IMPROVEMENTS IN APPARATUS TO BE USED IN THE MANU- FACTURE OF MILLSTONES AND IN THE WORKING OF HARD STONES IN GENERAL
Year: 1868

page_text: LETTERS PATENT to George Davies, of No. 1, Serle Street, Lincoln's
Inn, in the County of Middlesex, and No. 87, St. Vincent Street,
in the City of Glasgow, Civil Engineer and Patent Agent, for the
Invention of "IMPROVEMENTS IN APPARATUS TO BE USED IN THE MANU-
FACTURE OF MILLSTONES AND IN THE WORKING OF HARD STONES IN
GENERAL." A communication from abroad by Samuel Golay, of
Paris, Machinist.
Sealed the 5th September 1868, and dated the 21st March 1868.
PROVISIONAL SPECIFICATION left by the said George Davies at
the Office of the Commissioners of Patents, with his Petition, on
the 21st March 1868.
I, GEORGE DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the
County of Middlesex, and No. 87, St. Vincent Street, in the City of
Glasgow, Civil Engineer and Patent Agent, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN APPARATUS TO BE
USED IN THE MANUFACTURE OF MILLSTONES AND IN THE WORKING OF HARD
STONES IN GENERAL," (a communication to me from abroad by Samuel
Golay, of Paris, Machinist, to be as follows:-
Letters Patent were granted to me (on behalf of the said Samuel
Golay) dated April 30th, A.D. 1867, No. 1245, for "Improvements in

page_text: Cutting and Dressing Millstones and in Apparatus to be Employed
for such Purpose," which were based on the employment of the
diamond attacking the stone in place of the hammer or pick hitherto
in use.
The machine described in the Specification of the said Letters Patent
is specially designed for millers for the repairing and keeping up the
dressing of the millstones. In fact the cutting and dressing which
are therein mentioned and which the machine is capable of executing
are confined (as will be evident) to the restoration or maintaining of
the dressing which had been originally produced or given to the
stone by the manufacturer. The machine therein described would
not be strong enough and would be too light to attack and level a
rough surface since it rests by its own weight which should suffice
for the resistance which the work demands, and besides the fact of
its. resting simply by its own weight on three feet requires a surface
previously levelled, otherwise the machine would only make an uneven
surface corresponding with the different heights of the points on
which the three feet would be successively placed.
The object of the above statement is to prevent any confusion
between the former machine intended for millers and that which forms
the subject of the present application and which the Inventor offers
to millstone manufacturers for working the rough stone, not only
the millstone when put together, but also the pieces of which it is
composed before putting them together. It is therefore to apparatus
for manufacturing millstones that the present Invention is confined.
The employment of this system, according to whether it is applied
to the levelling or dressing of the united stone or for the dressing of
the isola.ed pieces intended to compose the same, naturally involves
some modification in the arrangement of the apparatus, but I will
here describe the general arrangement of the machine as adapted for
levelling or dressing the stones after binding together.
The apparatus comprises, firstly, a strong frame which supports
the millstone by means of three regulating screws.
This framing is
placed above a pit or well which contains part of the mechanism,
amongst which is a vertical shaft capable of turning on a pivot and
corresponding with the centre of the millstone. The top of this shaft
turns in a casting fixed to the frame above mentioned. At the upper
end of this shaft is fixed by a key or pin a boss or slide carrier

page_text: which turns with the shaft. To this boss is bolted a slide which is
horizontal, that is to say, at right angles to the shaft when the
plane surface of the millstone is to be dressed, but which is inclined
at will when it is desired to work the central conical part of the stone
by which the grain enters between the working surfaces. On the
slide works a carriage which may be moved to and from the centre by
means of a screw provided at its extremity with a star or dividing
wheel. The slide carries a frame or tool carrier furnished with a
suitable number of pointed screws upon which the tools or cutters
revolve. The tools or cutters are formed as described in the Specifi-
cation above alluded to with a. diamond tooth turning with great
rapidity and attacking the stone by so many small shocks. The tool
carrier is mounted on pivots and is regulated or inclined at will by
means of screws. The boss is surmounted by a column, at the top
of which is pivoted a vertical shaft. The latter communicates (by a
pair of friction cones or bevil wheels) rotary movement to a drum
or cylinder round which pass the endless bands or cords which drive
the revolving cutters or tools. At each revolution of the central shaft
the star, or dividing wheel comes against a fixed finger, which moves
it one tooth and thus causes the tool carrier to be moved in a very
slight degree, either nearer to or further from the centre according
to whether it is preferred to work from the circumference towards the
eye of the stone, or vice versa.
The whole apparatus is driven by suitable gearing from a main
driving shaft..
SPECIFICATION in pursuance of the conditions of the Letters Patent;.
filed by the said George Davies in the Great Seal Patent Office:
on the 21st September 1868..
TO ALL TO WHOM THESE PRESENTS' SHALL COME, I, GEORGE
0 DAVIES,. of No. 1, Serle Street, Lincoln's Inn, in the County of
Middlesex, and No. 87, St. Vincent Street, in the City of Glasgow,..
Civil Engineer and Patent Agent, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of March,. in the

page_text: year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-first year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Davies, Her special licence
that I, the said George Davies, my executors, administrators, and
assigns, or such others as I, the said George Davies, executors,
administrators, or 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 Island, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN APPARATUS TO BE USED IN THE MANUFACTURE OF MILLSTONES AND IN THE
WORKING OF HARD STONES IN GENERAL," communication to me from
abroad by Samuel Golay, of Paris, Machinist,) upon the condition
(amongst others) that I, the said George Davies, my executors 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 George Davies, 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 in writing, reference being had to
the accompanying Sheet of Drawings, that is to say :-
Letters Patent were granted to me (on behalf of the said Samuel
Golay), dated April the Thirtieth, in the year of our Lord One thousand
eight hundred and sixty-seven, No. 1245, for "Improvements in Cutting
and Dressing Millstones and in Apparatus to be Employed for such
Purpose," which were based on the employmeut of the diamond
attacking the stone in place of the hammer or pick hitherto in use.
The machine described in the Specification of the said Letters Patent
is specially designed for millers for the repairing and keeping up the
dressing of the millstones. In fact the cutting and dressing which are
therein mentioned, and which the machine is capable of executing, are
confined (as will be evident) to the restoration or maintaining of the
dressing which had been originally produced or given to the stone by the
manufacturer. The machine therein described would not be strong

page_text: enough and would be too light to attack and level a rough surface since
it rests by its own weight which should suffice for the resistance which
the work demands, and besides the fact of its resting simply by its own
weight on three feet requires a surface previously levelled, otherwise the
machine would only make an uneven surface corresponding with the
different heights of the points on which the three feet would be
successively placed.
The object of the above statement is to prevent any confusion between
the former machine intended for millers, and that which forms the
subject of the present application, and which the Inventor offers to mill-
stone manufacturers for working the rough stone, not only the millstone
when put together but also the pieces of which it is composed before
putting them together. It is therefore to apparatus for manufacturing
millstones that the present Invention is confined. The employment
of this system according to whether it is applied to the levelling
or dressing of the united stone or for the dressing of the isolated
pieces intended to compose the same naturally involves some
modification in the arrangement of the apparatus, but I will here
describe the general arrangement of the machine as adapted for levelling
or dressing the stones after binding together.
Such being the nature and object of the said Invention for " Improve-
ments in Apparatus to be used in the Manufacture of Millstones and in
the Working of Hard Stones in general," I will now proceed to describe
more in detail the manner in which the same is to be or may be
performed or carried into practical effect; and in order that the same
may be distinctly understood I have annexed hereunto a Sheet of
Drawings illustrative thereof, and have marked the same with figures
and letters of reference corresponding with those in the following
explanation thereof, that is to say:-
Figure 1 is a side elevation of the apparatus shown partly in section;
Figure 2 is a front view of same; Figure 3 is a plan view in which the
drum is removed in order to show the carriage; the driving gear is not
shown; Figure 4 is a plan view of the framing and well or pit with the
flooring removed.
The apparatus comprises, firstly, a strong frame A which supports the
millstone B by means of three regulating screws C; this framing is
placed above a pit or well which contains a part of the mechanism,
amongst which is a vertical shaft D capable of turning on a pivot and

page_text: corresponding with the centre of the millstone. The top of this shaft
turns in a casting N fixed to the frame A above mentioned. At the
upper end of this shaft is fixed by a key or pin fa boss or slide carrier E
which turns with the shaft; to this boss is screwed by bolts d and ba
slide G which is horizontal, that is to say, at right angles to the shaft
when the plane surface of the millstone is to be dressed, but which is
inclined at will when it is desired to work the central conical part of the
stone by which the grain enters between the working, surfaces. On the
slide G works a carriage H which may be moved to or from the centre
by means of a screw L provided at its extremity with a star or dividing
wheel M. The carriage H supports a frame or tool carrier J furnished
with a suitable number of pointed screws K upon which the tools. or
cutters revolve.
The tools or cutters are formed as described in the Specification
above alluded to with a diamond tooth turning with great rapidity
and attacking the stone by so many small shocks: The tool carrier J
is mounted on pivots and is regulated or inclined at will by means of
screws d. The boss E is surmounted by a column Q, at the top of which
is pivotted a vertical shaft Q¹; the latter communicates (by a pair of
friction cones or bevel wheels P) rotary movement to a drum or
cylinder O, round which pass the endless bands or cords which drive the
revolving cutters or tools K. The whole apparatus is driven by
suitable gearing from a main driving shaft S, which receives its motion
from the pulley X. The shaft S puts the upper part of the machine in
motion by means of the shaft Q and grooved pulleys R and R', and
drives the lower part by means of a pulley T. This pulley turns the
shaft of an endless screw or worm T which gears with a worm wheel on
the intermediate shaft U, which thus receives a slow rotary movement.
The shaft U in its turn transmits this motion to the main shaft D by the
pair of wheels V and V. The result is that the boss E. and the whole
system G, H, J, K, O, turns slowly producing an effect analogous to
that of a circular beam compass. The height of the whole apparatus and
consequently the depth to which the tools attack the stone may be
regulated, the shaft D being pivotted upon a regulating, footstep similar to
that of the turning millstones.
The employment and operation of the machine is as follows:-When
it is intended to use the machine for levelling a stone the first operation
is to dismount the shaft Q and the boss E which is removed, taking

page_text: with it all its appurtenances, the column, the slide, the carriage, the
tool carrier, and the drum O which puts them in motion. The end
of the shaft D alone projects beyond the frame A and screws C. The
millstone is then placed on these screws, which are provided with plates,
the shaft D passing into the central eye of the stone. The latter is
then levelled by means of the screws C, and the boss E with all it
carries is replaced as well as the shaft Q. The stone is casily centered
by turning round the carriage, which acts as a beam compass. This
having been done several tools are then mounted in the tool carrier J,
care being taken that the one nearest to the centre (if working
from the circumference towards the centre) shall be higher than the
second, the latter higher than the third, and so on, in order that they
shall attack the stone gradually. The driving shaft S is then put in
motion and communicates a very slow rotary movement to the shaft
D.and consequently to the carriage and a very rapid movement to
the tools. It follows that the latter driven with a very rapid rotation
moves in a circular direction over the upper surface of the stone,
attacking and levelling it by removing all the asperities and pro-
jecting portions. Each time that the carriage has performed an entire
revolution the star wheel M comes against a fixed finger Y, which
causes it to turn one tooth and move the carriage slightly towards
the centre. The latter makes a second round, meets the finger again,
and so on till the carriage arrives at the centre of the stone and the
cut is finished. The following cut may be made by raising the point Y¹
higher; the finger Y then meeting the star wheel above instead of below
the centre turns the screw L in the opposite direction and moves the
carriage from the centre towards the circumference. The height of the
apparatus and consequently the extent to which the diamond attacks
the stone at a time is regulated by the screwed wheel Z and the
regulating screw and lever Z', by means of which the apparatus is
lowered slightly at each cut.
The above described is a simple and practical arrangement of the
apparatus and its application. It is evident, however, that is capable
of great modification in its arrangement and application without altering
the principle. For example, the circular or beam compass movement
may be replaced by a rectilinear motion, and this would perhaps answer
better for dressing the detached pieces of which the millstone is com-
posed. Whatever may be the arrangement it always comprises a
certain number of diamonds or hard stones mounted and attacking

page_text: the stone by repeated shocks, which latter is realized in the most
practical manner by a rapid rotation. The diamond cutters are mounted
in a tool carrier and a carriage, which allows of their gradually and
regularly attacking the surface of the stone to be dressed either by
mcans of a curvilinear or a rectilinear movement.
Having now described the nature and object of the said Invention
for "
Improvements in Apparatus to be used in the Manufacture of
Millstones and in the Working of Hard Stones in general," together
with the manner in which the same is to be or may be performed or
carried into practical effect, I would remark in conclusion that I claim
as the Invention communicated to me by the aforesaid Samuel Golay,―
Firstly. The employment and application to the manufacture of
millstones of the diamond or hard stone, tools or cutters acting in the
manner described and previously applied by him only to the dressing
or renovating of millstones.
Secondly. The application of the above described system of apparatus
to the cutting or surfacing of the detached pieces intended to form
the millstone when bound together or of the millstone itself after it
has been bound together.
Thirdly. The construction and employment for this purpose of a
machine possessing the different functions or movements above described,
whether such machine is constructed precisely as shown in the annexed
Drawings and above described or is a mere modification or imitation
thereof constructed and operating in substantially the same or a similar
manner.
In witness whereof, I, the said George Davies, have hereunto
set my hand and seal, this Twenty-first day of September,
in the year of our Lord One thousand eight hundred and sixty-
eight.