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Man-nen Jimeisho - The Zenith of Hisashige's Career

The Man-nen Jimeisho (Man-nen Dokei) chronometer, completed in 1851, showcases Hisashige's clock-making expertise.

Hisashige opens a shop in Kyoto, the Kiko-do, where his passion for invention intensifies.

Man-nen Jimeisho
Reference:
Man-nen Jimeisho [property of Toshiba Corporation; on loan to the National Science Museum]

Having attained further renown with the success of his revolutionary Mujin-to lamp, Hisashige Tanaka decided to expand operations. He opened a store called Kiko-do in the Shijo-Karasuma quarter of Kyoto, where he launched full-scale production of the Mujin-to lamp and pocket candlestand. Although Hisashige was already a successful inventor, his enthusiasm for invention increased and he continued to develop his skills as a clockmaker. Kiko-do advertising from this time showcases what might fairly be described as Hisashige's masterworks — the Man-nen Jimeisho chronometer, Shumisen-gi; model of the Buddhist universe, and the Unryusui pump. This lineup truly represented the zenith of his career.

Japan's first planetarium: a model of the Buddhist universe built at the request of a senior Buddhist monk.

Japan's first planetarium, the Shumisen-gi; model of Mount Sumeru, was created by Hisashige in 1850 at the request of a senior member of the Buddhist clergy. It was designed to illustrate the cosmology of Indian Buddhism, which places Mount Sumeru at the center of the Buddhist universe. According to the advertisement, the device allows observation of the advance of time over the course of the year in the movement of the constellations, the progress of the four seasons and sunrise and sunset.

In its conceptualization and meticulous craftsmanship, this piece perfectly exemplifies Hisashige's knowledge and creative flair. During this period, Hisashige also produced many other ingenious mechanical timepieces including the Makura-dokei; pillow clock, and Taiko-dokei; drum clock. His skills and ideas as a clockmaker were approaching their apogee, and they would soon all be channeled into construction of the Man-nen Jimeisho, the finest traditional Japanese-style clock ever built.

Leaflet for the Kiko-do
Shumisen-gi

Reference:
(left) Leaflet for the Kiko-do [National Science Museum]
(right) Shumisen-gi [property of Ohashi Watch; on loan to the Seiko Institute of Horology]

The Man-nen Jimeisho perpetual clock exhibited in Toshiba Science Museum is a replica. It's mechanical motion can be observed. The original Man-nen Jimeisho is exhibited in the National Science Museum (motion observation not available).

The inscription inside Man-nen Jimeisho reads "tanaka oumi [i.e., hisashige], resident of kyoto."
Reference:
The inscription inside Man-nen Jimeisho reads "tanaka oumi [i.e., hisashige], resident of kyoto."

The long-running, multifunctional Man-nen Jimeisho (Man-nen Dokei) chronometer: the crowning achievement of traditional Japanese clockmaking.

The Man-nen Jimeisho chronometer showed time as never before.

Leaflet on Man-nen Jimeisho
Leaflet on Man-nen Jimeisho [National Science Museum]

Imagine a device measuring 60 cm high and weighing 38 kg, with six different clocks built into six different faces. All the clocks move synchronously when wound, and are powered by a pair of clockwork mechanisms housed in the base, which is sumptuously decorated with cloisonné. Estimates show that the clock will run for a year on a single winding. On the top are two metal spheres, representing the sun and moon, which follow paths in accordance with the seasonal diurnal motion of those two heavenly bodies viewed from Kyoto.

Such are the elements integrated into Hisashige's greatest masterpiece, the Man-nen Jimeisho, which he built in the years 1850-51. Today it is owned by Toshiba, which has loaned it to the National Science Museum for exhibition. A detailed description of the functions of the clock and planetarium is provided in the clock's user's manual, Banzai Jimeisho Rokumen Yoho Zu.

The Man-nen Jimeisho user's manual, the Banzai Jimeisho Rokumen Yoho Zu

Reference:
The Man-nen Jimeisho user's manual, the Banzai Jimeisho Rokumen Yoho Zu
[National Science Museum]

The ultimate combination of functionality and ornamentation. How it all works.

FACE 1

FACE 1

The outer dial and hand show the hour according to the traditional Japanese method of telling time. The inner dial and hand show the exact season according to the traditional oriental division of the year into twenty-four parts.

FACE 2

FACE 2

Here you supply the date, according to the old Japanese calendar, of each of the twenty-four seasonal divisions for the year in question. The dial can be tilted forward, allowing you to peek inside while adjusting the chime with the knob on the right.

FACE 3

FACE 3

There are two dials and hands, for showing the day of the week and for adjusting the chime, respectively.

FACE 4

FACE 4

This face indicates the date according to the traditional oriental sexagenary cycle (a combination of one of the lunar ten calendar signs and one of the twelve signs of the Chinese zodiac).

FACE 5

FACE 5

The outer dial shows the day of the month according to the old Japanese calendar. The silver and black globe in the middle revolves to indicate the waxing and waning of the moon.

FACE 6

FACE 6

Embedded here is a French (or, according to one theory, Swiss) pocket watch, whose escapement mechanism is linked with all the other clocks so that all six faces work together.

Note:
Face 1 refers to the clock face that shows the hour according to the traditional Japanese method. Faces 2 to 6 follow clockwise.

PLANETARIUM

PLANETARIUM

Above a detailed map of Japan, two small spheres mimic the diurnal motion of the sun and the moon synchronized with the time. The two spheres vary in height with the season.

THE CLOISONNÉ WORK

The sides of the base in which the clockwork is embedded are decorated with four motifs in cloisonné: a tortoise, a rooster, a drum, and a rabbit. The cloisonné work, with filigree in brass and silver, is absolutely exquisite; it is easy to imagine the effort and expense that went into it.

FACE 1
FACE 1
FACE 2
FACE 2
FACE 3
FACE 3
FACE 4
FACE 4
FACE 5
FACE 5
FACE 6
FACE 6

POWER SOURCE

POWER SOURCE

The cloisonné decorated base conceals a pair of brass double clockwork mechanisms that power the clock. The mechanism at the back drives the hands. Wind it up once, and the Man-nen Jimeisho should run for roughly a year. The mechanism at the front is for the chime.

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