Our Calendar Part 6

The Declaration of Independence was signed July 4, 1776. On what day of the week did it occur? We have then 1776 4 = 444; 1776 + 444 = 2220; 2220 7 = 317, remainder 1. Then 7 - 1 = 6, therefore F and G are the dominical letters for 1776, G for January and February, and F for the rest of the year. Now reading from F to G, the letter for July, we have F Sunday, G Monday; hence July commenced on Monday, and the fourth was Thursday. On what day of the week did Lee surrender to Grant, which occurred on April 9th, 1865? We have then 1865 4 = 466+; 1865 + 466 = 2331; 2331 7 = 333, remainder 0. Then 1 - 0 = 1; therefore, A being the first letter, is dominical letter for 1865. Now reading from A to G, the letter for April, we have A Sunday, B Monday, C Tuesday, etc. Hence April commenced on Sat.u.r.day, and the 9th was Sunday.

Benjamin Harrison was inaugurated President of the United States on Monday, March 4, 1889. On what day of the week will the 4th of March fall in 1989? We have then 1989 4 = 497+; 1989 + 497 = 2486; 2486 7 = 355, remainder 1. Then 2 - 1 = 1; therefore, A being the first letter, is dominical letter for 1989. Now, reading from A to D, the letter for March, we have A Sunday, B Monday, C Tuesday, and D Wednesday; hence March will commence on Wednesday, and the 4th will fall on Sat.u.r.day. Columbus landed on the island of San Salvador on Friday, October 12, 1492. On what day of the month and on what day of the week will the four hundredth anniversary fall in 1892?

The day of the month on which Columbus landed is, of course, the day to be observed in commemoration of that event. The Julian calendar, which was then in use throughout Europe, and the very best that had ever been given to the world, made the year too long by more than eleven minutes. Those eleven minutes a year had acc.u.mulated, from the council of Nice, in 325, to the discovery of America, in 1492, to nine days, so that the civil year was nine days behind the true or solar time; that is, when the Earth, in her annual revolution, had arrived at that point of the ecliptic coinciding with the 21st of October, the civil year, according to the Julian calendar, was the 12th.

Now, to restore the coincidence, the nine days must be dropped, or suppressed, calling what was erroneously called the 12th of October, the 21st. Since the Julian calendar was corrected by Gregory, in 1582, we have so intercalated as to retain, very nearly, the coincidence of the solar and the civil year. It has already been shown in Chapter III, (q. v.) that in the Gregorian calendar, the cycle which restores the coincidence of the day of the month and the day of the week, is completed in 400 years; so that after 400 years, events will again transpire in the same order, on the same day of the week. Now, as Columbus landed on Friday, October 21st, 1492, so Friday, October 21st, 1892, is the day of the month and also the day of the week to be observed in commemoration of that event. We have then 1892 4 = 473; 1892 + 473 = 2365; 2365 7 = 337, remainder 6. Then 8 - 6 = 2; therefore, B and C are dominical letters for 1892, C for January and February, and B for the rest of the year. Now, reading from B to A, the letter for October, we have B Sunday, C Monday, etc. Hence October will commence on Sat.u.r.day and the 21st will be Friday.

Although there was an error of thirteen days in the Julian calendar when it was reformed by Gregory, in 1582, there was a correction made of only ten days. There was still an error of three days from the time of Julius Caesar to the Council of Nice, which remained uncorrected. Gregory restored the vernal equinox to the 21st of March, its date at the meeting of that council, not to the place it occupied in the time of Caesar, namely, the 24th of March. Had he done so it would now fall on the 24th, by adopting the Gregorian rule of intercalation. Appendix H.

If desirable calculations may be made in both Old and New Styles from the year of our Lord 300. There is no perceptible discrepancy in the calendars, however, until the close of the 4th century, when it amounts to nearly one day, reckoned in round numbers one day. Now in order to make the calculation, proceed according to rule already given for finding the dominical letter, and for New Style take the remainders after dividing by seven from the numbers in the following table:

From 400 to 500 From 4 or 11 " 500 " 600 " 5 " 12 " 600 " 700 " 6 " 13 " 700 " 900 " 7 " 900 " 1000 " 1 " 8 " 1000 " 1100 " 2 " 9 " 1100 " 1300 " 3 " 10 " 1300 " 1400 " 4 " 11 " 1400 " 1500 " 5 " 12 " 1500 " 1700 " 6 " 13

It will be found by calculation that from the year

400 to 500 the discrepancy is 1 day 500 " 600 " " " 2 "

600 " 700 " " " 3 "

700 " 900 " " " 4 "

900 " 1000 " " " 5 "

1000 " 1100 " " " 6 "

1100 " 1300 " " " 7 "

1300 " 1400 " " " 8 "

1400 " 1500 " " " 9 "

1500 " 1700 " " " 10 "

Hence the necessity, in reforming the calendar in 1582, of suppressing ten days. (See table on 59th page.) On what day of the week did January commence in 450? We have then 450 4 = 112+; 450 + 112 = 562; 562 7 = 80, remainder 2. Then 3 - 2 = 1; therefore, A being the first letter, is dominical letter for 450, Old Style, and January commenced on Sunday. For New Style we have 4 - 2 = 2; therefore, B being the second letter, is dominical letter for the year 450. Now reading from B to A, the letter for January, we have B Sunday, C Monday, D Tuesday, etc.

Hence, January commenced on Sat.u.r.day. Old Style makes Sunday the first day; New Style makes Sat.u.r.day the first and Sunday the second. On what day of the week did January commence in the year 1250? We have then 1250 4 = 312+; 1250 + 312 = 1562; 1562 7 = 223, remainder 1. Then 3 - 1 = 2; therefore, B being the second letter, is dominical letter for the year 1250, Old Style. Now, reading from B to A, the letter for January, we have B Sunday, C Monday, etc. Hence January commenced on Sat.u.r.day. B is also dominical letter, New Style; for we take the remainder after dividing by 7, from the same number.

As both Old and New Styles have the same dominical letter, so both make January to commence on the same day of the week; but Old Style, during this century, is seven days behind the true time, so that when it is the first day of January by the Old, it is the eighth by the New.

Vernal equinox in the time of Numa, about 700 B. C.

It is here seen by the errors of the Julian Calendar the Vernal Equinox is made to occur three days earlier every 400 years, so that in 1582 it fell on the 11th instead of the 21st of March. 18

17

16

15

14

13

12

11 By suppressing 10 d

Hou

Hou

By the Gregorian rule of intercalation the coincidence of years.

March 24, 46 B. C.

23 1 A. D.

Restored 22 100 " "

by 21 300 " "

Julius 20 400 " "

Caesar, 19 Vernal 500 " "

equinox 46 B. C., at the 600 " "

Council to the of 800 " "

Nice, place it 325 900 " "

A. D. occupied 1000 " "

in the 1200 " "

time of 1300 " "

Numa. 1400 " "

ays, Coincidence 0 Restored in 1600 " "

rs behind time, 18 6 in advance. 1700 " "

" " 12 12 " " 1800 " "

" " 6 18 " " 1900 " "

Coincidence 0 Restored. 2000 " "

rs behind time, 18 6 in advance. 2100 " "

" " 12 12 " " 2200 " "

" " 6 18 " " 2300 " "

Coincidence 0 Restored. 2400 " "

the solar and civil year is restored very nearly every 400

Appendix I.