IMPROVEMENTS IN PREPARING CERTAIN UNBLEACHED LINEN FABRICS
Year: 1855

page_text: LETTERS PATENT to Arthur Dobson, of Belfast, in the County of Antrim,
in Ireland, Bleacher, for the Invention of "IMPROVEMENTS IN PREPARING
CERTAIN UNBLEACHED LINEN FABRICS."
Sealed the 22nd April 1856, and dated the 5th November 1855:
PROVISIONAL SPECIFICATION left by the said Arthur Dobson at the
Office of the Commissioners of. Patents, with his Petition, on the 5th
November 1855.
I, ARTHUR DOBSON, of Belfast, in the County of Antrim, in Ireland, Bleacher,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
PREPARING CERTAIN UNBLEACHED LINEN FABRICS " to be as follows:-
The object of my Invention is to impart to fabrics in the brown state, made
of Irish or other inferior, flax, (intended for coatings, blouses, waistcoatings,
and other purposes,) the appearance of fabrics made of Courtrai or other flax
of superior quality. This effect is produced, first, by steeping the linen fabrics
in the ordinary manner, and then. submitting them to the action of
infusion of straw, hay, the roots or plant of hemlock, or the plant or seeds
of flax or hemp. The fabrics may be prepared by the action of acids or
salts, if requisite.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Arthur Dobson in the Great Seal Patent Office on the
5th May 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
DOBSON, of Belfast, in the County of Antrim, in Ireland, Bleacher, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of November, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Arthur Dobson, Her special license, that I, the said Arthur
Dobson, my executors, administrators, and assigns, or such others as I,
the said Arthur Dobson, 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 "IM-
PROVEMENTS IN PREPARING CERTAIN UNBLEACHED LINEN FABRICS," upon the con-
dition (amongst others) that I, the said Arthur Dobson, 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 Arthur. Dobson, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
Specification thereof (that is to say):-
The nature of my said Invention of improvements in preparing certain
unbleached linen fabrics consists in imparting to fabrics in the brown or
unbleached state, made of Irish or other inferior flax, the appearance of fabrics
made of Courtrai or other flax of superior quality. This effect is produced by
steeping the fabrics to be operated upon in the ordinary. manner, and then
submitting them to the action of an infusion of straw, hay, the roots or plant of
hemlock, or the plant or seeds of flax or hemp.
And in order that my Invention may be fully understood, and readily carried
into effect, I will proceed to describe the means pursued by me.

page_text: I steep the fabrics to be operated upon in lukewarm water, or in used soda
ash, ley, or other suitable medium, so as to remove as much as possible of the
dressing, loose grease, or other foreign matters; then I thoroughly wash. the
fabric, preferring to do so through a washing mangle, as it is thus kept at its
full width and free, from creases. Afterwards, where great, nicety or depth.
of shade is required, I dry the fabric, making use, whenever practicable, of
Bridson's improved patent stenter frame; I next run the fabric, through,
one of the following infusions, made up in a dye box. I sometimes simply
immerse the fabric in the infusion, and sometimes I boil the fabric with the
components of the infusion, but I generally place the infusion in a dye box
and run the fabric through it, keeping the liquid at a boiling heat. For a
dark rich flax shade, for fifty pieces of fabric of fifty-four yards each, about
fourteen pounds of meadow or grass seed hay to seventy gallons of water
boiled six or seven hours. When flax plant or hemp plant is used, about
twelve pounds of the plant to seventy gallons of water, boiled from four to six
hours; or flax seed or hemp seed, about five pounds to seventy gallons of
water (containing sometimes about two pounds of soda ash in solution) boiled
five or six hours. For a rich lighter shade, about fourteen pounds straw of
oats or wheat to seventy gallons water boiled six or seven hours. For a rich
medium shade of depth, about ten pounds of the withered stems and leaves
of hemlock to eighty gallons of water boiled from five to seven hours; of the
roots of hemlock, about three to five pounds to seventy gallons water boiled
from six to eight hours. I use all the above-named vegetable productions both
whole.and. bruised. Having run the fabric through or otherwise sufficiently
treated with the infusion, I allow it to remain in "bunches" or lots of four or
five pieces lying one upon another for about an hour, and then carefully wash
it at width in a water mangle; after this the fabric is sometimes again dried.
The fabric is then ready for the starcher, from whose hands it is sent to be
finished in the usual manner.
I wish to observe that before submitting the cloth to the infusion, I sometimes
treat it with more or less dilute solution of alum or acids for the purpose of
giving an under shade of red; of soda ash, for giving a greater depth of dark
shade; of bleaching powder, for rendering the ground more even. The use of
these preparations depends entirely on the nature of the yarn in the fabric; I
find them more useful to the very finest and very coarsest descriptions of fabric;
the solutions are used cold or of various temperatures. Fabrics made of Irish
or other inferior flax when thus operated upon are made to assume the
appearance of fabrics made of Courtrai or other superior flax.
Having thus particularly described the nature of my Invention, and the

page_text: manner of performing the same, I wish it to be understood that I do not
limit myself to the proportions given, nor to the length of time required. for
the processes, as much depends upon the strength of the ingredients, the quality
of the fabrics to be prepared, and the shade or color to be produced; but I
claim the application and use of infusions of straw, hay, the roots or plant
of hemlock, and the plant or seeds of flax or hemp, for preparing unbleached'
linen fabrics, in the manner and for the purpose described.
In witness whereof, I, the said Arthur Dobson, have hereunto set my'
hand and seal, this First- day of May, in the year of our Lord One
thousand eight hundred and fifty-six.
ARTHUR DOBSON. (L.S.)