For Edo Period Japan, knowing the precise time was more a status symbol than an everyday necessity.
"When one could clearly make out the back of one's outstretched hand, that was around 'akemutsu,' or slightly before sunrise," explained Midori Kamiguchi, 56, curator of Daimyo Dokei Museum.
"In an era when people woke up with the sunrise and retired at sundown, that was about all people needed to know."
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