In- PROVEMENTS IN APPARATUS FOR LEVELLING, FURROWING, AND DRESSING MILLSTONES
Year: 1869

page_text: LETTERS PATENT to Thomas Mortlock, of No. 5, Singleton Street,
Hoxton, in the County of Middlesex, for the Invention of "In-
PROVEMENTS IN APPARATUS FOR LEVELLING, FURROWING, AND DRESSING
MILLSTONES."
Scaled the 6th July 1869, and dated the 14th January 1869.
PROVISIONAL SPECIFICATION left by the said Thomas Mortlock at
the Office of the Commissioners of Patents, with his Petition, on
the 14th January 1869.
I, THOMAS MORTLOCK, of No. 5, Singleton Street, Hoxton, in the
County of Middlesex, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS FOR LEVELLING, FURROWING, AND DRESSING
MILLSTONES," to be as follows:-
This Invention has for its object improvements in apparatus for
levelling, furrowing, and dressing millstones. For these purposes I
employ a metal frame truly planed and faced on the under side, which
when the apparatus is in use rests on the stone to be operated on, and is
there kept in place by its own weight. On the frame a carriage is
mounted, and it is capable of sliding along it in guides from end to end,

page_text: a inution which is given to it by manual labour. The carriage has upon
it a tool holder capable of being traversed across the carriage by a screw.
In the tool holder is fixed a tool; it may be a diamond or steel point or
cutter, and as the carriage is moved along the frame the tool traces lines
upon the face of the stone. The point or tool is set down to the depth
required by a screw, and with the tool holder it is moved a minute
distance across the carriage before each forward traverse of the carriage;
this motion is given by the sciew of the carriage operated on by a self-
acting ratchet and pawl. Thus it will be seen that at each action the
cutter forms a minute and perfectly true groove on the stone, either on
the face or in the furrow, as the case may be; and these lines being
repeated very closely together and parallel the one to the other the
required level and roughened face is given to the stone, and the furrows
are made and kept of the proper depth. When one quarter or part of
the stone is complete the frame is shifted on to the next quarter or part
which is similarly operated on, and so the operation goes on until the
work on the stone is complete.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Mortlock in the Great Seal Patent Office
on the 14th July 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
MORTLOCK, of No. 5, Singleton Street, Hoxton, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of January, in the
year of our Lord One thousand eight hundred and sixty-nine, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Thomas Mortlock, Her special
licence that I, the said Thomas Mortlock, my executors, administrators,
and assigns, or such others as I, the said Thomas Mortlock, 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

page_text: 1-
APPARATUS FOR LEVELLING, FURROWING, AND DRESSING MILLSTONES," upon the
condition (amongst others) that I, the said Thomas Mortlock, my exe-
cutors or administrators, 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 Thomas Mortlock, 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 :-
This Invention has for its for its object improvements in apparatus
for levelling, furrowing, and dressing millstones. For this "purpose I
employ a metal frame truly planed and faced on the under side, which
when the apparatus is in use rests on the stone to be operated on, and is
there kept in place by its own weight. On the frame a carriage is
mounted, and it is capable of sliding along it on guides from end to end,
a motion which is given to it by manual labor. The carriage has upon
it a tool holder capable of being traversed across the carriage by a screw.
In the tool holder is fixed a tool; it may be a diamond or steel point or
cutter, and as the carriage is moved along the frame the tool traces lines
upon the face of the stone. The point or tool is set down to the depth
required by a screw, and with the tool holder it is moved a minute
distance across the carriage before each forward traverse of the carriage;
this motion is given by the screw of the carriage operated on by a self-
acting ratchet and pawl. Thus it will be seen that at each action the
cutter forms a minute and perfectly true groove on the stone, either 'on
the face or in the furrow, as the case may be; and these lines being
repeated very closely together and parallel the one to the other the
required level and roughened face is given to the stone, and the furrows.
are made and kept of the proper depth. When one quarter or part of
the stone is complete the frame is shifted on to the next quarter or part
which is similarly operated on, and so the operation goes on until 'the
work on the stone is complete.
And in order that my said Invention may be most fully understood
and readily carried into effect I will proceed to describe the. Drawings

page_text: DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plan, Figure 2 is a side view, Figure 3 is a tranverse
section, and Figure 4 is an end view of the apparatus; it consists of a
frame formed of two side bars a, a, truly planed on their under sides and
tied together by the cross bars a', a'. On this frame a carriage bis
mounted; it is capable of sliding from end to end of the frame on guide
ribs on either side. The carriage rests on these ribs, and is held securely
upon them by guide strips a' on its under side which are fixed to the
carriage by screws, and can be adjusted to compensate for any wear
which may take place in the ribs. c is a screw carried in bearings on
the carriage; it works in a nut or female screw formed in the tool
carrier; d, d, is a socket mounted on the tool carrier, so as to be able to
slide vertically through it without rotating; into this socket a diamond
set in a suitable holder or other cutter is fixed, and the socket together
with the cutter can be raised or lowered by turning the hand wheel d²,
which operates by means of a screw, as is clearly shown at Figure 3;
b' is a handle on the carriage b by which the carriage can be moved
along the frame a; e is a clamp capable of being fixed on the side of the
frame a at any point in its length by means of a clamping screw e'; it
has a stud or axis projecting from it on which a T-shaped pawl or
catch fis mounted so as to be able to turn freely for a short distance in
one direction, but it is stopped in the other direction by its T head
resting against a projection on the clamp e; c' is a star wheel fixed on
the screw c, and when the carriage is moved to and fro on the frame the
pawl or catch comes against the teeth of the star wheel. When the
carriage approaches the pawl or catch in the direction in which the pawl
or catch is able to yield the star wheel passes it, and the screw is not
turned, but on the return of the carriage the pawl or catch being unable
to yield the star wheel and screw are turned. The wheel is rotated
either one tooth or two according as the pawl or catch is set. In order
that the screw may not shift from the positions into which it is turned
by the pawl or catch it has lock nuts at its end, which can be set to bear
against the end cheek of the carriage so as to oppose any desired amount
of resistance to the motion of the screw. There is a clamp e with a
pawl or catch fixed near each end of the frame, so that the screw may
receive a movement carrying the cutting tool sideways the distance
required between the lines after each traverse of the carriage. When it
is desired to reverse the direction in which the screw is rotated it is done

page_text: by taking the T-formed pawls or catches off their studs and turning
them over.
In working the apparatus supposing, in the first place, that the stone
requires to be levilled, the frame is placed on the stone to be operated
upon, or it may be on small blocks resting upon it, and the tool is then
set so as to cut on the elevations whilst it misses the hollows. The
carriage is worked to and fro by hand until the tool holder has traversed
over a width sufficient for one of the side bars a of the frame to stand
upon. Then the tool is set deeper and the pawls or catches fare turned
over, and the work recommences and is continued until the tool is
brought back to the place from which it started, and so the work goes on
until the tool cuts evenly on every part of the surface which is being
operated on. Then in a similar way another similar portion of the stono
is reduced truly to the same plane as the first, and it is arranged that the
distance between the portions so levelled shall be such that the two sido
bars a of the frame can stand on them simultaneously, then the inter-
vening parts of the stone are without difficulty reduced to the same
plane, and so the work goes on until the whole stone is levelled. The
furrows are then cut by placing the frame on the stone parallel to the
furrow it is desired to cut, bringing the tool to the furrow and traversing
it, as already described, until it is worked down to the depth required.
When one furrow is worked the next is similarly cut. The soveral
furrows, which are parallel the one to the other, are cut without shifting
the frame, but the frame is shifted in passing from one set of furrows to
another.
It will be necessary to use right and left handed tools in order to work
into the angles of the furrows.
In dressing the stone the apparatus is used to score the parts between
the furrows with fine parallel lines; this may be done as the tool is
passed from furrow to furrow. a*, a", are slots in the frame, into which
bolts may in some cases be fixed to serve as stops to bear on the
periphery of the stone should the apparatus be found to have any
tendency to shift on the stone when in use.
What I claim is, the arranging apparatus for levelling, furrowing, and
dressing millstones substantially as above described, such apparatus
consisting of a frame so made as to stand on the stone to be operated on
and supporting a carriage with a tool holder and tool, such carriage

page_text: being capable of being slidden by hand labor to and fro on the frame.
whilst the tool holder is gradually traversed across the carriage.
In witness whereof, I, the said Thomas Mortlock, have hereunto
set my hand and seal, this Seventh day of July, in the year of
: our Lord One thousand eight hundred and sixty-nine.