calendar clock;
box
- Museum number
- 1891,0617.26
- Description
-
Tidal Calendar Mechanism
Silver circular box on bronze stand with three legs; in the side is an aperture in which are successively visible the twelve calendrical animals (all separate pieces), the top has 6 small apertures showing the date (on the outer part) and the phases of the moon and times of flood, full and ebb tide (at the centre); a bird and a tortoise form the handles by which the mechanism is advanced.
- Production date
- 1800-1890
- Dimensions
-
Diameter: 108 millimetres (max)
-
Height: 103 millimetres (max)
- $Inscriptions
-
- Curator's comments
- Information from Ms KAMIYAMA Megumi of Seiko Museum, Oct. 2020:
As the traditional Japanese calendar was based on a lunar cycle, the time of high tide varied. This mechanism contains interconnected gears such that, when the month and day are set in the outer pair of apertures, one can read off the phases of the moon (circular aperture at centre) and the start times of three tidal stages (rectangular apertures, with inscriptions beside): Sashi サシ = Flood tide; Michi ミチ = Full tide; Hiki ヒキ = Ebb tide. This information was essential to merchants engaged in maritime trade in Edo-period Japan. The tidal times are given in the form '4-4', indicating '4th hour and 4 parts' or '7-4', indicating '7th hour and 4 parts'. The following article includes an Edo-period tidal table, explaining the times indicated:
https://www.jstage.jst.go.jp/article/engankaiyo/25/2/25_191/_pdf
There is a similar mechanism in the Seiko Museum, Tokyo, described as ‘Netsuke clock with tidal indications’.
セイコーミュージアム 銀座 神山氏: 日本の旧暦(太陽太陰暦)は月齢を元にしたサイクルなので、日付で潮の干満がわかりました。月と日を表記している歯車と、中央の時刻表示の歯車は連動している。中央の三つの小さな窓は、潮汐時計と思われます。各窓は以下の現象が始まる時刻を表示しています。サシ＝差し潮＝上げ潮;ミチ＝満潮;ヒキ＝引き潮。ミチの「四四」は「四ツ四分」、ヒキの「七四」は「七ツ四分」と思われます。以下の論文に江戸時代の潮汐表が掲載されているので、時刻の読み方などご参考ください。
https://www.jstage.jst.go.jp/article/engankaiyo/25/2/25_191/_pdf
当館所蔵品にも似たようなものがあり、当館では「汐見計付根付日時計」という名称です。
- Location
- On display (G93/dc6/sG)
- Exhibition history
-
Exhibited:
2023 April - BM, Mitsubishi Corporation Japanese Galleries
- Condition
- Latest: 2 (May 2015)
- Acquisition date
- 1891
- Department
- Britain, Europe and Prehistory
- Registration number
- 1891,0617.26
