JAPANESE WALL CLOCK ‘HASHIRA DOKEI’ Ca. 1780 Japan
JAPANESE WALL CLOCK ‘HASHIRA DOKEI’
The weight-driven two-train movement is of 24-hour duration with rope wind. The going train has a double verge escapement, one for the day and the other for the night, switching automatically. The time keeping is adjusted by moving small weights, which are suspended in notches on the foliots, closer or further away from the centre. The striking train is regulated by a countwheel and indicates the hours and half hours. It starts with 9 and runs back to 4, while the half hour is indicated by one and two strokes alternatingly. The movement also has a spring-driven alarm set by a pin in a central alarm disc behind the hand.
The dial has a chapter ring with Chinese zodiac symbols and Japanese numerals for the indication of the time by an elaborately pierced blued-steel hand. Below the chapter ring is a date aperture.
The wooden case is painted in red and has gauzed panels on two sides and a glazed window at the front, showing the clock itself. The movement’s case is made of brass. The front is engraved depicting chrysanthemum, leaf and scroll motifs. It is surmounted by a double foliot and a substantial bell.
Duration 24 hours
Height 33 cm.
Width 13 cm.
Depth 14 cm.
– N.H.N. Mody, Japanese clocks, Rutland, 1967.
– W. Brandes, Alte Japanische Uhren. Braunschweig, 1976.
The Japanese timekeeping was very different from timekeeping in the western world. Instead of the hour as a fixed value the length of an hour in Japan, toki in Japanese, varies according to the length of day and night. Both day and night are divided into 6 toki, spread over the period from sunrise to sunset and from sunset to sunrise. In summer the days are longer than the nights and therefore a toki during the day in longer than one during the night. In winter this is the other way around. For this reason Japanese clocks have chapter rings with movable chapters, so that de length of the toki can be modified. There are also clocks with a fixed chapter ring. In this case the clock’s beat rate changes by moving the weights on the foliot to slow down or accelerate the clock. This we mainly see in older clocks. The numerals on the clocks run from 9 to 4 (The numbers 1-3 were not used for religious reasons). The only numeral that is fixed is 9 o’clock, our 12 noon. The count ran backwards because the earliest Japanese artificial timekeepers used the burning of incense to count down the time. Dawn and dusk were therefore both marked as the sixth hour in the Japanese timekeeping system. Each toki, 12 in total, also had its own sign of the zodiac which are depicted on the chapter ring, around the hour numerals.