Mechanism of 'Man-nen dokei,' a Historic Perpetual Chronometer Part 1: Celestial Globe and Japanese Traditional Clock

摘要

The "Man-nen dokei," that literally means a clock that works for ten thousand years, is a historic perpetual chronometer that was made by Hisashige TANAKA at 1851. It is one of the national important cultural properties. Recently, it has been disassembled and restored in a national project, so we investigated the mechanism of the Man-nen dokei in cooperation with the project. This paper shows the mechanism of the celestial globe and the Japanese traditional clock which is the main part of the clock.