CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF CHRONOMETERS
Year: 1812

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
.MASSEY, of Crossheath, near Newcastle-under-Lime, in the county of Stafford,
Nautical Instrument Maker, send greeting.
WHEREAS IIis 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 April, in the fifty-second year of His reign, give and grant unto me, the
said Edward Massey, my exors, adiiors, and assigns, His especial licence, full
power, sole privilege and authority, that I, the said Edward Massey, my
exors, admors, and assigns, should and lawfully might, during the term of
years therein mentioned, make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "CERTAIN
IMPROVEMENTS IN THE CONSTRUCTION OF CHRONOMETERS;" in which said Letters
Patent there is contained a proviso, that if I, the said Edward Massey,
shall 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 Majesty's
High Court of Chancery within six 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, shall utterly
cease, determine, and become void, as in and by the same (relation being
thereunto had) may more fully and at large appear:

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Edward Massey, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say) :-
Plate 1, Fig. 1, is a back view of an 8 days' marine time keeper, making two
vibrations in one second, and carries a balance a, weighing about two ounces,
and being about two inches in diameter, having the greater part of its weight
in the extream; but the number of vibrations, weight, and make of balance
may be varied as may be found most advantageous. This balance has about
7/8 of its weight suspended by a thread b, attached to a box c, containing a
spring which is wound up till its tension is within about 1/8 of raising the
balance, but may be varied to any other proportional part that may be found
most convenient. A weight may answer over the pulley instead of the spring
in box c. The verge, as represented in the Drawing, having but one pivot,
may be about ten or twelve inches long, so as to prevent it as much as possible
from being agitated by jolts, &c. At e is a stud to which the pendulum spring
is attached. The pivot is made, as represented by Fig. 2, with an opening in
the side for the axis of the verge, which passes in a groove over the shoulder f
to prevent the pivot from being flung out of the hole by a jolt. Fig. 3 is a
flat view of the side shewn in Fig. 2. Fig. 4 shows the counter wheel, pallet
wheel, and pallets. At a is a fork which when placed in action receives tlie
pallet of verge d, Fig. 1, and communicates its impulse. This escapement, as
it is particularly calculated for pocket watches, will be described more particu-
larly hereafter. One advantage of marine time keepers made as Fig. 1 is, that
they shew the time of the day vertically, the pallet wheel, pallets, and balance
at the same time moving horizontally; and the best method possible should be
adapted when at sea to keep the machine upright, so that the balance may
move as near as possible in an horizontal direction. My motive for suspend-
ing the greater part of the weight of the balance on a thread is to avoid or
reduce the friction which takes place on the verge pivots; but it may be made
without the thread, with the usual length of verge, on two pivots, as it will
take some time to determine whether a thread under all circumstances at sea
may be better than pivots.
Description of the escapement in its distinct parts.-Fig. 5 is the pallet
wheel which gives the impulse to the cylindrical pallet Fig. 6, which are
secured on their axis Fig. 7 by pins, as shown by dots on the surface. The
lever Fig. 8 is likewise secured on the axis Fig. 7 at a, and its fork point
communicates impulse to the pallet of verge Fig. 9, the cylindrical part of

page_text: which answers to keep the lever in a proper situation to receive the pallet into
it on the return of each vibration, when it unlocks the pallets in the wheel,
and receives the impulse alternately. The cylindrical part will answer in two
ways. 1st, when the impulse is given to the pallet, the cylinder may carry
the fork or lever a little farther, which will cause the pallets to lock deeper in
the wheel, and altho' the fork point will have little or no pressure against the
cylinder, it can hardly be said in this case to be detached by making the lever
longer, so that while the wheel is communicating the impulse the fork point of
the lever moves thro' more space, and clears the cylinder; but the locking of
these kind of palletts being so very light that the lever when it has given the
impulse recoils from the banking pins a, a, Fig. 8, and touches the cylinder,
I have not found any inconvenience on this account in the going of a watch
made on this principle; but to do away this objection a fly may be applied,
made as Figs. 10 and 10, and fixed on the axis of the lever, and their points
pressed gently against each other by a collet, so that when the lever is alter-
nately flung against the banking pins the fly sliding a little on the axis
prevents it from recoiling. The verge, which is the most principal part of the
improvement in this escapement, may be applied with pallets over three teeth,
but the nick in the lever in either case should be as small as possible, so that
when it begins to give the impulse to the verge the pallet may nearly be in a
straight line with the axis of the verge and pallets. The shape of the lever
may be altered for the conveniency of poising in pocket watches, as well as the
length and also size of the pallet. Fig. 11 is a front view of a cross dead beat
counter wheel escapement. a is the pallet wheel; b, b, the cross pallet to
which the wheel gives the impulse; c is the staff on which the pallets are
screwed. Fig. 12 is a side view of the last Fig., and shews the action of the
wheel on the pallets. Fig. 13 is a front view of a counter wheel dead beat
escapement, which locks on the inner part of both pallets. a is the wheel;
b, b, the pallets; c, the axis on which the pallets are fixed. Fig. 14 is an end
view of Fig. 13, and shews the action of the wheel on the pallets. The two.
last escapements communicate their impulse by means of a lever to the verge
pallet in the same way as described above.
+
The recoiling cylinder escapement.-Fig. 15 represents a cylinder or pallet
wheel, with inclined planes on its teeth. At each vibration an impulse is
communicated to the cylinder a by the teeth. Fig. 16 is the axis of the
cylinder, with a notch cut in it to allow the pallet wheel to pass through the
center of the cylinder. This escapement recoils in the inner pallet, but does
not recoil on the outer one, and will be of much easier construction than the
common cylinder escapement. Fig. 17 shews the method of applying the last-
described escapement to a vertical watch.
a is a pottence.

page_text: Description of a method of reducing the friction in the verge of pendulum
chronometers. The verge a, pallets a, a, and crutch or connecting point y,
are similar to those used in common regulators, with the difference only of the
crank b. In the center of the crank is a small hole c, which should always be
the equilibriam point of the verge when the pallets and crutch are on, or an
adjusting ball may be fitted on the axis for the purpose of poising the verge.
d is a thread, one end of which passes through the small hole c. e is a cock
to which is affixed a small pully f, over which the thread & passes to another
pully g, which is also affixed to cock h. At the end of the thread is sus-
pended a weight i, in order to poise or balance the verge in whole or in
part, and thus diminish the friction on the pivots by reducing the pressure
on them.
Description of an improvement in stop watches by which the seconds may
be stopped though the watch continues going.-Fig. 19 represents 4th wheel
and pinion of a lever watch. The pinion is perforated through its center to
receive the axes. Fig. 20 is an axis. Fig. 21 is a spring placed on the axis
against the shoulder at a, then the wheel and pinions put on, and a collet is
made to bind axis so as to press the wheel against the spring till its tension is
sufficient to carry round the plain wheel and seconds hand. The stop work
may be made in the common way, excepting that it should come in contact
with the plain wheel on the axis at b, by which means the axis and seconds
hand become stopped, and the wheel and pinion continue going. This
improvement may be applied to watches of various constructions.
In witness whereof, I, the said Edward Massey, have hereunto set my.
hand and seal, this Twenty-seventh day of October, in the year of our
Lord One thousand eight hundred and twelve.