CERTAIN IMPROVEMENTS IN METALLIC MILLS FOR GRINDING COFFEE, CORN, DRUGS, PAINTS, AND VARIOUS OTHER MATERIALS
Year: 1831

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
SELDEN, of Liverpool, in the County Palatine of Lancaster, Merchant, send
greeting..
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Eleventh day of August, in the second year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
David Selden, His special licence, sole privilege and authority, that I, the
said David Selden, my executors, administrators, and assigns, or such others
as I, the said David Selden, my executors, administrators, or assigns, should
at any time agree with, and no others, from time to time and at all times
during the term of years therein mentioued, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, an Invention of "CERTAIN IMPROVEMENTS IN METALLIC MILLS FOR
GRINDING COFFEE, CORN, DRUGS, PAINTS, AND VARIOUS OTHER MATERIALS;" in which
said Letters Patent is contained a proviso that I, the said David Selden, shall
cause a particular description of the nature of the said Invention, and in what
manner the same is to be performed, to be inrolled in His Majesty's High
Court of Chancery within six calendar months next and immediately after the
date of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear..
NOW KNOW YE, that in compliance with the said proviso, I, the said
David Selden, do hereby declare that the nature of the said Invention, and in

page_text: what manner the same is to be performed, is particularly described and ascer-
tained by the following description thereof (reference being had to the Draw:
ings hereunto annexed, and to the figures and letters marked thereon), that is
to say:-
These improvements in metallic mills consist in combining the following
parts and pieces-First, I provide an iron plate represented in the Drawings
at Fig. 1, which plate, intended to constitute the back of the mill, has a
circular part a, a, a, with a flat surface. From the side of this circular part
an ear b, b, extends, with holes through it, for the purpose of screwing or
otherwise securing it to a post or part of the building where the mill is to
be used, and a dovetail-formed piece c, c, extends from the top of the circle
which is to constitute one side of the hopper, and below is a small recess d,
to form the back part of the shute. The thickness of this plate and its sec
tional form are represented at Fig. 2, which is a transverse section of the
complete mill when all its parts are put together. In the centre of the circular
plate there is a square cavity e, intended to hold a washer or piece of metal
to act against the end of the central axle of the runner. Fig. 3 represents
the runner f, f, which is formed nearly as the segment of a sphere or of an
extremely obtuse cone, with the teeth or indentations on its surface, having a
shaft or axle g, extending from its centre, as shewn in Fig. 2. The circular
edge of this runner, at the back part, bears against the plate a, a, a, and the
back end of its axle against the washer before mentioned in the recesse
the front end of the axle being elongated for the purpose of having a crank
handle or rigger attached to it by which the mill might be driven. Fig. 4 is
an inside view of the cap h, h, h, which answers to the bed of the mill. The
internal part of this cap is formed conically, but not quite so obtuse as the
surface of the runner, in order that a wider space may be left toward the apex
of the cone, for the articles in grinding to be first broken, and then gradually
reduced to fine powder as they approach the outer edges of the cones.
surface of the runner f, and also of the cap h, are cut into teeth or indenta-
tions in oblique directions, commencing from the axle, and extending to the
edges. Five or more diagonal teeth i, i, i, i, i, according to the size of the mill,
are cut deep near the centre, in order to receive the articles to be 'ground, and
diminished toward the edges to a fine score. These teeth are placed with
their sharp angles toward the work, in order to carry out the material while
grinding toward the edge, as in the ordinary millstones. The angular spaces
between these large teeth toward the outer parts of the cones are cut in the
same manner as shewn at k, k, k, into angular teeth; and on the periphery
projecting pieces at small distances apart as clearers,
of the runner there are
The

page_text: to carry round the material when ground to the delivering spout. The runner,
placed upon the plate, as shewn at Fig. 5, is kept in its proper situation by
the cap which is fixed over it, as seen in the section, Fig. 2, and also in the
external view of the mill, Fig. 6, the axle passing through the aperture in
the centre. The cap is then made fast to the plate by screws or rivets passed
through the lugs or pieces at l, l. A piece at bottom of the cap completes the
form of the delivering spout at m, and the piece n, which constitutes the other
part of the hopper, is attached by screws or rivits in like manner. The
runner being thus mounted is turned upon its axle by the crank, and moves
freely round within the cap, the space between the two being regulated by the
screw o at the back of the washer, and thus the mill is suited to grind to any
degree of fineness that may be desired. The material to be ground is now
introduced into the hopper, from whence it descends through the aperture p,
in the cap, between the two conical surfaces, and becomes broken or pulverised
as the runner revolves, the material being received into the mill near the
apex of the cones, where the teeth are course and deep, for the purpose of
being first broken, and is driven out towards the edges of the cones, where
the teeth become gradually finer, by which it becomes sufficiently reduced or
pulverised before it is delivered by the clearers to the spout.
That which I claim as new is the above construction of the cones, and the
manner of commencing the grinding at the centre where the teeth are course,
and finishing at the periphery where they are fine, upon the same principle
of the ordinary corn-mill stones, and the making of all the principal parts of
cast iron or of wrought iron or of stamped plate iron, if that should be found
practicable, and the peculiar arrangement of the parts, and manner of cutting
the teeth to points, described before: The hopper described as cast in two
parts may (if necessary) be made whole, which will reduce the number of
parts or pieces, and render the ears upon them and the rivets unnecessary.
These mills may be made of any size for all purposes to which they may be
applicable, and placed in frames or screwed to any secure rest; and when
any article is to be reduced to an impalpable powder, or if paint or drugs are
to be ground in oil or water, the edge of the cones, from one quarter to half
an inch inwards, may be left plain, to rub against each other, serving the same
purpose as the common paint stone and muller.
In witness whereof, I, the said David Selden, have hereunto set my
hand and seal, this Ninth day of February, in the year of our Lord
One thousand eight hundred and thirty-two.
DAVID (L.S.) SELDEN.

page_text: AND BE IT REMEMBERED, that on the Ninth day of -February, in the
second year of the reign of His Majesty King William the Fourth, the said
David Selden came before our said Lord the King in His Chancery, and
acknowledged the Instrument aforesaid, and all and every thing therein
contained and specified, in form above written. And also the Instrument
aforesaid was stamped according to the tenor of the Statute made in the
fifty-fifth year of the reign of His late Majesty King George the Third.
Inrolled the Eleventh day of February, One thousand eight hundred and
thirty-two.