Chinese Traditional Time System
The traditional time system is the time system in ancient China. Shi-ke and G-P system are typical systems which were used in ancient China for over 2000 years. Shi-ke describes the time according to the readings on a time meter, such as sundial, ruler of the water clock, clock, etc. G-P system is describes the time according to a predetermined signal, such as a drum, bell, gong, or bioclock.
Shi-ke
The shi-ke system is derived from time measurement. The shis are the scales on the sundial, and the kes are the scales on the sundial[1] or ruler of the water clock.[2]
Dual-hour/shi
Shis are 12 milestones in a day, which are used to stamp the time. The 12 shis are: midnight, crowing, dawn, sunrise, breakfast, ante, noon, post, dinner, sunset, dusk, and quieting. The earthly branches are used to name the 12 shis: zish, choush, yinsh, maosh, chensh, sish, wush, weish, shensh, yoush, xush, haish. The time between shis is two hours. After Song dynasty, shis are used to indicate the dual-hours before/after 12 shis too.
Centiday/ke
The time between two scales is a centiday or 14.4 minutes(i.e.14'24"). When the shi scales and centiday scales are marked on the ruler of the water clock, the shi scales are smaller, and be called as snicks. The time between the scales and snicks is the multiple of 2.4 minutes (2 minutes 24 seconds),[3] which is the common factor time between centiday scale and shi scale.
Shi-ke
The shis and kes are matched to describe the time. There're two expression mode:
- shi first mode. Before Tang dynasty, in the time expression, the kes are counting from each shi:
"shi","1 ke","2 ke","3 ke","4 ke","5 ke","6 ke","7 ke","8 ke". Such as"Xush 1 ke(i.e.20:09:36)" - shi nominal mode. After Song dynasty, in the time expression, the kes are counting from an hour before each shi:
"initial","1 ke, a.","2 ke, a.","3 ke, a.","4 ke, a.","shi","1 ke, p.","2 ke, p.","3 ke, p.","4 ke, p.". Such as"3 ke, a.wush(i.e.11:31:12)".
G-P system
| G-P | HMS | Shike1 | Shike2 | %day |
|---|---|---|---|---|
| 3:00 | 0:00 | 00:00 | 115:00 | 0.0% |
| 3:25 | 1:00 | 04:10 | 00:00 | 4.2% |
| 3:50 | 2:00 | 10:00 | 05:00 | 8.3% |
| 4:00 | 2:24 | 12:00 | 07:00 | 10.0% |
| 4:15 | 3:00 | 14:30 | 10:00 | 12.5% |
| 4:40 | 4:00 | 20:00 | 15:00 | 16.7% |
| 5:00 | 4:48 | 24:00 | 19:00 | 20.0% |
| 5:05 | 5:00 | 24:50 | 20:00 | 20.8% |
| 5:30 | 6:00 | 30:00 | 25:00 | 25.0% |
| 5:55 | 7:00 | 34:10 | 30:00 | 29.2% |
| 6:00 | 7:12 | 35:00 | 31:00 | 30.0% |
| 6:20 | 8:00 | 40:00 | 35:00 | 33.3% |
| 6:45 | 9:00 | 44:30 | 40:00 | 37.5% |
| 7:00 | 9:36 | 46:00 | 43:00 | 40.0% |
| 7:10 | 10:00 | 50:00 | 45:00 | 41.7% |
| 7:35 | 11:00 | 54:50 | 50:00 | 45.8% |
| 8:00 | 12:00 | 60:00 | 55:00 | 50.0% |
| 8:25 | 13:00 | 64:10 | 60:00 | 54.2% |
| 8:50 | 14:00 | 70:00 | 65:00 | 58.3% |
| 9:00 | 14:24 | 72:00 | 67:00 | 60.0% |
| 9:15 | 15:00 | 74:30 | 70:00 | 62.5% |
| 9:40 | 16:00 | 80:00 | 75:00 | 66.7% |
| 10:00 | 16:48 | 84:00 | 79:00 | 70.0% |
| 10:05 | 17:00 | 84:50 | 80:00 | 70.8% |
| 10:30 | 18:00 | 90:00 | 85:00 | 75.0% |
| 10:55 | 19:00 | 94:10 | 90:00 | 79.2% |
| 1:00 | 19:12 | 95:00 | 91:00 | 80.0% |
| 1:20 | 20:00 | 100:00 | 95:00 | 83.3% |
| 1:45 | 21:00 | 104:30 | 100:00 | 87.5% |
| 2:00 | 21:36 | 107:00 | 103:00 | 90.0% |
| 2:10 | 22:00 | 110:00 | 105:00 | 91.7% |
| 2:35 | 23:00 | 114:50 | 110:00 | 95.8% |
Deciday/gong
The gongs are the drum/gong time signal. The time signal is drum beat by the Bell and Drum Tower in the city, and gong beat by watchman in the town. The first gong is at 1 ke, a.xush.
The time between gong beats is 2.4 hours or a deciday.
The 5 gongs in the night are named by number, such as yig, erg, sang, sig, and wug. The 5 gongs in daytime are morn, ante, noon, post, and eve.
Point
The points are the bell time signal. The time signal is released by the Bell and Drum Tower or temples. There're 60 points within a day.
- In modern oral Chinese, point is used to express the o'clock.
Gong-point
Gong and point are matched to describe the time in the night.
- The night length is inconsistent during a year. It's 60 centiday in the winter solstice, and 40 centiday in the summer solstice. So the start of night is from 0 to 1 gong. In practice, the start are postponed for 0.5 centiday after each 9 days from the winter solstice to the summer solstice, and moved up for 0.5 centiday after each 9 days from summer solstice to the winter solstice.
Minute/fen
For calendar convenience, a centiday or point is divided into 100 parts. In general, 1% point has a greater effect. i.e. a point = 100 minutes, a centiday = 60 minutes. Refer to the ISO8601,
- the time formua of shi-ke system may be sk:mm, such as
53:00(3 ke, a.wush). - The formula of G-P system may be g:ps, such as
5:30(wug 3 point).
See also
Notes
- ↑ F. Richard Stephenson and David A. Green; Historical supernovae and their remnants, Oxford University Press, Oxford (2002), pages 15-16. ISBN 0-19-850766-6
- ↑ According to the Shuowen Jiezi from Xu Shen, “漏以铜壶盛水，刻节，昼夜百刻。” Translation: “The water clock holds the water in the copper pot, and marks the scale on the rule. there're 100 scales which represents a day.”
- ↑ 600 is the LCM of 100 and 24, so the time between centiday and shi scale may be 1⁄6, 1⁄3, 1⁄2, 2⁄3, or 5⁄6 major ke. The 1⁄6 major ke is the common factor
References
- Ronan, Colin p 247-250 in Walker, Ch. ed.: Astronomy before the telescope. Brit. Museum P., UK (1999). ISBN 0-7141-2733-7