IMPROVEMENTS IN MACHINERY FOR CUTTING AND POLISHING GLASS, GEMS, MARELE, STONES, AND OTHER SIMILAR HARD SUBSTANCES
Year: 1872

page_text: LETTERS PATENT to George Tomlinson Bousfield, of Sutton, in the
County of Surrey, for the Invention of "IMPROVEMENTS IN MACHINERY
FOR CUTTING AND POLISHING GLASS, GEMS, MARELE, STONES, AND OTHER
SIMILAR HARD SUBSTANCES."—A communication from abroad by Charles
PROVISIONAL SPECIFICATION left by the said George Tomlinson
Bousfield at the Office of the Commissioners of Patents, with
his Petition, on the 15th November 1872.
I, GEORGE TOMLINSON BOUSFIELD, of Sutton, in the County of Surrey,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN MACHINERY FOR CUTTING AND POLISHING GLASS, GEMS, MARBLE, STONES, AND
OTHER SIMILAR HARD SUBSTANCES," to be as follows:-
==
The first part of the Invention relates to the manner of holding the
object to be cut firmly enough to prevent vibration, enabling the operator
to detach it from the machine when desired, and to replace it promptly
and easily, or to attach it to another machine for further shaping or
polishing without having to readjust it.

page_text: The second part of the Invention relates to the manner of presenting
the object to the grinding wheel, so that it may have a longitudinal,
lateral, or diagonal motion; also a horizontal, or vertical, circular, or
rotary motion, or a combination of these several motions, so as to pro-
duce automatically and with mathematical precision any desired form,
independently of the skill of the operator.
The third part of the Invention relates to the manner of supporting
and actuating the grinding wheel so that it can have, besides its rotary
motion, a rectilinear movement for producing plane surfaces; also
causing it to revolve on an inclined or vertical axis for certain special
purposes, such as cutting prismatic forms, flutings columns, or producing
any other desired profile.
The fourth part of the Invention relates to the manner of producing
convex or concave curves with mathematical precision as to their form
and relative position on a common axis, and thereby facilitating at the
same time the mounting and setting of optical glasses or other objects.
'
The fifth part of the Invention relates to the manner of securing to
and placing upon the machine cylinders of glass or sections of the same,
so that they can be shaped outside as required, and have their interior
surface turned in one or more perfectly concentric circles, or to have
refracting or reflecting angles cut longitudinally or concentrically with
the outside profile such as are required for different purposes of illumi-
nation, or which may be desired for special useful application in the arts
or for ornamentation.
•
The sixth part of the Invention relates to cutting a "groove around
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Tomlinson Bousfield in the Great Seal
Patent Office on the 15th May 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
TOMLINSON BOUSFIELD, of Sutton, in the County of Surrey, send
greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of November, in the
year of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Tomlinson Bousfield, Her
special licence that I, the said George Tomlinson Bousfield, my execu-
tors, administrators, and assigns, or such others as I, the said George
Tomlinson Bousfield, 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 FOR CUTTING AND POLISHING
GLASS, GEMS, MARBLE, STONES, AND OTHER SIMILAR HARD SUBSTANCES," a com-
munication to me from abroad by Charles William Lewis, of New
York, in the United States of America, upon the condition (amongst
others) that I, the said George Tomlinson Bousfield, my executors or
administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascer-
tain 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 Tomlinson Bousfield, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, that is to say:―
The first part of the Invention relates to the manner of holding the
object to be out firmly enough to prevent vibration, enabling the operator
to detach it from the machine when desired, and to replace it promptly
and easily, or to attach it to another machine for further shaping or
polishing without having to readjust it.
The second part of the Invention relates to the manner of presenting
the object to the grinding wheel, so that it may have a longitudinal,
lateral, or diagonal motion; also a horizontal, or vertical, circular, or
rotary motion, or a combination of these several motions, so as to pro-
duce automatically and with mathematical precision any desired form,
independently of the skill of the operator.

page_text: The third part of the Invention relates to the manner of supporting
and actuating the grinding wheel so that it can have, besides its rotary
motion, a rectilinear movement for producing plane surfaces; also
causing it to revolve on an inclined or vertical axis for certain special
purposes, such as cutting prismatic forms, fluting columns, or producing
any other desired profile.
The fourth part of the Invention relates to the manner of producing
convex or concave curves with mathematical precision as to their form
and relative position on a common axis, and thereby facilitating at the
same time the mounting and setting of optical glasses or other objects.
The fifth part of the Invention relates to the manner of securing to
and placing upon the machine cylinders of glass or sections of the same,
so that they can be shaped outside as required, and have their interior
surface turned in one or more perfectly concentric circles, or to have
refracting or reflecting angles cut longitudinally or concentrically with
the outside profile such as are required for different purposes of illumina-
tion, or which may be desired for special useful application in the arts, or
for ornamentation.
The sixth part of the Invention relates to cutting a groove around
glass discs for adjusting them on the machine, and in the instruments
for which they are intended.
Figure 1 is a plan of the machine as constructed for cutting articles
of comparatively small dimensions where no strictly plane surfaces are
required; Figure 2 is a side elevation of the same; Figure 3 is an end
elevation.
Figure 4 is a back view of the arrangement for causing the grinding
wheel to rise and descend for forming plane surfaces; Figure 5 is a
side view shewing the same, with the grinding wheel stationary, but
revolving in a horizontal position for grooving or fluting; and also if
desired cutting plane surfaces in a longitudinal direction; Figure 6 is
a top view of the attachment for holding and cutting lenses.
Figure 7 is a plan of the attachment for cutting dioptric rings for
light house illumination; Figure 8 is a plan of the same attachment
with ring as arranged when its internal surface is to be cut; Figure 9 is
a section of the above; Figure 10 shews how sections of dioptric rings
are held for cutting the internal surface; Figure 11 shews the same as
held while cutting its external periphery.

page_text: Figure 12 is a plan of the attachment for holding sections of a whole
side of a lantern to be cut with circular and angular ridges on the
principle of the Fresnel dioptric lenses; Figure 13 is a section across the
centre of the same.
Figure 14 is a top view of the cutting or grinding wheel for grinding
the face of lenses or other similar surfaces, also by prolonging the shaft
for shaping the interior of cylinders.
Figure 15 illustrates the manner of holding and shaping a pilaster,
offering the forms most usually required in glass or marble cutting.
A, A, Figure 3, frame firmly fixed to the floor at a convenient height
for the workman, and bearing all the other parts of the machine as well
as the stand a¹, a¹, and upright pillow block a bearing the grinding or
cutting wheel a³ and the pulley a*; B, B, lower sliding frame on which
rests the centre bearing platform. The lower sliding frame can move
on slides or rails, or it may be provided with rollers b, b. It is used
only when an object of large dimensions has to be moved longitudinally
before the cutting wheel. It is provided with proper stops to regulate
the extent of its motion, or to make it stationary when not required;
C, C, centre bearing platform; it can be moved toward or from the grinding
wheel upon flat sides c', c¹², or on antifriction rollers. It bears in the
middle an upright centre pin c³ which serves as the centre of revolution
for the parts of the machine resting upon it. It is provided with wheels
or antifriction rollers c³, c³, disposed on the line of a circle for the turn-
table placed above it. A portion of the circumference bears divisions
of the circle c and sliding stops with set screws attached to them,
and so disposed on the segment of the circumference as to regulate the
extent of the semicircular motion of the object to be cut when the turn-
table is moved by hand. The reciprocal circular motion can also be
produced by a pulley drum c and adjustable crank c'.
The rectilinear motion of the centre bearing platform or frame is
regulated by guide bars c³ provided with rings o° and stops, and it can'
be made automatic when effected toward the cutting wheel by a rope o
and weight c". The centre of rotation of the turntable regulates the
kind of curve to be produced; if the object to be cut be placed between
the centre and the cutting wheel the curve is convex; if it be placed
beyond the centre the curve is concave.
The distance horizontally
between the centre and the object forms the radius of the curve D, D,

page_text: turntable; it is a circular frame provided with a flat ring with two
flanges forming a groove d³, d, which runs upon the antifriction
rollers c³, c³, of the centre bearing platform. It bears an oblong fixed
frame, two sides of which serve as slides d³, d³, for the adjusting
frame d³, d³, to rest on, upon which it is adjusted by means of a long
regulating screw d', d, running in a female screw attached to the
bearing carriage. It is provided with an index d', which travels over
the divided segment, and strikes against the stops to regulate the extent
of its circular motion. The adjusting frame d³ is provided with four
bearing wheels or antifriction rollers do, do, upon which slide longi- 1
tudinally the bearing carriage E; E, bearing carriage; it is a square
or oblong frame; the lower surface of two of its sides e², e¹, is provided
with a flange, and it slides upon rollers d³, d'; its upper surface is
provided with two projecting, partly circular and concentric, seg-
ments e², e³, with a set screw e³; these segments are thus arranged to 1
receive between them corresponding segments attached to the bearing
frame e', et, and allow this frame to be adjusted in any parallel or
diagonal position with respect to the body of the machine.
•
By this arrangement an object can be cut in a conical form wherever
desired by being placed diagonally with respect to the cutting wheel, 2
and the bearing carriage being moved longitudinally in front of the
wheel, as shewn at e³, e³, Figure 1. The bearing frame e* has two
uprights e, e, and a rest e³ to receive and secure the holder F and the
object to be shaped. F, F, holders, their use is to hold the objects
to be cut and to present them in rapid succession to the cutting wheel 2
for producing each of the different lines of the desired profile in a
perfectly uniform manner, and with mathematical accuracy. Each
holder is composed of a strong wrought or cast-iron bar with two
arms f¹, f¹, projecting at right angles; through the ends of these bars
are tapped two screw holes, which receive the screwed centre pins f³, 3
which hold the object to be cut firmly by pressing against two discs
lined with lead, india-rubber, or other soft substance when necessary.
The screwed pins bear upon the forked end of the uprights es, es. One
of the discs f³ acts as a dividing plate by having holes f* drilled in a
circle around the centre at such distances and in such number as it is 3
desired to have sides cut into the object to be shaped. The disc f³ is
held in position by the arm ƒ provided with a projecting pin fitting
exactly in the dividing holes; a spring f keeps it in place. One of the

page_text: centre pins f is provided with a crank, which can be turned by hand
for cutting circular forms on light objects. For heavy articles, a pulley
moved by a belt can be substituted for the crank G centring chuck for
holding lenses, Figure 6. The end of the three jaws g¹ are made very
angular, so as to fit a groove previously cut in the edge of a disc of
glass. This groove can serve after the lens is finished to mount and
adjust it into the instrument for which it is intended. The chuck being
placed upon the bearing frame, as shewn in the Drawing, Figure 6, the
focus of the desired radius is brought over the centre of the turntable
where it is fastened. Then by vibrating the turntable to the right and
left, and bringing forward the bearing carriage to the proper degree of
penetration to secure the grinding of every part of the lens surface,
turning the crank g' at the same time, a curve is produced which must
evidently be a section of the circumference of a sphere, with a radius
regulated by the centre of rotation, and also an axis exactly at a right
angle with the groove around the lens. It is easily perceived that a
corresponding convex curve can be out on the opposite side of the same
disc by reversing the glass on the chuck.
"
A concave curve for producing a perfect meniscus with a true axis is
obtained by reversing the lens upon the chuck, and bringing the bearing
carriage so that the focus of the radius is brought to a point back of the
outside edge of the cutting wheel equally distant from the centre of the
turn-table, less the thickness of the glass as it was in front of the wheel
when cutting the convex side.
The advantages offered by the groove, above referred to, cut in the
edge of the disc of glass to be shaped into a lens are manifold; by that
means the disc is easily adjusted and held in the centering chuck, and
a true and common axis secured for the two sides of the lens. In the
methods now in general use the disc is held by cement, and when one
side is shaped it is reversed to be cemented again, no strictly accurate
This
guide being used for securing the relative position of the curves.
requires on the part of the operator a degree of practical dexterity which
many years of labor can only secure. The uncertainty of the operation, and
the time necessary for accomplishing it sufficiently explain the high price
which such articles command. A few minutes of labor in our machine
are sufficient to produce a perfectly shaped lens. The groove around the
edge serves also to facilitate the work of the optician who can thus easily
mount a lens in a telescope or camera obscura with the utmost certainty

page_text: of having the two focuses in a straight line and in the centre of the tube
to which they are to be attached.
The form of wheel we adopt for grinding the face of lenses or other
optical instruments, as better calculated to preserve the integrity of the
curves of a large radius, is the one shewn at Figure 14. It will be per-
'ceived that the wheel a³ has a straight periphery, a³ and a bevil a*, which
can be made broader than the periphery of an ordinary wheel without
increasing its size. It is keyed to the end of a shaft a', and can be made
to penetrate the inside of a ring or cylinder by merely prolonging the
end of the shaft to which the wheel is fixed. By having the periphery |
of the wheel angular, or otherwise shaped, corresponding forms can be
cut on the internal surface of cylinders, such as lanterns or other
appliances used for illumination. The shaft runs in two pillar blocks, a³
fixed to a pivoting platform aº, bolted in its centre to the frame a,
which can be attached to the main pillar block table a¹¹, supported by
the stand a¹, a¹, Figures 1, 2, and 3. This arrangement allows the wheel
to be placed in any diagonal position, as seen in Figure 14.
H, H, Figures 7, 8, 9, 10, and 11 is the chuck used for cutting rings
in one or more pieces, when they have to be cut and polished on all
their surfaces. It is composed of a main plate h¹ screwed upon a ?
shaft h³, which holds it upon the carrying frame, and is furnished with
a crank or a pulley to cause it to revolve. On the periphery of the
plate are screwed adjustable jaws h³ for holding the ring in position by-
In the interior is a
pressing upon its exterior and upper surfaces.
movable polygonal disc h* with exterior projections, which may be fixed 2
or adjustable if desired. This disc is centred by means of the short
shaft ³, and is compelled to turn with the main plate h¹ by means of
the pin hº.
The operation of this chuck is as follows:-' The ring of glass is placed
upon the main plate and centred as near as possible by the jaws h³ and
the polygonal disc h*. A cement composed of plaster or other
equivalent substance is run upon the disc which it surrounds, and thus
binds the glass ring to it. When the cement is set the jaws are
removed and the exterior surface of the ring is shaped, receiving the
required curve from the combined reciprocal motion of the turntable :
and the revolution of the main plate on its own axis.
When that part
of the work is finished the disc and ring are inverted, then the under

page_text: or flat surface of the ring is exposed and presented to the cutting
wheel which grinds upon it a perfectly plane surface exactly at a right
angle with the axis of the ring itself. When this part is finished the
jaws are put on and properly tightened, the interior polygonal disc and
cement are removed and the interior periphery of the ring is shaped by
exposing it to the grinding action of a wheel smaller than its own
interior diameter, and fixed upon the end of a projecting shaft.
The ring, when made of sections with space allowed for the mounting,
as required for large linghthouse dioptric or catadioptric glasses, is fixed,
as seen in Figures 10 and 11, the spaces / being filled by the cement
above referred to. Small adjustable clamps may also be placed in the
spaces h³ to render the cementing stronger. It may be found preferable
to commence the operation by grinding the flat part of the ring
first.
When it is desired to work a whole segment of a compound lens for
lighthouse, signal, ship, wharf, or large street lights, the rocking bearer,
shewn in Figures 12 and 13, is used.
I, I, rocking bearer:-It is composed of two arms *, *, projecting
from shafts *, **, each working in two pillar blocks fixed to the bearing
frame e'. The arms are provided with straight centre slots ** in which
the holder is adjusted; are two slots (one of which is not shewn in
the Drawing) in which are fixed two adjustable stiffening bars 3ª firmly
screwed upon the arms to secure their parallelism. The end of the
rocking shaft is provided with a crank for moving the bearer and
glass segment. A counterpoise or putting the whole arrangement
in equilibrium, facilitates the rocking of the glass segment, and
requires but a slight exertion on the part of the operator; is the
glass segment to be shaped.
The operation is performed as follows:-The glass is firmly secured
upon the holder so that its curved part may be as concentric as possible
with the rocking shafts. The carriage is fixed upon the turntable, so
that the focal radius of the spherical curve corresponds with the centre
of horizontal revolution of the turntable. The face of the cutting
wheel used is diagonal to form the perpendicular edge of the rings. The
centre lens is cut by the ordinary wheel with straight periphery.
This form is obtained by moving the turntable to the right and left
alternately. The extent of the motion is regulated by the stops c³ on

page_text: the divided circle c*, Figure 1. When the centre lens is formed the
angular wheel, with its cutting angle to the right, is used to form the
rings, after which it is inverted to cut the rings. The depth of
the rings or penetration is adjusted by stops regulating the rectilinear
motion of the centre bearing frame C. To form the interior of the seg-
ment, and give it either a cylindrical shape or cutting rings corresponding
with the outside ones, it is merely required to reverse the glass segment
without removing it from its holder, so that the concave side is offered
to the cutting wheel, whose diameter must then be smaller than the
radius of the glass cylinder. The wheel has to work then between the
rocking shafts. It can be easily understood how these three motions,
first, the vertical rocking; second, the horizontal vibratory motion; and,
third, the alternate rectilinear motion can be executed simultaneously
by an operator without any great exertion of mind or body, and are so
regulated as to secure the most perfect uniformity for any number of
pieces. When the pieces to be shaped are to have some plane surfaces
or diagonal cuttings the mode of supporting the cutting wheel, shown
in Figures 4 and 5, or some equivalent method, must be adopted. J,
Figures 4 and 5, is the frame adjusted to the pillar block table a¹; j¹is
a sliding frame moving in grooves indicated by the dotted lines . The
up-and-down motion is caused by the adjustable crank ³, the pulley
wheel, and the connecting rod j. The box attached to the sliding
frame bears the adjustable but fixed shaft j, which supports at one end
the driving wheel and the pulley or drum j³, both of which revolve
upon it, and together. To the other end of the shaft is fixed the
frame bearing the cutting wheel a³, to the shaft of which the mitre
wheel is keyed. This receives its motion from the mitre wheel " and
the pinion . It will be easily understood by an examination of the
Drawing that by this arrangement the cutting wheel can be placed in a
vertical position or diagonally, as shown by the dotted lines, Figure 4, or
horizontally, as shown in Figure 5. In every position it receives its
rotary motion without altering any part of the driving gearing.
It must be observed here that the scale used in the Drawing is
intended merely for a machine of medium size, calculated to shape all
the articles required for ordinary household use. The machine intended
for gems or small optical glasses would of course be smaller, and those
intended for columns, obelisks, or other parts of monuments would of
course have to be of larger dimensions. Aprons of metal or of india-

page_text: rubber, as seen hanging from e¹ Figure 2, are placed wherever necessary
to keep the sand used in cutting from falling upon any of the slides or
antifriction rollers. These aprons are very important, as from the
nature of the work performed, where sand is constantly used it is very
difficult or almost impossible to keep the machine at work without this
protection. The machine being constructed substantially as described,
its operation is as follows:-Supposing for example that a pillar, as
shown in Figure 15, of glass,. marble, serpentine, or other substance of
that nature is to be cut, a piece of material of the proper size is prepared
of the required length, and truly squared at both ends. If of glass it
might be moulded or blown of the required dimensions in a wooden or
other mould. It is adjusted in the holder f¹, and if a great number of
the same kind are required an equal number of holders are prepared so
as to save further readjustment. It is placed then upon the forked end
of the uprights attached to the carrying frame e', and secured in that
position by cross pins or otherwise, the object to be shaped being made
to revolve on itself with the two discs, one of which the dividing wheel f³
is turned by the crank or a pulley driven by power when the object is
of large dimensions. The carrying frame is adjusted upon the bearing
carriage so that the longitudinal motion of the object will be parallel
with the axis of the pillar to be cut. The centre bearing frame is
brought in position so that its centre be opposite the cutting wheel.
The rectilinear motion is adjusted by means of the stops so that the
penetration of the wheel will reach to the straight line No. 1. The
dividing disc is made fast by the arm f³, and its pin falling in one of
the holes which can divide the circle into four equal parts if the base
No. 1 is to be square, or into six if it be desired to have it hexagonal.
The bearing carriage is moved to the left so that the right edge of the
cutting wheel can come into line with the left side of the dividing
disc f. A stop is fixed so that the carriage E cannot move further to
the left, and another stop is fixed to the right so that the carriage
cannot move in that direction further than the length of line No. 1.
The cutting wheel is set in motion so that it will revolve, and also move
up-and-down as before explained. The operator moves the carriage to
the right, and one side of the base is soon cut perfectly flat and
parallel with the axis of the pillar. The next side is made by turning
the object so that the pin ƒ³ will fall in the proper dividing hole, and the
operation is repeated as before described until the base is finished. The
part No. 8 can then be made by moving the bearing carriage to the

page_text: right; and regulating its motion so as to cut the part 8 of the pillar.
The part 2 is made by a longitudinal motion of the carriage, a vibratory
motion of the turn table, a penetration of the centre bearing frame, and
an alternate, rectilinear, and vertical motion of the cutting wheel frame.
This is made in two distinct operations. The pillar is divided and cut
first into four equal semi-conical and curved parts; then the corners are
cut by the same motions but with less penetration. Part 3 is cut by a
cutting wheel with a rounded periphery, a rotary motion of the pillar,
and a regulated penetration of the centre-bearing platform. Part 4 is
made by fixing the carrying frame in a slightly diagonal position upon
the bearing carriage so that the longitudinal line of that part which is
desired to be conical will run parallel with the line of motion of the
carriage. The dividing disc is left free to turn by withdrawing the
stopping pin f³. The crank is turned while the carriage is moved right
and left, and the centre bearing frame moved forward until it has
reached the stops which regulate the size of that conical portion 4 of the
pillar. When a truncated cone of the required length and breadth has
been formed, the cutting wheel with periphery of proper shape is placed
horizontally and its frame fixed so that the wheel shall be opposite the
axis of the pillar. The dividing disc is made stationary by the pin f';
the degree of depth and the length of the flutings are regulated by the
stops; and the bearing carriage is moved right and left longitudinally
until one ridge is cut; then the pin f' is withdrawn and the pillar
turned so as to bring the next proper dividing hole in position for the
pin to fix it there. The second fluting is cut as was the first, and the
operation is repeated until that part of the pillar is finished; the part 5
is cut as was part 3. The part 6 is cut by a vibratory motion of the
turn table, the stop toward the right on the divided segment of the circle
being fixed further to the right of the centre than the other to the left
of it, the pillar being rotated by means of the crank. In that way the
inclined curve 6 is produced; while this is being done the grinding
wheel rises and lowers. Part 7 is cut as 3 and 5, the wheel also working
up and down, and the dividing disc adjusted to produce four sides.
When the object has been shaped as described it is taken to the
smoothing and polishing machine,. and subjected to the usual treatment
required for finishing, smoothing, and polishing it. The processes of
smoothing and polishing being carried on in the same manner as the
cutting, the forms, curves, and sharp edges are more perfectly preserved
than can possibly be done when the objects are held by hand.

page_text: By what precedes, it can be seen that nearly all forms can be obtained
with this machine in combination with a cutting or grinding wheel, flat
or diamond shaped surfaces, circular grooves, rings, mouldings, fillets,
prisms, flutes, diagonal curves, in a word all shapes found in decanters,
vases, pedestals, cups, goblets, pyramids, tablets, &c.; also profiles of
glass or marble plates for inlaid work can be shaped in the most regular
manner.
This system offers another advantage which cannot be possibly
accomplished by the present method of cutting glass by hand, viz., the
facility offered by it of producing exact duplicates of articles manufactured
previously and which may be broken.
The manufacturer, by keeping a register of the different objects, an
outline with the degrees of curves, radiuses, length, and penetration of
the different surfaces, can always adjust his machine so as to obtain an
exact copy of the required article. It is obvious that by the ordinary
system of glass working such a result is utterly impossible.
What I claim and desire to secure by Letters Patent is,―
1. The holder F, in combination with the grinding wheel used in
cutting glass, gems, marble, &c., and also in combination with the
polishing wheels used in our machine, the whole constructed and operated
substantially and for the purpose as herein-before set forth.
2. The machine for presenting to the grinding wheel the object to be
shaped, consisting of the lower sliding frame B, the centre bearing plat-
form C, the turn table D, the bearing carriage E, and the apron or
aprons for protecting the working parts against the action of the gritty
substances used in cutting and polishing stone, the whole constructed
and operated substantially, and for the purpose as herein-before set forth.
3. The grinding wheel as in combination with the sliding frame j³, the
adjustable shaft jo, and the adjustable frame jo, bearing the adjustable
wheel a³, the whole constructed and operated substantially and for the
purpose as herein-before set forth.
4. The grinding wheel a' in combination with the pivoting platform aº,
the whole constructed and operating substantially and for the purpose
as herein-before set forth.
5. The chuck G, for holding lenses in combination with the adjustable
bearing frame eª and a grinding wheel.

page_text: 6. The chuck H, for holding rings, sections of rings, or cylinders, in
combination with a grinding wheel, the whole constructed and operated
substantially and for the purpose as herein-before set forth.
7. The rocking bearer I, for holding sections of cylinders, or of spheres,
and presenting their outside and inside surfaces to the grinding wheel, the b
whole constructed and operated substantially and for the purpose as
herein-before set forth.
8. The groove cut in the periphery of discs for lenses or other objects
requiring perfect parallelism of opposite sides, the whole constructed and
operated substantially and for the purpose as herein-before set forth.
In witness whereof, I, the said George Tomlinson Bousfield, have
hereunto set my hand and seal, this Eighth day of May, in
year of our Lord One thousand eight hundred and seventy-three.
1