AN IMPROVED MODE OF TREATING THE MOULDS OR PACKETS EMPLOYED IN THE MANUFACTURE OF GOLD LEAF AND OTHER METAL FOILS
Year: 1864

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of "AN
IMPROVED MODE OF TREATING THE MOULDS OR PACKETS EMPLOYED IN THE
MANUFACTURE OF GOLD LEAF AND OTHER METAL FOILS."-A communica-
tion from abroad by Eugène François Paul Bazin, Auguste Michel
Daude, and Eugène François Daude, all of Paris, in the Empire- of
France.
Sealed the 12th May 1865, and dated the 17th November 1864.
PROVISIONAL SPECIFICATION left by the said John Henry' Johnson
at the Office of the Commissioners of Patents, with his Petition, on the
17th November 1864.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention for
"AN IMPROVED MODE OF TREATING THE MOULDS OR PACKETS EMPLOYED IN THE
MANUFACTURE OF GOLD LEAF AND OTHER METAL FOILS," a communication to
me from abroad by Eugène François Paul Bazin, Auguste Michel Daude,
and Eugène François Daude, all of Paris, in the Empire of France.
This Invention relates to an improved mode of drying the moulds or
packets of vellum leaves employed by gold-beaters and other metal foil manu-
facturers, whereby considerable economy of time and labor is obtained, whilst
the work is performed in a more efficient manner than heretofore.

page_text: The essential feature of this Invention consists in submitting the moulds or
packets occasionally to the action of a vacuum or partial vacuum obtained
either by the aid of the well-known air pump or in any other suitable or well-
known manner. The moulds or packets are first warmed in a hot press, and
then placed under the receiver of an air pump, or otherwise submitted to the
action of a vacuum or partial vacuum, which has the effect of expelling all
moisture therefrom. In some cases the moulds may be taken direct from the
hammer and placed in a vacuum for a short time.
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
17th May 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of November, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-eighth 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 Inven-
tion for "AN IMPROVED MODE OF TREATING THE MOULDS OR PACKETS EMPLOYED
IN THE MANUFACTURE OF GOLD LEAF AND OTHER METAL FOILS," a communica-
tion to me from abroad by Eugène François Paul Bazin, Auguste Michel
Daude, and Eugène François Daude, all of Paris, in the Empire of France,
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.

page_text: NOW KNOW YE, that I, the said John Henry Johnson, 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, that is to say :-
The said Invention relates to an improved mode of drying the moulds or
packets of vellum leaves employed by gold-beaters and other metal foil manu-
facturers, whereby considerable economy of time and labour is obtained, whilst
the work is performed in a more efficient manner than heretofore.
The essential feature of this Invention consists in submitting the moulds or
packets occasionally to the action of a vacuum or partial vacuum, obtained
either by the aid of the well-known air pump, or in any other suitable or
well-known manner. The moulds or packets are first warmed in a hot press
heated by gas, steam, or otherwise, and then placed whilst at a temperature
of from 100° to 160° Fahrenheit under the receiver of an air pump, or other-
wise submitted to the action of a vacuum or partial vacuum (according to the
state of humidity of the atmosphere or of the degree of moisture of the
packet) which has the effect of expelling all moisture therefrom. In some
cases the moulds may be taken direct from under the hammer of the beater
and placed in a vacuum or partial vacuum for a short time. The moist
vapour deposits in the form of drops upon the inner sides of the receiver, and
a very few minutes are requisite to complete the operation, after which the
packet is removed from the receiver and cooled by fanning, when it is again
ready for use. Whilst in the receiver the packet should be placed between
boards, but should not be compressed, so that the vacuum may operate freely
upon all the leaves. The advantages derivable from the use of this Invention
are economy in time, labour, and fuel, greater certainty in the work and
efficiency in the moulds; saving in plant, as the same work may be produced
with a less number of moulds than heretofore; reduction in the wear and
tear of the moulds, since they are not subjected to such frequent alternations
of heat and cold, as the moulds under the improved system of drying do not
require to be warmed oftener than from 1 to 3 times a day, and are then
heated only to a low temperature; possibility of preparing the moulds one or
even two days in advance, their bygrometric condition not sensibly changing
under forty or fifty hours, a result which is not obtainable under the existing
methods.
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 what I consider to be novel
and original, and therefore claim as the Invention secured to me by the herein-

page_text: before in part recited Letters Patent is, the drying of the moulds or packets
employed in the manufacture of gold leaf or other metal foils by submitting
them to the action of a vacuum or partial vacuum as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, the Seventeenth day of May, One thousand eight
hundred and sixty-five.
J. HENRY JOHNSON. (L.B.)