A NEW OR IMPROVED MANUFACTURE OF CROWN AND SHEET GLASS."
Year: 1857

page_text: LETTERS PATENT to William Perks, junior, of Birmingham, in the
County of Warwick, Manufacturer, for the Invention of "A NEW OR
IMPROVED MANUFACTURE OF CROWN AND SHEET GLASS."
PROVISIONAL SPECIFICATION left by the said William Perks at the
Office of the Commissioners of Patents, with his Petition, on the
4th April 1857.
I, WILLIAM PERKS, junior, of Birmingham, in the County of Warwick,
Manufacturer, do hereby declare the nature of the said Invention for "A NEW
OR IMPROVED MANUFACTURE OF CROWN AND SHEET GLASS," to be as follows:-
My said Invention consists in treating crown and other sheet glass by a
polishing process, whereby the smoked or dull appearance common to the
surface of crown glass is removed, or the said glass polished. The said smoked
appearance is commonly called "sulphur," and renders the glass unfitted for
uses where brilliancy of surface is required.
By my Invention the film of sulphur is removed, and great brilliancy imparted
to the surface of the glass. In carrying my Invention into effect, I mount
a horizontal disc or circular table upon a vertical axis, to which motion is given
by any convenient driving power. The said table is covered with felt or other
soft material, and the glass to be treated is placed upon the said table, the said
glass being prevented from moving with the table by stops, against which
the glass bears at suitable points. Upon the felt is spread, with a brush or
otherwise, a mixture of peroxide of iron and water, or other polishing material.
The glass is loaded with weights, and by the motion of the disc or table the
polishing of the glass and the removal of the sulphur is effected.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Perks in the Great Seal Patent Office on the
2nd October 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, J, WILLIAM
PERKS, junior, of Birmingham, in the County of Warwick, Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of April, in the year of our Lord One
thousand eight hundred and fifty-seven, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Perks, Her special licence that I, the said William Perks, my
executors, administrators, and assigns, or such others as I, the said William
Perks, 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 "A NEW OR IMPROVED
MANUFACTURE OF CROWN AND SHEET GLASS," upon the condition (amongst others)
that I, the said William Perks, my executors or administrators, by an instru-
ment 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 William Perks, do hereby declare
the nature of the 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 thereof, that is to say:-
My said Invention consists in treating crown and other sheet glass by the
polishing process herein-after described, and illustrated in the accompanying
Drawing, by which said polishing process the smoked or dull appearance
common to the surface of crown glass is removed, or the said glass polished.
The said smoked appearance is commonly called "sulphur," and renders
the glass unfitted for uses where brilliancy of surface is required.
By my Invention the film of sulphur is removed, and great brilliancy
imparted to the surface of the glass.
Figure 1 of the accompanying Drawing represents in elevation (partly in
section) the machinery by which I carry my Invention into effect, and

page_text: Figure 2 represents a plan of the same. a is a horizontal dise or circular
table mounted upon the vertical shaft b. Motion is communicated from any
convenient source of power to the shaft b and table a, and the said motion
arrested through the fast and loose pullies c, d. The said table a is covered
with felt a', Figure 1, or other soft flexible material may be substituted in
place of the said felt. The pieces of glass e, e, to be operated upon are placed
upon the table a, the said pieces of glass e, e, being prevented from moving
with the table by stops f and f', attached respectively to the frame h and the
cross bar i; the pieces of glass may, however, be held in any other convenient
manner. k, k, are wedge-shaped pieces of plate glass or other material, which
are supported by the frame h and the stops f. Upon the felt a¹ is spread
with a brush or otherwise a mixture of peroxide of iron and water, or other
polishing material. The pieces of glass k, k, resting upon the felt, effect the
uniform distribution of the polishing material over the table. The pieces of
glass e, e, are loaded with weights g, g, whereby the said pieces of glass e, e, are
pressed with the required force on the table a. By the motion of the table a
the polishing of the fixed pieces of glass e, e, and the removal of the sulphur
therefrom is effected.
My Invention is applicable to crown and other sheet glass where high
polish or brilliancy of surface is required.
Having now described the nature of my said Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit
myself to the precise details herein described and represented, as the same
may be varied without departing from the nature of my Invention; but I
claim as my Invention, the new or improved manufacture of crown and
sheet glass, herein-before described, and illustrated in the accompanying
Drawing, that is to say, polishing crown and sheet glass by pressing the said
glass upon a horizontal rotating disc or table, the upper surface of which is
covered with a polishing mixture, the sheets of glass being held stationary by
the use of suitable stops.
In witness whereof, I, the said William Perks, have hereunto set my
hand and seal, this First day of October, in the year of our Lord One
thousand eight hundred and fifty-seven.
WILLIAM PERKS, JUN. (L.S.)
Witness,
GEORGE SHAW.