THE EXTRACTION, PREPARATION, AND SPINNING OF THE SILKY FIBRE CONTAINED IN THE BARK OF MULBERRY TREES, AND THE MANUFACTURE OF THE SAME INTO TEXTILE FABRICS
Year: 1862

page_text: LETTERS PATENT to Pasquale Potenza, of Naples, in the Kingdom of
Italy, Commander, for the Invention of "THE EXTRACTION, PREPARATION,
AND SPINNING OF THE SILKY FIBRE CONTAINED IN THE BARK OF MULBERRY
TREES, AND THE MANUFACTURE OF THE SAME INTO TEXTILE FABRICS."
Sealed the 27th March 1863, and dated the 15th October 1862.
PROVISIONAL SPECIFICATION left by the said Pasquale Potenza at
the Office of the Commissioners of Patents, with his Petition, on the
15th October 1862. .
I, PASQUALE POTENZA, of Naples, in the Kingdom of Italy, Commander, do
hereby declare the nature of the said Invention for "THE EXTRACTION, PRE-
PARATION, AND SPINNING OF THE SILKY FIBRE CONTAINED IN THE BARK OF MULBERRY
TREES, AND THE MANUFACTURE OF THE SAME INTO TEXTILE FABRICS," to be as
follows:-.
My Invention consists in extracting and preparing a certain fibrous sub-
stance contained in the bark of mulberry trees, in order to produce therefrom
fine, soft, but yet strong filaments, partaking in a high degree of the lustrous
appearance, elasticity, and other essential qualities of silk, which filaments I
then spin into a silky thread, and manufacture the same into textile fabrics.

page_text: The bark requisite for this purpose may be obtained without detriment to
the mulberry trees, as that which is on the small branches obtained by lopping
the trees is particularly applicable for the purpose. The bark after careful
separation from the wood is subjected to a process of thorough dessication,
which process should take place very gradually, by preference in the open air,
and under a moderate action of the sun, as otherwise the bark would rot,
forming the so called "maca," and the fibrous substance which it is desired to
extract would be totally destroyed. When the bark is thoroughly dried, the
fibrous substance, which will then be found contained in the same in the form
of agglomerated filaments of an exceedingly fine texture, is carefully extracted
by hand, and separated from all extraneous matter with which it is combined,
such as the epidermis, and the various layers of bark. These masses of
filaments after being extracted from the bark are then prepared for use, firstly,
by carefully separating the filaments in a lateral direction, (and not in a
longitudinal direction, which would destroy the filaments), which separation I
effect by hand; and, secondly, by carding the same by means of the ordinary
carding machine employed for carding cotton, the length of the filaments or
fibres of this "vegetable silk," as it may be termed, being as near as possible
the same as that of the cotton fibre. I then proceed to spin the fibre after
such preparation into thread, for which purpose I employ any of the known
processes and machinery employed for spinning cotton; and such thread I
then employ for weaving into fabrics, either by itself or in combination with
silk or wool, or other known fibrous material, its glossy and elastic nature, as
also its great strength, rendering the fabrics made from the same almost equal
to the finest silk fabrics.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Pasquale Potenza in the Great Seal Patent Office on the
14th April 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PASQUALE
POTENZA, of Naples, in the Kingdom of Italy, Commander, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date: the Fifteenth day of October, in the year of our
Lord One thousand eight hundred and sixty-two, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Pasquale Potenza, Her special licence that I, the said Pasquale

page_text: Potenza, my executors, administrators, and assigns, or such others as I,
the said Pasquale Potenza, 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 "THE
EXTRACTION, PREPARATION, AND SPINNING OF THE SILKY FIBRE CONTAINED IN
THE BARK OF MULBERRY TREES, AND THE MANUFACTURE OF THE SAME INTO
TEXTILE FABRICS," upon the condition (amongst others) that I, the said
Pasquale Potenza, 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 Pasquale Potenza, 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 Invention consists in extracting and preparing a certain fibrous sub-
stance contained in the bark of mulberry. trees, in order to produce therefrom
fine, soft, but strong filaments, which I term " vegetable silk," partaking in a
high degree of the lustrous appearance, elasticity, and other essential qualities
of silk, which filaments I then spin into a silky thread, and manufacture the
same into textile fabrics.
The bark requisite for this purpose may be obtained in very large quantities
without detriment to the mulberry trees, inasmuch as that which is upon the
small branches or twigs of the trees, and which is annually or biennially cast
off to the extent of about 20 lbs. from every tree of average growth, is
particularly applicable for the purpose, 100 lbs. weight of such bark. yielding
nearly. 15 lbs. of the silky fibre or "vegetable silk." The bark after careful
separation from the wood is subjected to a process of thorough dessication,
which process should take place very gradually; by preference in the open air,
and under very moderate action of the sun, as otherwise the bark would rot,
forming the so-called "maca," and the fibrous substance which it is desired to
extract would be totally destroyed. When the bark has been thoroughly dried,
the fibrous substance, which will then be found in the same in the form of
agglomerated filaments-of-an-exceedingly fine texture, is carefully extracted by

page_text: separating from it all extraneous matter that will be found adhering to it,
such as the epidermis, the green bark or rind resembling a skin, and the liber,
whenever this is found next the sap (as it is not always there). This
separation of the silky fibre from the various layers of bark, and from all
other substances by which they are held cemented together to a certain extent,
is effected most readily by boiling the bark, either in water alone, or with the
admixture, by preference of a mineral acid, or of a vegetable alkali combined
with the base of an oil or fat; or I sometimes employ a mineral alkali, or
even vegetable acid for this purpose. By this means the masses of fibres or
filaments are not only freed from all extraneous matters and impurities, but
are rendered exceedingly soft, and capable of being separated from each other
in the most perfect manner. The duration of the process of purifying the
masses of fibre, and the separation therefrom of all foreign substances, will
have to depend entirely upon the judgment of the operator, who, when he
finds the fibre brought to the requisite state of purity, must terminate the
operation. The masses of fibre are then opened out, either by the hand, or
by any machinery or apparatus suitable for the purpose, the separation being
effected by preference in a lateral direction, or across the fibres, which have
already to a certain extent a parallel position to each other, and which would
not be so effectually separated if operated upon in the direction of their length.
After being thus opened out the fibres may then be still further separated, and
placed parallel to each other by being subjected to the operation of a carding
engine of similar arrangement to those employed for carding the cotton fibre,
the length of staple of this "vegetable silk" corresponding as nearly as possible
with that of the cotton fibre. Or any other suitable known machinery or
apparatus may be employed to effect the above-named operation. The
vegetable silk is then formed into "slivers" by the known processes of
"doubling" and "stretching," so as to effect the more or less perfect
parallelism of the fibres, and is spun into thread of any degree of fineness by
means of any of the known processes and apparatus employed for spinning
the cotton fibre. The silky thread thus obtained is of an exceedingly strong,
elastic, and glossy nature, partaking in a high degree of the qualities of the
best silk, and it may therefore be employed with great advantage, particularly
for forming the woof in silken fabrics, as also for being manufactured into
textile fabrics, either by itself or in combination with wool, cotton, or any
other fibrous material.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that what I
claim under the herein-before in part recited Letters Patent, is,―

page_text: Firstly, the extraction, preparation, and spinning of the silky fibre con-
tained in the bark of mulberry trees, for the purpose of rendering it applicable
to various branches of arts and manufactures.
Secondly, the application of such silky fibre, either alone or in combination
with other materials, to the manufacture of textile fabrics.
In witness whereof, I, the said Pasquale Potenza, have hereunto set my
hand and seal, this Twenty-third day of March, in the year of our Lord
One thousand eight hundred and sixty-three.
PASQUALE POTENZA. (L.S.)