IMPROVEMENTS IN POLISHING AND FLATTENING METAL PLATES
Year: 1854

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of Glasgow, North Britain, Gentleman,
for the Invention of "IMPROVEMENTS IN POLISHING AND FLATTENING METAL
PLATES." A communication from Henry Beaud, of Paris, in the Empire
of France, Manufacturer.
Sealed the 20th October 1854, and dated the 27th April 1854.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
27th April 1854.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN POLISHING AND FLATTENING
METAL PLATES" to be as follows:-
This Invention relates more especially to the flattening and polishing of
daguerreotype plates, although the same apparatus is applicable also to the
flattening of metal plates for other purposes, and consists in the substitution of
a rolling or pressing action for the hammering process at present employed, by
which means the flattening of the plates is effected in a much shorter time and
with greater regularity than can be obtained by the old process. The plates to
be flattened are first polished on a flat table or bed, fitted with sliding clamps,
to retain it secure during the polishing process. The polished plate or a pair
of them are then freed entirely from dust, and placed back to back between
a pair of polished steel pressing plates or blocks, the surfaces of which are well
freed from dust, and the whole is enclosed in an opening frame fitted with a

page_text: hinge, and tightened by ineans of a screw pin. The necessary pressure is
obtained from a pair of pressing rollers or other pressing mechanism. When
perfectly flattened, the finishing polish is effected by manual labor, or by
suitable polishing mechanism.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on the
27th October 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
and of Glasgow, North Britain, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of April, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I, the
said John Henry Johnson, my executors, administrators; or 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 "IMPROVE-
MENTS IN POLISHING AND FLATTENING METAL PLATES," a communication from
Henry Beaud, of Paris, in the Empire of France, Manufacturer, upon
the condition (amongst others) that I, the said John Henry Johnson,
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 John Henry Johnson, 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, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say:.
The said Invention relates more especially to the flattening or polishing of,
daguerreotype plates, although the same apparatus is applicable also to the
flattening of metal plates for other purposes, and consists in the substitution of

page_text: a rolling or pressing action for the hammering process at present employed, by
which means the flattening of the plates is effected in a much shorter time
and with greater regularity than can be obtained by the .old process. The
plates to be flattened are first polished on a flat table or bed, fitted with sliding
clamps, to retain it secure during the polishing process. The polished plate or a
pair of them are then freed entirely from dust, and placed back to back between
a pair of polished steel pressing plates or blocks, the surfaces of which are well
freed from dust, & the whole is enclosed in a frame fitted with a hinge, and
tightened by means of a screw pin. The necessary pressure is obtained from a
pair of pressing rollers or other pressing mechanism. When perfectly flattened;
the finishing polish is effected by rubbing with the hand, or by suitable polishing
mechanism. In order to arrive at the best result, it is advisable to employ a
metal plate of the finest grain. This plate is then heated, scoured, and any
porosities filled up with the greatest care, after which it is polished. For
this
5 purpose a table is employed, represented in Figures 1 and 2 of the accom-.
panying Sheet of Drawings, which table may be of any size, according to the
size of plate to be polished. This table A is carried by an ordinary table or
support, and has fixed to it an internally projecting ledge a; it is also fitted
with a moveable side b, situated opposite to the ledge a. The moveable side is
pushed forward by means of a screw c, and is guided by two slotted guide
plates d, one of which is fitted on to each end of the table A. The plate to be
polished is laid upon this table, and retained firmly thereon by being nipped
between the sides a and b. In this position it is well polished by the aid of
polishing pads of skin, felt, velvet, &c., and rotten stone or other suitable impal-
pable powder mixed with distilled water, diluted alcohol, or acidulated water,
care being at the same time taken to remove all greasy particles, so that the
surface of the plate may assume a fine dark appearance. The same care should
be taken in polishing the pressing surfaces of the squeezing plates or blocks B
& B', represented at Figures 3, 4, 5, 6, and 7 of the Drawings. The whole
having been thus prepared, one of the blocks B is laid upon the support C, and
the daguerreotype plate or a pair of them are then laid upon the block with
their backs together, the polished faces having been previously well cleaned
from dust; the plate or plates are then covered over with the second block B',
the face of which has been previously polished, and the block itself laid in
readiness for use upon a cushion of skin E, Figure 5, with the polished face
downwards. The face of the block is then rubbed over the cushion E before
it is removed, by taking hold of the handles ff. These handles are only
necessary when large heavy blocks are employed. The two blocks B, B', with
the plate between them, are then enclosed in the hinged frame D, which is

page_text: supported upon the two projecting legs e, e, Figures 3 and 4; the frame is then
closed and screwed up tight by the screw 9, (Figures 3 and 7,) which has a
square bead formed upon it to receive a handle. The whole is then subjected
to the pressing action of a pair of rollers H, H', Figure 4, through which the
plates are passed two or three times, according to the size of the plate, and the
pressure required to strengthen or flatten it. This part of the operation con-
stitutes the base of the Invention. It admits of the obtainment of greater
regularity, straightness, and polish of the plates, by a process both more agree-
able to the workman and more speedy in its action than the old process of
hammering. After having been sufficiently pressed, the plate or plates are
taken out of the frame and finally polished by hand or by mechanical polishers,
arranged like small ivory saws, worked by a crank and connecting rod, which
will impart a rapid rotatory motion thereto. Any other convenient arrange-
ment, however, may be adopted in conjunction with the polishing tables, shewn
at Figures 1 and 2. The work is now tested, by taking a daguerreotype proof
to see if any imperfections occur in the plate.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe, in conclusion, that I do not confine or restrict myself
to the precise details or arrangements which I have had occasion to describe
or refer to, as many variations may be made therefrom without deviating from
the principles or main features of the said Invention; but what I consider to
be novel and original, and therefore claim as the Invention secured to me by
the herein-before in part recited Letters Patent is,―
First, the system or mode of flattening metal plates by the substitution of
pressure for the hammering process hitherto adopted.
Second, the construction and arrangement of polishing table, as herein-
before described.
Third, the application and use of the hinged metal frame in conjunction with
the-pressing blocks, as herein-before described.
Fourth, the application and use of rollers for straightening metal plates, as
herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, the Twenty-seventh day of October, One thousand
eight hundred and fifty-four.
T TENDV
JOHNSON
J. HENRY JOHNSON (10)