Timekeeping in Edo Period Japan

In the Edo or Tokugawa Period town dwellers were notified of the time of day by the sounding of the local temple bell; a system undoubtedly used for several centuries previously.  Night watchmen sounded the hours of the night with clapping boards or by beating drums.  The predominantly agricultural society had little use for mechanical clocks.

However, mechanical clocks were used in Edo castles to keep time and thus regulate some of the daily activities of the castle complex, such as the opening of the gates.  Also, some communities within cities, such as Edo (Tokyo), had a building with a mechanical clock and employed a certain number of watchmen to keep the clock running and announce the hours to the community.  Similar practises were probably widespread throughout other major cities.

In the absence of documentary evidence, we can only speculate on which social groups were most likely to own domestic clocks in Tokugawa Japan, and on the uses they had for them.  Clocks were owned by daimyos, some of whom had extensive collections, and probably by high-ranking samurai.  Wadokei are often referred to as “Daimyo Clocks”.

In Tokugawa Japan, as in Europe during the 16th and 17th centuries, only men of status owned mechanical clocks, although status may have depended less on wealth in Japan than in Europe.

The later shaku-dokei, small simple hanging clocks which hung unobtrusively on a wooden pillar of a house, must have immediately appealed to the characteristically sober taste of the Japanese. The lively feeling that the to-and-fro movement of the foliot previously imparted to clocks was preserved either by having the short pendulum swing in front of the clock movement or by adding some accent to the balance wheel to make its alternating motion more evident.  A charmingly simple automaton visible over the front plate was often added to shaku-dokei, particularly those with a balance wheel.  It was mounted on the extended arbor of the crown wheel, which protruded through the front plate, and turned around with this wheel.  Such automatons took one of two forms; some consisted of a short hand, which pointed toward an engraved chapter ring.  Such a dial served no time-telling purpose, and its numerals may have conveyed some feeling or message of outlandish novelty.  The other type of automaton more closely matched the floral decoration of the front plate and seems more traditionally Japanese.  It consisted of a butterfly continuously turning against a floral background.

Japanese household clocks convey the impression that they were mere mechanical curiosities.  Such a feeling may relate to their time­keeping inaccuracy and the consequent need for repeated adjustment, and probably accounts for claims by some Japanese researchers that household clocks served no timekeeping purpose, instead playing the role of toys.  But this interpretation may be tinged by a modern, Western-like concern for timekeeping accuracy that did not apply to Japan in the 1800s.

The daimyos who owned wadokei may have used mechanical clocks to time official events at their castles, as in Edo. They may have also used clocks as simple mechanical curiosities, examples of snobbish novelty, or even as status symbols in a society that relegated merchants to a status lower than any other group, except the outcasts. As the 19th century advanced, clocks may have played an increasingly important role as timekeeping devices, although never as important as in the West.