IMPROVEMENTS IN MACHINERY TO BE USED FOR GRINDING AND POLISHING GUN BARRELS, SWORDS, MATCHETS, BAYONETS, SCYTHES, FIRE IRONS, AND OTHER ARTICLES SIMILAR IN TRANSVERSE SECTION TO ANY OF THOSE ABOVE NAMED
Year: 1856

page_text: LETTERS PATENT to Thomas Lawrence, of Birmingham, in the County
of Warwick, Manufacturer, for the Invention of "IMPROVEMENTS IN
MACHINERY TO BE USED FOR GRINDING AND POLISHING GUN BARRELS, SWORDS,
MATCHETS, BAYONETS, SCYTHES, FIRE IRONS, AND OTHER ARTICLES SIMILAR IN
TRANSVERSE SECTION TO ANY OF THOSE ABOVE NAMED."
Sealed the 11th November 1856, and dated the 21st May 1856.
PROVISIONAL SPECIFICATION left by the said Thomas Lawrence at the
Office of the Commissioners of Patents, with his Petition. on the:
21st May 1856.
I, THOMAS LAWRENCE, of Birmingham, in the County of Warwick, Manu-
facturer, do hereby declare the nature of the said Invention for "IMPROVEMENTS"
IN MACHINERY TO BE USED FOR GRINDING AND POLISHING GUN BARRELS, SWORDS,.
MATCHETS, BAYONETS, SCYTHES, FIRE IRONS, AND OTHER ARTICLES SIMILAR IN
TRANSVERSE SECTION TO ANY OF THOSE ABOVE NAMED," to be as follows:-
This Invention has for its object the grinding or polishing of all the sides, or
the entire surface of articles of the description above named, at one and the same-
time. The machine by which this is effected consists of two or more standards
or holsters, with slides similar to those of a direct-acting steam engine. The

page_text: standards are secured to a bed plate, and between them are hung vertically in
the motion blocks of the slides shafts or spindles, carrying stones or com-
position pulleys, by a series or combination of links and levers, having their
centre of motion in two traverse shafts, hung at different heights in the frames;
the bearings of the pulley.spindles are moveable, and can be brought into
united action by the power of a master lever; this lever is governed by a
balance weight, thus rendering. it capable of the most accurate adjustment, so
as to bring the grinding or polishing pulleys into a state of equipoise suspen-
sion, in which state the elevating or depressing the master lever has the effect
of advancing or receding the peripheries of the stones or pulleys to or from a
common centre. The machine is also, furnished with a compound, self-acting
feeding apparatus, combining lateral rotary and osciliatory motion. As an
example of the action of the machine, I will instance the grinding of a bayonet
blade, on which I use the convex peripheries of three stones or pulleys, which,
being caused to advance or recede at will from their common centre, present
between them the figure of an equilateral triangle, with a concavity in each
side, exactly similar to the cross section of a bayonet blade. When two stones
or pulleys only are used, it will be sufficient if the top stone or pulley be
capable of rising or lowering; but in operating upon articles of more than two
sides, the moveable bearings of two of the shafts or spindles have a range of
from one to ninety degrees, in other words, from a horizontal to a vertical
position, and thus they form the angles for any shape required to be ground or
polished. Articles of a cylindrical section may be ground or polished by two
stones or pulleys having concave grooves on their peripheries. In constructing
the composition pulleys I have named, I propose to cast the composition on to
the pulley or rollers by means of chills, of a corresponding section to the form
required for the grinding or polishing pulleys.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Lawrence in the Great Seal Patent Office on
the 21st November 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
LAWRENCE, of Birmingham, in the County of-Warwick, Manufacturer, send
greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her Letters
Patent, bearing date the Twenty-first day of May, in the year of our Lord-One

page_text: thousand eight hundred and fifty-six, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Thomas Lawrence, Her special licence that I, the said Thomas Lawrence, my
executors, administrators, and assigns, or such others as I, the said Thomas
Lawrence, 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 TO BE
USED FOR GRINDING AND POLISHING GUN BARRELS, SWORDS, MATCHETS, BAYONETS,
SCYTHES, FIRE IRONS, AND OTHER ARTICLES SIMILAR IN TRANSVERSE SECTION TO ANY
OF THOSE ABOVE NAMED," upon the condition (amongst others) that I, the said
Thomas Lawrence, by an instrument in writing under my hand and seal, 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 Lawrence, do hereby declare the
nature of my said Invention, and in what manner the same is to be per;
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon, that is to say:-
The object of my Invention has been the production of improved machinery
or apparatus to be used in the operations of grinding and polishing gun barrels,
swords, matchets, bayonets, scythes, fire irons, and other articles similar in
transverse section to any of those I have named, and by which improved
machinery or apparatus I am enabled to grind, flat, or polish, not only the
plain surfaces of the above-named articles, but also to grind out of the solid
metal, upon certain of the articles named, the furrows, ribs, or grooves which
are required to be formed thereon, or to grind the said furrows or ribs or
grooves after the same shall have been rolled or forged in such articles; for.
instance, on matchets, out of the solid metal, after the said matchets have
undergone the process of hardening; and I am also enabled to grind or polish
such furrows; ribs, or grooves in matchets, swords, and bayonets after they
have been rolled or forged therein.
In order that this my Invention may be more clearly understood, I have
hereunto appended Drawings of my improved machinery or apparatus as
adapted to the purpose of grinding, flatting, and grooving matchets,
2

page_text: Figure 1 is a side elevation of the machine. Figure 2, a front or end
elevation; and Figure 3, a plan, as seen from above.
. I shall now proceed, with the assistance of these Drawings, to describe the
working of the machine. (A) is the main driving band, passing from a
common driving shaft, from which the power is derived, over the fast pulley (B),
hung on the spindle (C). A loose pulley (D) is also hung on the same spindle,
on to which loose pulley (D) the driving band (A) can be readily shifted, by
means of the lever rod and finger (E), whenever it may be found requisite to
throw the machine out of gear. A second band (F) passes round the drum (G),
and on to the pulley (E), and a third band (I) passes over a corresponding
drum (K), and on to a similar pulley (L). (M, M,) are a pair of frames or
standards carrying the spindles or shafts (N, N'), upon which the grinding
wheels or pulleys (0, O',) are hung; the upper one of these (0) being
mounted on the same shaft or spindle which carries the driving pulley (H),
and the lower one (O') on the same shaft with 'the corresponding pulley (L)..
The lower of these grinding pulleys (0¹) revolves on fixed bearings secured, to
the standards, but the upper one (0) has moveable bearings, and is capable of
being raised at will to admit of the introduction of the article to be ground
between the peripheries of the grinding wheels, which operation of raising the
upper wheel is effected by means of the treadle (P), connected by the jointed
lever (Q) to (a master lever R); two similarly jointed arms or levers (S, S),
one on each side of the machine, and which are secured at their lower ends to
the shaft or spindle upon which the upper grinding wheel is hung, have a
common fulcrum, with the master lever (R) at the point (T), consequently, on
the depression of the treadle (P) by the foot, the axis of the upper grinding
wheel is raised, its state of equipoise suspension being maintained by a Salter's
spring balance (U), adjusted to any degree of pressure required, and which is
attached at one end to a bracket on one of the standards, and at the other
end to the master lever (R). The compensating spring (V) on the other
end of the master lever, and which spring. may be of any desired .power, will
give the necessary pressure of the upper grinding wheel upon the article
under operation to ensure the sufficient amount of grip or bite; the distance
between the peripheries of the upper and lower grinding wheels is maintained
and regulated by two screws (W, W), one in each standard, which bear upon
the spindle or shaft of the upper grinding wheel, and being adjusted to any
required position, prevent the possibility of contact between the two grinding

page_text: wheels, thus their horizontal position is governed. But it is also necessary to
provide that the grinding wheels may be set in precisely the same vertical
plane; to effect this, I cut screws upon the shaft of the lower grinding wheel,
upon which two nuts (X, X,) are fitted, by which I am enabled to adjust the
lower grinding wheel accurately to the vertical plane of the upper one. To.
ensure the maintenance of the proper position of the matchet whilst being
ground between the two surfaces or peripheries of the grinding wheels, the
small friction rollers (Y, Y,) are provided, which act as guide rollers, and
against which the back of the matchet may be pressed whilst under operation..
The small band and pulley (Z) is provided for the purpose of equalizing the
friction, and of counteracting the tendency which the larger band (F) would
have to drag the axis of the upper grinding wheel to one side, thus causing
more friction on one side than on the other; and a regulating motion being
required for this counteracting pulley and band (Z), it is provided by causing
the carriage upon which the pulley is mounted to slide in a groove on its bed,
motion being given by a screw, it can consequently be regulated to any degree
of tension, increasing or decreasing the friction, as circumstances may demand.
The grinding wheels or pulleys (O, O',) travel at very high velocities, and both
in the same direction; they are formed either of grindstone, such as is com-
monly used for this purpose, or of composition cast upon metal pulleys.
The material I find the best suited for my purpose, and to which I give the
preference, is a composition patented by David Fisher, of London, on the
Seventh day of July, in the year of our Lord One thousand eight hundred
and fifty-six, under the title of a composition for coating metal plates or wheels
used for grinding, sharpening, or polishing, and which composition is easily
rendered subservient to the double purposes of grinding and polishing by using
different degrees of fineness.
The grinding wheels or pulleys are formed into the shape I require by.
casting a sufficient quantity of the composition in a heated state round a metal
pulley placed in a chill or iron mould, the internal periphery of which chill or
mould is shaped into the form required to produce on the periphery of the
casting the ribs, or furrows, or forms I may require on my grinding pulley ;
thus, for grinding and flatting matchets I use composition pulleys whose.
peripheries are of the form shewn in Figure 4 of the Drawings.
For producing the grooves or furrows in such matchets, I must have one,
two, or more projecting ribs or flanges on the peripheries of my grinding
pulleys, whilst for grinding the sides or edges of parallel-sided articles I form,
a collar or flange on opposite sides of each pulley or stone, as seen in Figure 5,
:

page_text: because, in the case of grindstones or pulleys formed with both the collars upon
one stone only, 'they would soon become inoperative, by reason of the wearing
away of the collars or flanges; but by having one collar on each stone, and
on opposite sides of each stone respectively, instead of two collars on one stone
and none on the other, I can readily compensate for the diminution of such
collars by wear; by readjusting these stones laterally, and so as to keep them
accurately fitting into each other.
I have stated that the grinding wheels or pulley's described are required to
travel at very high velocities, and it is also necessary to keep them wet. I
find that the ordinary mode of effecting this, viz, by causing water to drop
upon the stones, is utterly useless, as the centrifugal force caused by such
velocity prevents the water from taking any effect; I therefore insert a pit of
water obtained from a high level between the peripheries of the pulleys or
grinding wheels, and keep a bundle of "hurds," which consists of the coarse
part of flax, hemp, or tow, or a sponge, or some such substance, in immediate
contact with the peripheries of the pulleys whilst they are in motion. The pit
of water plays into the hurds or sponge, which acts as an absorbent, retaining
the superfluous water, and by pressing against the revolving pulleys keeping
them constantly wet.
I will now briefly state the modification that would be necessary in the con-
struction of the machine, as shewn in the Drawings, to render it applicable to
the purpose of what is generally known in the trade as "cross grinding." It
is only requisite that the standards of the machine should be so constructed as
to leave the lower part of the upper stone and the upper part of the lower
one completely exposed at the sides, which will admit of the introduction of
the articles at the side as well as at the front of the machine.
Thus far I have described my Invention in its application to the purposes
of grinding and polishing flat articles, such as matchets and swords, and which
it will be understood are thus operated upon on both of their sides or surfaces,
and in certain cases upon both their edges also simultaneously.
In grinding or polishing the blades of bayonets or other articles; triangular
in section, I employ three grinding stones or pulleys, having peripheries of a
convex section, and so mounted that I can at will cause them to recede or
advance from their common centre, presenting between the peripheries of such
three stones or pulleys at their point of nearest contact the figure of an equi-
lateral triangle, having a concavit in each side exactly corresponding to the
cross section of a bayonet blade. For all articles having more than two sides,
the moveable bearings of two of the shafts or spindles. carrying the stones or

page_text: pulleys must have a range of from one to ninety degrees, in other words, from
a horizontal to a vertical position, thus, the stones or 'pulleys may be hung
and regulated to any angle, according to the shape of the article required. to
be ground or polished..
Articles of a cylindrical form in section may be ground or polished by
employing either two grinding wheels or pulleys, having on their peripheries
semicircular grooves, or three or more pulleys or wheels having on their
peripheries segmental grooves.
I would remark, that the operations herein detailed of grinding and polishing
the articles named, are by my Invention carried out with equal facility after
the hardening of the article to be operated upon has taken place; and that, for
the purpose of polishing the furrows in matchets, I sometimes employ, in lieu
of the composition pulleys, laps or pulleys formed of metal, a mixture of lead
and tin, and whilst in use I keep the peripheries of such metal laps or
pulleys supplied with emery, composition powder, or other suitable cutting
material.
Having thus described the nature of my said Invention, and the manner
in which the same is practically to be carried into effect, I wish it to be clearly
understood that I do not confine myself to these precise details, as the same may
admit of variation without departing from the spirit of my Invention; but that
which I claim, and desire to have secured to me by the herein-before in part
recited Letters Patent, is,-
Firstly, the arrangement and combination of the several parts constituting
machinery or apparatus to be employed for the purposes of grinding and polish-
ing gun barrels, swords, matchets, bayonets, scythes, fire-irons, and other
parallel-sided or tapered articles, similar in transverse section to any of those
above named, as herein described.
Secondly, I claim the grinding and polishing of any of the above-named
articles by the employment of two or more plain or grooved grinding wheels
or pulleys, or metal laps, as herein mentioned, such wheels, pulleys, or laps
rotating all in the same direction.
Thirdly, I claim the grinding or polishing of the edges or backs of flat
articles, such as files, by the employment of grinding wheels or pulleys, having
each a projecting collar or flange on opposite sides, as seen in Figure 5 of the
Drawings, and by the position of which flanges I am enabled to adjust the
said grinding wheels or pulleys, so as to compensate for the gradual reduction
of such collars or flanges by wear.
Fourthly, I claim the application of grinding wheels or pulleys formed of

page_text: composition cast upon a metal base, as a substitute for the ordinary grindstone,
to the purposes of grinding and polishing the several articles enumerated in
the title of my Patent, as herein described.
And, lastly, I claim the use of two or more lead laps or pulleys for the
purpose of grinding and polishing the flutes or furrows in matchets after the
the said matchets have been hardened, as herein more fully set forth and
specified.
In witness whereof, I, the said Thomas Lawrence, have hereunto set my
hand and seal, this Nineteenth day of November, in the year of our
Lord One thousand eight hundred and fifty-six.
THOMAS LAWRENCE. (L.S.)