AN IMPROVED PROCESS FOR THE BOILING OFF OF TUSSAH SILKS OR WILD SILKS
Year: 1858

page_text: LETTERS PATENT to Jean Ulrich Faessler Petzi, of Lyous, in the Empire
of France, Merchant, for the Invention of "AN IMPROVED PROCESS FOR
THE BOILING OFF OF TUSSAH SILKS OR WILD SILKS,"
Sealed the 18th February 1859, and dated the 8th September 1858.
PROVISIONAL SPECIFICATION left by the said Jean Ulrich Faessler
Petzi at the Office of the Commissioners of Patents, with his Petition,
on the 8th September 1858.
1, JEAN ULRICH FAESSLER PETZ1, of Lyons, in the Empire of France,
Merchant, do hereby declare the nature of the said Invention for "AN
IMPROVED PROCESS FOR THE BOILING OFF OF TUSSAH SILKS OR WILD SILKS," to be
as follows:-
Firstly, in submitting the said silks to three baths (of from one to six hours)
of soda, potash, or even caustic potash.
Secondly, a fourth bath (of about three-quarters of a hour) of potash and
chloride of lime. After these operations, the silks must be well washed in
cold water, and then passed through a fifth bath very strong (of about ten
minutes to a quarter of an hour) either of hydrocloric or muriatic acid, or of
sulphuric acid. If it is desired, to render these silks more brilliant, they must
be submitted for about ten minutes to aquafortis or nitric acid diluted with
water.
After these operations the silks must be again well washed in cold water,
and finally cylindered.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jean Ulrich Faessler Petzi in the Great Seal Patent Office
on the Sth March 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN
ULRICH FAESSLER PETZI, of Lyons, in the Empire of France, Merchant, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent. bearing date the Eighth day of September, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Jean Ulrich Faessler Petzi, Her special licence that 1, the said
Jean Ulrich Faessler Petzi, iny executors, administrators, and assigns, or such
others as I, the said Jean Ulrich Faessler Petzi, 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 "AN IMPROVED PROCESS FOR THE BOILING OFF OF TUSSAH SILKS OR
WILD SILKS, upon the condition (amongst others) that I, the said Jean Ulrich
Faessler Petzi, 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 Jean Ulrich Faessler Petzi, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:
My improved process for the boiling off of tussal silks or wild silks consists,
firstly, in submitting the said silks to three baths (each of from one to six
hours duration) composed of soda, or potash, or caustic potash, or of a mixture
of the three dissolved in water, in the proportion of about eleven pounds of
soda, eleven pounds of potash, and 8 ounces of caustic potash, to 325 pounds
of water
Secondly, in submitting the said silks subsequently for about three-quarters
of an hour to a fourth bath composed of a solution of potash and chloride of

page_text: jime, in the proportion of abou: eleven pounds of potash and two pounds 6
ounces of chloride of lime to 325 pounds of water.
After these operations, the silks must be well washed in cold water, and then
submitted (for about ten minutes to a quarter of an hour) to a fifth bath com-
posed of hydrochloric or muriatic acid diluted with water, say, in the proportion
of twenty-two pounds of the muriatic or hydrochloric acid to 325 pounds of
water.
If it is desired further to increase the brilliancy of the silks thus treated,
they may submitted for about ten minutes to aquafortis or nitric acid very
much diluted with water.
After these operations, the silks must be well washed in cold water, and
then passed between drawing rollers, whereby the silk is elongated, and at the
same time rendered more brilliant.
Having thus described the nature of my 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 proportions herein before given, as the same may be varied
without departing from the nature of my Invention; but I claim in respect
thereof, the submitting Tussah silks or wild silks to baths composed of the
materials herein-before described.
In witness whereof, I, the said Jean Ulrich Faessler Petzi, have hereunto
set my hand and seal, this Twenty-eighth day of February, in the year
of our Lord One thousand eight hundred and fifty-nine.
5
רי
Witness,
E. MILSONE,
Silk Merchant,
Lyons.
JEAN ULRICH FAESSLER PETZL. (L.s.)