CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF CANVAS OR STRONG CLOTHS OF VEGETABLE MATERIALS, FOR SAILS, TENTS, PACKAGES, AND OTHER USEFUL PURPOSES
Year: 1803

page_text: DEMPSTER'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CATHICART
DEMPSTER, of Saint Andrews, North Britain, Gentleman, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Thirtieth day of August,
in the forty-third year of His reign, give and grant unto me, the said Cathcart
Dempster, His especial licence, that I, the said Cathcart Dempster, during the
term of years therein mentioned, should and lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed,
my Invention of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF CANVAS OR
STRONG CLOTHS OF VEGETABLE MATERIALS, FOR SAILS, TENTS, PACKAGES, AND OTHER
USEFUL PURPOSES;" in which said Letters Patent there is contained a proviso
obliging me, the said Cathcart Dempster, by an instrument in writing under
my hand and seal, to cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, to be inrolled in
His Majesty's High Court of Chancery within four calendar months after the
date of the said recited Letters Patent, as in and by the same (relation being
thereunto had) may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Cathcart Dempster, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, are described as
followeth, that is to say:-
Instead of using single yarns not twisted but glued together with starch or
other mucilage, in order to form the warp of the canvas, as is now commonly

page_text: done to the great injury of the article, by rendering it liable to spontaneous
destruction by mildew, I use twine composed of two or more yarns of prime
material of equal size and strength, both for the warp and woof, and I am by that
means enabled to weave, and I do weave, my canvas without starch or any
other mucilage whatever, and do thereby produce an article nearly twice as
strong as common canvas of the same weight and fineness, and with the
advantage that its threads have an equal bearing on one another in all direc-
tions, not liable like the common canvas to split longitudinally, being much
stronger in the cross direction, not capable of rot or mildew from the presence
of mucilage, and extremely durable, because it is subject to no irregular action
of sharp cutting threads on its woof, but is only exposed to the fair, slow, and
gradual wear of its well combined and duly proportioned component parts,
which maintain their relative strength to the last.
In witness whereof, I, the said Cathcart Dempster, have hereunto set
my hand and seal, this Seventh day of September, in the
F. P. STRATFORD.
CATHCART DEMPSTER. (L.S.)
AND BE IT REMEMBERED, that on the same Seventh day of September,
in the year above mentioned, the aforesaid Cathcart Dempster came before
our Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained, in forin above written.
And also the Specification aforesaid was stamped according to the tenor of the
Statute in that case made and provided.
Inrolled the Eighth day of September, in the year above written.