KANSHUTEI.

Inquire · Offered by Peter Harrington

Seiyo jiki teikokuhan ("How to Read a Western Clock"). Pocket-sized for easy reference, this work allows for quick conversion between the seasonal clock used in early modern Japan and the standardized clocks used in Europe and America; an important skill as trade with the Dutch steadily increased throughout the early 19th century. We trace no institutional copies outside Japan.In the Edo period, time was measured using a variable system; as the length of each day changed with the seasons the length of each hour would also change. Clocks were invented that could automatically compensate for these variations. Over time, there grew a need to convert between this system and the fixed time clocks used by Europeans who visited Japan to trade on the island of Dejima.This work shows the reader how Japanese hours map on to the Western clock throughout the year. Each page shows a different month, with the six hours of the day marked in red and the six hours of the night marked in black.It is undated but is mentioned directly by Sato Issai (1771-1859), a Confucian scholar and proponent of modernized clocks, in his Yosei sokujiki ki ("On Western Timekeeping", 1838). We have have handled one other copy, with taller margins, Kanshutei's name and romanized initials in the preface, and an additional circular symbol on each clock face. No priority has been established.

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