A NEW ESCAPEMENT, AND ALSO A BALANCE TO COMPENSATE THE EFFECTS ARISING FROM HEAT AND COLD IN POCKET CHRONO- METERS OR WATCHES, AND FOR INCURVATING THE TWO ENDS OF THE HELICAL SPRING, TO RENDER THE EXPANSION AND CONTRACTION OF THE SPRING PERFECTLY CONCENTRIC WITH THE CENTER OF THE BALANCE OR VERGE,
Year: 1782

page_text: TO ALL. TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ARNOLD, of the Adelphi, in the County of Middlesex, Watchmaker, send
greeting.
WHEREAS I, the said John Arnold, did, by my petition, humbly represent
to His present most Excellent Majesty King George the Third, that after some
labour and expence I had invented "A NEW ESCAPEMENT, AND ALSO A BALANCE
TO COMPENSATE THE EFFECTS ARISING FROM HEAT AND COLD IN POCKET CHRONO-
METERS OR WATCHES, AND FOR INCURVATING THE TWO ENDS OF THE HELICAL SPRING,
TO RENDER THE EXPANSION AND CONTRACTION OF THE SPRING PERFECTLY CONCENTRIC
WITH THE CENTER OF THE BALANCE OR VERGE," which would be of great publick
utility; wherefore, in regard I was the first and true Inventor thereof, and
that the same had not been made use of by any other person or persons to my
knowledge or belief, I, therefore most humbly prayed His said Majesty that
He would be graciously pleased to grant unto me, the said John Arnold, my
executors, administrators, and assigns, His Royal Letters Patent, for the sole
use and benefit of my said Invention, within that part of His said Majesty's
Kingdom of Great Britain called England, His Dominion of Wales, and Town
of Berwick-upon-Tweed, for the term of fourteen years, according to the Statute
in that case made and provided; His said Majesty being willing to give
encouragement to all arts and inventions which might be for the publick good,
was graciously pleased to condescend to my request; and, therefore, by His
Royal Letters Patent under His Great Seal of Great Britain, bearing date at
Westminster, the Second day of May, in the twenty-second year of His reign.

page_text: of His especial grace, certain knowledge, and mere motion, for Himself, His
heirs and successors, did give and grant unto me, the said John Arnold, my
executors, administrators, and assigns, His especial licence, full power, sole
privilege and authority, that I, the said John Arnold, my executors, adminis-
trators, and assigns, and every of them, by myself and themselves, or by mine
or their deputy or deputies, servants or agents, or such others as I, the said
John Arnold, my executors, administrators, or assigns, should agree with, and
no others, from time to time and at all times thereafter during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend my said Invention within that part of His said Majesty's Kingdom of
Great Britain called England, His Dominion of Wales, and Town of Berwick-
upon-Tweed, in such manner as to me, the said John Arnold, my executors,
administrators, and assigns, or any of us, should, in our discretions seem meet;
and that I, the said John Arnold, my executors, administrators, and assigns,
should and lawfully might have and enjoy the whole profit, benefit, comodity,
and advantage from time to time coming, growing, accrueing, or arising by
reason of the said Invention, for and during the term of years therein men-
tioned; to have, hold, exercise, and enjoy the said licence, powers, privileges,
and advantages therein-before granted or mentioned to be granted unto me,
the said John Arnold, my executors, administrators, and assigns, for and
during and unto the full end and term of fourteen years from the date of the
said Letters Patent, next and immediately ensuing, and fully to be complete
and ended, according to the Statute in that case made and provided; in which
said Letters Patent is contained a proviso that if I, the said John Arnold,
should not particularly describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, by an instrument in writing
under my hand and seal, and cause the same to be inrolled in His said
Majesty's High Court of Chancery within four calendar months next and
immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
should utterly cease, determine, and become void, anything therein-before
contained to the contrary thereof in anywise nothwithstanding, as in and by
the said in part recited Letters Patent (relation being thereunto had) will more
fully and at large appear.
NOW KNOW YE, that I, the said John Arnold, in compliance with the
said proviso, do hereby describe and ascertain the nature of my said Invention,
and declare that the plan thereof drawn in the margin of these Presents is
composed of the several particulars, and to be performed in manner following
(that is to sav):-

page_text: The tooth of the balance wheel A is an epicycloid, that acts upon the pallet B,
which in the part of action is a strait line from the outer edge of the pallet to
the center of the verge. The scape wheel rests on a single spring, whilst the
balance is vibrating, until it is unlocked to add new impulse to the balance.
The incurvating the ends of the helical spring C is attended with the property
of rendering all the vibrations of equal duration, because the figure is always
similar to itself. The balance is adjusted by two pieces of compound metal,
which are placed, as in the margin, by three or more different ways, as the
curv'd S, the strait piece T, and two circular pieces U, for compensating the
effects of heat and cold.
In witness whereof, I, the said John Arnold, have hereunto set my hand
and seal, the Thirty-first day of August, in the twenty-second year of
the reign of our said Sovereign Lord George the Third, by the grace
of God, of Great Britain, France, and Ireland King, Defender of the
Faith, and so forth, and in the year of our Lord One thousand seven
hundred and eighty-two.
Sealed and delivered (being first duly
stampt) in the presence of
BIGOE HENZELL.
ROBERT LEMON.
JOHN ARNOLD. (L.S.)
AND BE IT REMEMBERED, that on the Thirty-first day of August, in
the twenty-second year of the reign of His Majesty King George the Third,
the said John Arnold came before the said Lord the King, in His Chancery,
and acknowledged the instrument aforesaid, and all and every thing therein
contained and specified, in form above written. And also the said instrument
was stampt according to the tenor of the Statutes made in the sixth year
of the reign of the late King and Queen William and Mary, of England, and
in the seventeenth year of the reign of His said Majesty King George the
Third.
Inrolled the said Thirty-first day of August, in the year above written.