A Perpetual Calendar and Watch Trinket or Charm.
Year: 1891

page_text: Date of Application, 13th Feb., 1891
Complete Specification Left, 5th Nov., 1891-Accepted, 5th Dec., 1891
PROVISIONAL SPECIFICATION.
A Perpetual Calendar and Watch Trinket or Charm.
I, EUSTACHE AUGUSTE CRESSON of 18 Rue Jean Jacques Rousseau, Paris,
France; Gentleman do hereby declare the nature of this invention to be as
follows:-
My invention relates to a perpetual calendar especially suitable for attachment
to a watch-chain in the manner of a coin, medal, or charm. The calendar consists
essentially of a ring within which a disc is fitted to revolve, the ring and disc being
divided into segments inscribed for reference the one to the other, in the manner
Hereinafter described, for the purposes for which such a calendar is required.
In the accompanying drawings, forming part of this Specification,
Figure 1 represents the side of the calendar, bearing upon the rotating disc the
names of the months, and
Figure 2 the opposite face bearing the days of the month, the inscriptions on both
faces being contained in seven sector-shaped divisions-arranged in. a certain order.
The outer ring bears upon both faces the days of the week inscribed in segments
corresponding in length and number to the divisions of the disc.
Figure 3 represents the peripheral rim of the outer ring, developed in. the, flat,
bearing, in seven segments or divisions corresponding to those of the faces,
numbers by which to find the key to the instrument, which. is the first day of the
year.
Figure 4 shews the calendar as a watch trinket.
The day of the week on which the first day of the year falls being known, in
order to find the day of the week corresponding to any given date of any month,
the name of the said month is placed opposite the day of the week on which the first
day of the year falls and then by referring to the opposite face of the disc,. the date
of the month will be found below the name of the day sought.for..
First Example. To find on which day of the week the 21st March. 1891 will fall.
The first day of the year 1891 being known to be Thursday, the month of March is
to be placed opposite to Thursday by rotating the disc when it will be found on
referring to the opposite face of the calendar that the number 21 is opposite to
Saturday, thus shewing that the 21st March. 1891 will be. Saturday..
Second Example. To find the date of the second Saturday in October 1891.
Place October opposite to Thursday, January 1st 1891 and then find on the opposite.
face of the calendar the second date beneath the Saturday which is 10 consequently
the second Saturday in October 1891 is on the 10th day of the month.
To find the day of the week on which the first day of any year falls, which, as
above mentioned, forms the key to the use of the instrument, the one of the three
numbers 20, 48, 76 (inscribed upon the mouth. disc) which most nearly corresponds
to the number of the year in the century,. is to be subtracted therefrom and by
referring to the number on the rim corresponding to. the remainder the first day
of the year will be found beneath it, which is the key sought for. Or the year may
be divided by the constant number 28 which gives the same result..
Example for 1891. 9176 = 15 which is found. on. the rim above Thursday on
the face, thus shewing that the first day of the year was a Thursday. The key may
thus be found for any year in a similar manner..
If, in:subtracting in the above manner, the remainder is repeated on the rim, this
will indicate Leap Year in which case the following method is adopted.. For the
months of January and February, the key will be the day found upon the rim
below the first number to the right; from the month of March it will be the day
found below the second figure to the left. For example, the year 1892 is found

page_text: to be Leap Year as by subtracting from 92 the number most nearly approaching it
which is 76 there remains 16 which is found repeated twice upon the rim.
Below
the 16 on the right is found Friday which serves as the key for the months of
January and February and below the 16 to the left is found Saturday which forms
the key from March to the end of the year.
pruary
E. A. CRESSON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents:
COMPLETE SPECIFICATION.
A Perpetual Calendar and Watch Trinket or Charm.
I, EUSTACHE AUGUSTE CRESSON, of 18, Rue Jean Jacques Rousseau, Paris,
France, Gentleman, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
My invention relates to a perpetual calendar especially suitable for attachment
to a watch-chain in the manner of a coin, medal, or charm.
The calendar consists essentially of a ring within which a disc is fitted to revolve,
the ring and disc being divided into segments inscribed for reference the one to the
other in the manner hereinafter described for the purposes for which such a calendar
is required.
Reference is to be had to the drawings left with my Provisional Specification,
Figure 1 of which represents the side of the calendar, bearing upon the rotating
disc the names of the months, and
Figure 2 the opposite face, bearing the days of the month, the inscriptions on
both faces being contained in seven sector-shaped divisions arranged in a certain
order. The outer ring bears upon both faces the days of the week inscribed in
segments corresponding in length and number to the divisions of the disc.
Figure 3 represents the peripheral rim of the outer ring, developed in the flat,
bearing, in seven segments or divisions corresponding to those of the faces, numbers
by which to find the key to the instrument, which is the first day of the year.
Figure 4 shews the calendar as a watch trinket.
The day of the week on which the first day of the year falls being known, in
order to find the day of the week corresponding to any given date of any month,
the name of the said month is placed opposite the day of the week on which the
first day of the year falls and then by referring to the opposite face of the disc, the
date of the month will be found below the name of the day sought for.
First Example. To find on which day of the week the 21st March 1891 will
fall. The first day of the year 1891 being known to be Thursday, the month of
March is to be placed opposite to Thursday by rotating the disc when it will be
found on referring to the opposite face of the calendar that the number 21 is
opposite to Saturday, thus shewing that the 21st March 1891 will be Saturday.
Second Example. To find the date of the second Saturday in October 1891.
Place October opposite to Thursday January 1st 1891 and then find on the opposite
face of the calendar the second date beneath the Saturday which is 10 consequently
the second Saturday in October 1891 is on the 10th day of the month.
To find the day of the week on which the first day of any year falls, which, as
above mentioned, forms the key to the use of the instrument, the one of the
three numbers 20, 48, 76 (inscribed upon the month disc) which most nearly
corresponds to the number of the year in the century, is to be subtracted there-
from and by referring to the number on the rim corresponding to the remainder
the first day of the year will be found beneath it, which is the key sought for.
Or the year may be divided by the constant number 28 which gives the same
result.

page_text: Example for 1891. 9176 = 15 which is found on the rim above Thursday on
the face, thus shewing that the first day of the year was a Thursday. The key may
thus be found for any year in a similar manner.
If, in subtracting in the above manner, the remainder is repeated on the rim, this
will indicate Leap Year in which case the following method is adopted. For the
months of January and February, the key will be the day found upon the rim below
the first number to the right; from the month of March it will be the day found
below the second figure to the left. For example, the year 1892 is found to be
Leap Year as by subtracting from 92 the number most nearly approaching it which
is 76 there remains 16 which is found repeated twice upon the rim. Below the 16
on the right is found Friday which serves as the key for the months of January and
February and below the 16 to the left is found Saturday which forms the key from
March to the end of the year.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is-
1. A perpetual calendar, consisting of an inner disc revolvable within an encircling
rim and bearing on the one side the months of the year and on the other the days
of the month, in combination with the days of the week upon the faces of the ring
and numbers inscribed upon the peripheral rim by which the key to the use of the
instrument is found, as hereinbefore described and illustrated in the drawings.
2. The herein-described perpetual calendar, consisting of a disc fitted to revolve
within a ring both having names and figures inscribed thereon for inter-reference,
as described, the calendar being mounted as a watch-trinket or charm, as set
forth.
Dated th
FAL
1001
E. A. CRESSON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.