cuts are found most
suitable for deep grooves in Yorkshire flags.

page_text: Having thus described the nature of my said Invention, and the manner of per-
forming the same, I would have it understood that I claim,-
First. The construction of stone pavements with grooves and perforations with or
without inlaid parts, substantially as described and illustrated by the Figures 1, 2,
3, 6, 7, 8, and 9 on Sheet A of the annexed Drawings.
Second. The construction of drills or tools for perforating slabs of stone, sub-
stantially as described and illustrated by the Figures 4 and 5 on Sheet A of
the annexed Drawings.
Third. The construction of machinery to be used in the manufacture or pro-
duction of pavements, substantially as described and illustrated by the Figures 10,
11, 12, 13, 14, and 15 on Sheet A, and the Figures on Sheets B and C of the
annexed Drawings.
In witness whereof, I, the said Thomas Lawrie, have hereunto set my hand
and seal, this Fourth day of July, in the year of our Lord One thousand
eight hundred and seventy-six.
.a
T. LAWRIE (L.S.)