direkt zum Inhalt springen

direkt zum Hauptnavigationsmenü

Sie sind hier

TU Berlin

Inhalt des Dokuments

One Inflow Clepsydra Model with dual Time-Signal Generator for the Striking Clepsydra

M. H. Nam, Y. H. Hahn, J. H. Lee, D. Y. Han and M. H. Seo (Kon-Kuk University, Seoul)

The Striking Clepsydra or Automatic Striking Water-Clock Jagyoknu (隊羲顽) made in 1434 by King Sejong was well-known for its elaborate ball-operated time annunciating jackwork mechanisms. The details of the clepsydra are described on the Sejong Shillock (�@宗槨�, Veritable Records of King Sejong) Chapter 65. The clepsydra consists of four water-supply vessels (�戒�) different in sizes, two water-receiving vessels (捂戒�) of the same size and two floating indicator-rods (釨逊). At the top of each water-receiving vessel, ball-rack mechanisms (洧�) are erected to generate dual time-signal digitally for annunciating twelve double-hours and five night-watches and their five points. Needham and his colleagues proposed two inflow clepsydra model in 1965 and revised by Nam in 1985. The model consists of two clepsydras, one for twelve double-hours and the other for the night-watches and has been widely accepted. We have found recently that there were mistakes in translating the passages in the Sejong Shillock on the clepsydral arrangement and ball-rack mechanism.

In this paper one inflow clepsydra model with dual time-signal generator is proposed for the Striking Clepsydra after re-examining the records, various literatures and the surviving parts of the New Striking Water Clock which is the duplication of the Striking Clepsydra in 1536. The four water-supply vessels were rearranged in the order of height; reservoir, compensating vessel, constant-level tank and receptacle. This arrangement was influenced by medieval Chinese overflow method. Two water-receiving tanks were used alternately as inflow clepsydra every other day, in which floating indicator-rod rose up. On the surface of the indicator-rod, marks for twelve double-hours and one hundred intervals were graduated. Dual timing signals are generated when the floating indicator-rod dislodges 12 (twelve double hours) and 25 (five night-watches and their five points) small bronze balls in the ball-racks corresponding to their time indices.

Finally, a new A/D mechanism proposed and revised in this paper shows the validity of the model and is believed to make an era in horological history.

Zusatzinformationen / Extras


Schnellnavigation zur Seite über Nummerneingabe