Chapter XXX: Appendix: B

CONCORDANCE OF ROMAN AND MODERN HOURS,

FOR THE YEAR OF ROME 699 (55 B.C.) AND FOR THE LATITUDE OF PARIS.

Spring Equinox March 23, 5 o’clock, p.m.

Summer Solstice June 25, 5 o’clock, p.m.

Autumnal Equinox September 26, 3 o’clock, a.m.

Winter Solstice December 23, 7 o’clock, p.m.

The dates are referred to the Julian style.

The Roman hours are reckoned from sunset and sunrise.

The modern hours are given in true solar time.

The Roman hours are given at the head of the columns, in Roman numerals. The modern hours are in ordinary numerals. Two examples will explain the use of the Table.

_Division of the Night on the 16th of August._--To obtain it, we seek the date in the indicating column on the left, entitled NIGHTS. We conclude from the line opposite: at 7h. 11m., sunset, beginning of the first hour and of the first watch; at 9h. 36m., end of the first watch and beginning of the second; at 12h. 0m. it is midnight, the second watch ends, the third begins; at 2h. 24m., end of the third watch, beginning of the fourth; at 4h. 49m. the sun rises, and the fourth watch ends.

_Division of the Day on the 16th of August._--We seek the date in the indicating column to the right, entitled DAYS. We conclude from the line opposite: at 4h, 49m., sunrise, beginning of the first hour; the third hour ends at 8h. 25m.; the sixth, hour at noon; the ninth at 3h. 35m.; at 7h. 11m, the sun sets.

At the summer solstice, each watch embraces two of our hours; in the winter solstice, it embraces four.

--------------------------------------------------------
| 1ST WATCH | 2ND WATCH |
|-------------------|-----------------|
NIGHTS | I II III IV V VI |
-----------------|/ \ / \ / \ / \ / \ / \|
|H M H M H M H M H M H M H|
June 25 |8 1 8 41 9 20 10 0 10 40 11 20 12|
July 5|June 15|7 58 8 39 9 19 9 59 10 40 11 20 12|
July 16|June 4|7 51 8 33 9 14 9 56 10 37 11 19 12|
July 26|May 25|7 41 8 41 9 7 9 51 10 34 11 17 12|
| | |
Aug. 5|May 15|7 28 8 13 8 59 9 44 10 29 11 15 12|
Aug. 16|May 4|7 11 8 0 8 48 9 36 10 24 11 12 12|
Aug. 26|April 24|6 55 7 46 8 37 9 27 10 18 11 9 12|
| | |
Sept. 5|April 13|6 37 7 31 8 25 9 19 10 13 11 6 12|
Sept. 16|April 2|6 18 7 15 8 12 9 9 10 6 11 3 12|
Sept. 26|Mar. 23|6 0 7 0 8 0 9 0 10 0 11 0 12|
| | |
Oct. 6|Mar. 12|5 42 6 45 7 48 8 51 9 54 10 57 12|
Oct. 16|Mar. 2|5 23 6 29 7 35 8 41 9 47 10 54 12|
Oct. 25|Feb. 21|5 6 6 15 7 24 8 33 9 42 10 51 12|
| | |
Nov. 4|Feb. 11|4 49 6 1 7 13 8 25 9 36 10 48 12|
Nov. 14|Feb. 1|4 33 5 48 7 2 8 17 9 31 10 46 12|
Nov. 24|Jan. 22|4 19 5 36 6 58 8 10 9 27 10 43 12|
| | |
Dec. 3|Jan. 12|4 9 5 28 6 46 8 5 9 23 10 42 12|
Dec. 13|Jan. 2|4 2 5 22 6 41 8 1 9 21 10 40 12|
December 23 |3 59 5 20 6 40 8 0 9 20 10 40 12|
-----------------|\ / \ / \ / \ / \ / \ /|
NIGHTS | I II III IV V VI |
-------------------------------------------------------+

+---------------------------------------------------------+
| 3RD WATCH | 4TH WATCH | |
|-----------------|---------------------| |
| VII VIII IX X XI XII | DAYS |
|/ \ / \ / \ / \ / \ / \|-----------------|
| M H M H M H M H M H M H M | |
| 0 0 40 1 20 2 0 2 40 3 19 3 59 | December 23 |
| 0 0 40 1 20 2 1 2 41 3 21 4 2 |Jan. 1|Dec. 14|
| 0 0 41 1 23 2 4 2 46 3 27 4 9 |Jan. 11|Dec. 4|
| 0 0 43 1 26 2 9 2 53 3 36 4 19 |Jan. 21|Nov. 25|
| | |
| 0 0 45 1 31 2 16 3 1 3 47 4 32 |Jan. 31|Nov. 15|
| 0 0 48 1 36 2 24 3 12 4 0 4 49 |Feb. 10|Nov. 5|
| 0 0 51 1 42 2 33 3 23 4 14 5 5 |Feb. 20|Oct. 26|
| | |
| 0 0 54 1 47 2 41 3 35 4 29 5 23 |Mar. 2|Oct. 16|
| 0 0 57 1 54 2 51 3 48 4 45 5 42 |Mar. 13|Oct. 6|
| 0 1 0 2 0 3 0 4 0 5 0 6 0 |Mar. 23|Sept. 26|
| | |
| 0 1 3 2 6 3 9 4 12 5 15 6 18 |April 2|Sept. 15|
| 0 1 6 2 13 3 19 4 25 5 31 6 37 |April 13|Sept. 5|
| 0 1 9 2 18 3 27 4 36 5 45 6 54 |April 23|Aug. 26|
| | |
| 0 1 12 2 24 3 35 4 47 5 59 7 11 |May 3|Aug. 16|
| 0 1 14 2 29 3 43 4 58 6 12 7 27 |May 14|Aug. 6|
| 0 1 17 2 33 3 50 5 7 6 24 7 41 |May 24|July 27|
| | |
| 0 1 18 2 37 3 55 5 14 6 32 7 51 |June 3|July 17|
| 0 1 20 2 39 3 59 5 19 6 38 7 58 |June 14|July 6|
| 0 1 20 2 40 4 0 5 20 6 40 8 1 | June 25 |
|\ / \ / \ / \ / \ / \ /|-----------------|
| VII VIII IX X XI XII | DAYS |
|----------------------------------------------------------