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Publication numberUS458970 A
Publication typeGrant
Publication dateSep 1, 1891
Filing dateApr 3, 1891
Publication numberUS 458970 A, US 458970A, US-A-458970, US458970 A, US458970A
InventorsHenry Fitch
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 458970 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

(No Model.) 2 Sheets-Sheet 1.


LL-JIJ @www 2. t e e h S s t e e h S 2 H C T T.. n... H M e d 0 M 0 N II\ CALENDAR.

No. 458,970. Patented Sept. l, 1891.

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SPECIFICATION forming part of Letters Patent No. 458,970, dated September 1, 1891.

Application led April 3,1891. Serial No. 387,510. (No model.)

To @ZZ whom it may concern.-

Be it known that I, HENRY FITCH, a citizen of the United States, residing at Lawrenceburg, in the county of Dearborn, State of Indiana, have invented certain new and useful Improvements in Calendars; and Ihereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, whereinro Figure l is a view of a set of annual calendars, seven in number, adapted for the ordinary years, each calendar commencing with a different day of the week. Fig. 2 is a similar view of a set of annual calendars, seven I 5 in number, adapted for leap-years, each calendar commencing with a diierent day of the Week; and Fig. 3 is aview of an index wherein there is placed opposite each year a symbol indicating the annual calendar for use in dezo termining or ascertaining any date of said year.

Like symbols refer to like matters wherever they occur.

My invention relates to that class of calen- 2 5 dars intended for use throughout a series of years or for determining or ascertaining the day of the week on which any date will fall or has fallen, commonly termed perpetual calendars. This class of calendars as heretofore commonly constructed have either necessitated the use of an unsightly and un usual arrangement of dates in transverse and vertical columns, calculated to confuse the ordinary user, and thus lead to error, or else 3 5 have been constructed with shifting weekdays and year indicators requiring manipula tion from time to time, and therefore subject to error from lack of proper adjustment or from accidental displacement of the slides.

4o The object of my present invention is the production of a simple and efcient calendar of the class above specied which shall present no unusual or irregular arrangement of dates or general complicated appearance to confuse the unscientific user and which shall not contain shifting or adjustable parts liable to be displaced, and thus lead to error. W`hile in the calculation of time down to the present era years of different lengths have been used 5o and the errors arisinO- have been corrected by the elimination of days or periods, so that we have two common calendars-viz., the old style or Julian calendar and the new style or Gregorian-yet for all purposes of a general calendar there are in reality but two classeslirst, those years which are termed ordinary years, which contain fifty-two (52) full weeks and a day and in which the year begins and ends on the same day of the week, and, second, those years termed leap years, which 6o contain an extra day and end on the day of the week succeeding that on which they commenced. It therefore follows that a series of annual calendars composed of two sets of seven each-that is, two sets, one for the ordinary 6; years and one for the leap or eXtra-day years, the separate calendars of each set commencing with a different day of the week-*must contain one calendar appropriate for any given year, whether Julian or Gregorian. 7o

My invention therefore, generally stated, consists, first, in a general year-index wherein opposite each year is placed a symbol indicative of the character of the year (whether ordinary or leap year) and the day of the week on which the year commenced or will commence, (as the case may be,) whereby reference may be readily made to any annual calendar which has the given characteristics, and, secondly, in the combination, with a se- 8o ries of annual calendars composed of two sets, the calendars in each set commencing with a different day of the week and having distinctive symbols, of a year-index wherein opposite each year is placed the symbol corrc- 8 5 spending with the annual calendar adapted to the said year.

I will now proceed to describe my invention more specifically, so that othersl skilled in the art to which it appertains may apply 9c the same.

In Figure l of the drawings are shown sufiicient of each of a set of annual calendars for ordinary years to clearly indicate the char* acter of each calendar, so that others skilled 9 5 in the art can produce the calendar. Said calendars are shown in their order of arrange ment, one for each day of the week with which the year commences, and the whole set (for ordinary years) is indicated by the letter a, to which is added the number corresponding to the day of the week, so that n.' indicates ICO the annual calendar wherein theyear ccmmences and ends on Sunday, or the first day of the week. ctzindicates the calendar wherein the year commences and ends on Monday, or the second day of the week, and so on, a3 c4 a5 a a7 corresponding to the respective days of the Week on which the several calendars begin and end. l

In Fig. 2 of the drawings are in like manner representeda set of calendars corresponding to leap-years, also arranged in their order of daily succession, the class as awhole indicated by the letter B and the separate calendars indicated by adding the number corresponding to the day of the week on which the calendar commences. Thus B indicates the calendar for leap-year commencing on Sunday, B2 that commencing on Monday, and so on, B3 B4 B5 B6 B7 to the calendar commencing on Saturday. In addition to the ordinary calendar there may, if desired, be marked or printed on the margin of each annual calendar the years to which said calendar is applicable, as shown at the left hand of the drawings, Figs. 1 and 2, and while this is of some Value in assuring the user of the correctness of his selection, yet it is not a material feature of the present invention.

In Fig. 3 is illustrated an index to be used in conjunction with the annual calendars herein specified or their equivalents. Said index may commence with any given year and terminate with any given year, though for purposes of convenience, and, as fully illustrating the principle involved, I have conn-V menced with the year 1101 (twelfth century) and ended with 2000, (twentieth century,) and have double-lined (transversely) the columnheadings and arranged therein at the proper places the remaining centuries from the first (O. S.) to the twenty-eighth, (N. S.,) adding a third column at the year 1583 where the newstyle or Gregorian calendar commences.

Referring now to the index, Fig. 3, it will be observed that for the Julian calendar (or years prior to 1583)it consists of two vertical columns, over the first of which is the word Yearj and in said column the years are noted in succession, and over the second column is the word Old, and in said column are the symbols c3 a* a5 B6 d a2, the., refer- -ring to the proper calendar of the hereinbefore-described series for the year opposite which the respective symbol is placed. After the year 1582, or at the time of commencement of the Gregorian calendar, (1583,) a third parallel column is added, and at the top thereof the word New is placed to indicate the change. At this point the old manner of reckoning may be dropped, if desired, and the index reduced to its former condition of two parallel columns; but I prefer to retain the old style and add the new style, instead of substituting one for the other. In this said third column I place opposite the successive years from and inclusive of 1583 the appropriate symbols a7 B c3 a4 a5 Bs, duc., each referring to that calendar of the hereinbeforespecified series, which is the correct calendar for the given year, all as clearly shown in the drawings.

In using the calendar hereinbefore described in order to ascertain the day of the week upon which any given date will fall in any given year all that is necessary is to first find the year in its position on the index, Fig. 3, then note the symbol placed opposite said year in the parallel column, which symbol will indicate the correct calendar of the series for said year, and in the'calendar thus indicated theV given date willbefound under its properweekdayheading. Forinstance,itisknownthat the siege of Jerusalem ended on July 13, A. D. 70. On examining theheadings of the index, Fig. 3, we find that the year of the first century falls in the same column with the eighth and fifteenth centuries, and the proper calendar therefor is the same as for the corresponding year of the eighth and fifteenth centuries, or, in other words, is the same calender as for the year 14:70, which is indicated by the symbol d2. On turning to the calendar marked co2 we find that July 13 falls on Friday, and thus ascertain that July 13, A. D. 70, on which the siege of Jerusalem ended, was Friday. As a second illustration of the use of the hereindescribed calendar, take the inauguration of President Benjamin I-Iarrison, March 4, 1889. On examining the index, Fig. 3, we find in the parallel column opposite that year the symbol a3, and on referring to the calendar marked a3 we iind that March I fell on Monday.

In constructing the calendar I prefer, for sake of clearness, to use red or an equivalent bright color for the symbols referring to the old style (or prior to 1583) and black for the symbols referring to the new style, (or for 1583 and later,) especially if both old and new style references are retained after 1583 5 but the same forms no material part of the present invention, as any color or colors may beused, and after 1583 the old-style references can be omitted or used at will, as hereinbefore specified; and, further, though the symbols a 0.2 B B2, dsc., have been used by me in illustrating the invention and indicating the character of the calendar and the day of the week on which it commences, and such symbols will be recognized as having apeculiar fitness therefor, yet any other characters or symbols may be substituted therefor without departing from the spirit of my invention.

Having thus described my invention, `what Iclaim, and desire to secure by Letters Patent, 1s-

1. A perpetual-calendar index consisting of parallel columns, one of said columns containing year-dates and the other a series of symbols arranged opposite the year -dates and indicating the day of the week on which each year commences and the character of the year, whether ordinary or leap year, substantially as and for the purpose specified.

2. The combination, in a perpetual calen- IOL IIO

(lar, of two sets of annual calendars, one set corresponding to ordinary years and the other i to leap-years, the respective calendars of each set commencing with a different day of the 5 Week, and an index therefor, consisting of parallel columns, one column containing the years and the othera series of symbols which indicate the day of the Week on which each year commences and thecharacterof the year, lo Whether ordinary 0r leap year, whereby the correct calendar for each year may be selected, substantially as and for the purposes speciiied.

In testimony whereof I aix my signature, in 15 presence of two witnesses, this 3d day of April,

HENRY FITCH. Witnesses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4813707 *Mar 11, 1988Mar 21, 1989Habib Mohammed KPerpetual calendar
US4863193 *Jun 23, 1988Sep 5, 1989Khosrow KeshaniMulti-year calendar
Cooperative ClassificationB42D5/04