IMPROVEMENTS IN MILL- STONES OR GRINDERS, and IN THE MANUFACTURE THEREOF.
Year: 1872

page_text: LETTERS PATENT to George Albion Tate, of West Hartlepool, in the
County of Durham, for the Invention of "IMPROVEMENTS IN MILL-
STONES OR GRINDERS, and IN THE MANUFACTURE THEREOF.'
"
Sealed the 6th December 1872, and dated the 13th June 1872.
PROVISIONAL SPECIFICATION left by the said George Albion Tate
at the Office of the Commissioners of Patents, with his Petition,
on the 13th June 1872.
I, GEORGE ALBION TATE, of West Hartlepool, in the County of
Durham, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN MILLSTONES OR GRINDERS, AND IN THE MANUFACTURE THEREOF,”
to be as follows:-
The improvements consist in the substitution of metal in lieu of a
portion of stone, constructed in such manner as to form a compound
grinder of metal and stone.
The improvements may be carried into effect by making the rim of
the grinder of a ring of suitable stone in one or more pieces, and the
ring may have a plain or grinding surface or otherwise, and be con-

page_text: structed of any convenient thickness and width. Within the ring is
inserted a moveable and adjustable metal grinding plate or plates
furnished on their outer surface with suitable grooves, ribs, or raised
surfaces moveable or otherwise, for the purposes of grinding. Attached
to the metal grinding plate by suitable distance and adjusting bolts is
a cover plate or plates, so adjusted with reference to the grinding plate
as to keep and support it distanced from the cover plate in such a
manner that the respective surfaces of the plates may be flush or nearly
so with the respective upper and lower surfaces of the stone ring or
rim, and when desired by means of the distance or other suitable bolts
the grinding plate may be as it or the stone ring wears away adjusted*
and kept flush or nearly so with the grinding or other surface of the
stone rim.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Albion Tate in the Great Seal Patent
Office on the 7th December 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
ALBION TATE, of West Hartlepool, in the County of Durham, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Hei
Letters Patent, bearing date the Thirteenth day of June, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Albion Tate, Her special
licence that I, the said George Albion Tate, my executors, adminis-
trators, and assigns, or such others as I, the said George Albion Tate,
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
Ircland, the Channel Islands, and Isle of Man, an Invention for "Ix-
PROVEMENTS IN MILLSTONES OR GRINDERS, AND IN THE MANUFACTURE THEREOF,"

page_text: upon the condition (amongst others) that I, the said George Albion
Tate, 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 Albion Tate, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement:-
The improvements consist in the substitution of metal in lieu of a
portion of stone, constructed in such manner as to form a compound
grinder of metal and stone.
The improvements may be carried into effect by making the rim of
the grinder of a ring of suitable stone in one or more pieces, and the
ring may have a plain or grinding surface or otherwise, and be con-
structed of any convenient thickness and width. Within the ring is
inserted a moveable and adjustable metal grinding plate or plates
furnished on their outer surface with suitable grooves, ribs, or raised
surfaces moveable or otherwise, for the purposes of grinding. Attached
to the metal grinding plate by suitable distance and adjusting bolts is
a cover plate or plates so adjusted with reference to the grinding plate
as to keep and support it distanced from the cover plate in such a
manner that the respective surfaces of the plates may be flush or nearly
so with the respective upper and lower surfaces of the stone ring or
rim, and when desired by means of the distance or other suitable bolts
the grinding plate may be as it or the stone ring wears away adjusted
and kept flush or nearly so with the grinding or other surface of the
stone rim.
For convenience a suitable eye or centre hole may be formed in the
grinding and the other metal plate, and convenient lugs may be left on
the plates for their insertion into the stone ring.
The accompanying Drawings will serve to illustrate a convenient
mode of carrying the improvements into effect, in which Figure 1 shews
section of upper and lower grinder; Figure 2, plan of bottom grinder
with half of face plate off; Figure 3, plan of back plate for bottom

page_text: grinder Figure 4, half section of back plate for bottom grinder;
Figure 5, plan of iron plate, which supports four adjusting screws
secured to burrs of upper grinder; Figure 6, half section of the last-
mentioned plate; Figure 7, plan of horn or pillar plate for upper
grinder Figure 8, half section of No. 7; Figure 9, plan of top grinder
with half of face plate off.
In the foregoing Figures A represents French burr or other material
suitable for grinding purposes; B, backing; C, iron plate, secured with
four bolts to burrs of top grinder and tapped to receive four adjusting
screws; D, four adjusting screws for drawing face plate back as burrs 1
wear away; E, horn or pillow plate for carrying centre bar and face
plate; F, face plate with works secured by four bolts to pillar plate:
G, face plate for bottom grinder; H, three pillar bolts with adjusting
washers. As the burr wears away a washer is taken off each pillar bolt
and put under the bolt head; then by screwing bolts up again the face 1
plate is brought back to the required distance, or the same result may
be obtained by using packing. I, plate secured to back of grinder by
four bolts suitably let into the burr.
In witness whereof, I, the said George Albion Tate, have hereunto
set my hand and seal, this Thirtieth day of November, in the year 2