page_title: Japanese clock
section_title: History
hierarchical_section_title: Japanese clock / History
caption_attribution_description: English: Exhibit in the National Museum of Nature and Science, Tokyo, Japan. Photography was permitted in the museum without restriction.
context_page_description: A Japanese clock is a mechanical clock that has been made to tell traditional Japanese time, a system in which daytime and nighttime are always divided into six periods whose lengths consequently change with the season. Mechanical clocks were introduced into Japan by Jesuit missionaries or Dutch merchants. These clocks were of the lantern clock design, typically made of brass or iron, and used the relatively primitive verge and foliot escapement. Tokugawa Ieyasu owned a lantern clock of European manufacture.
  Neither the pendulum nor the balance spring were in use among European clocks of the period, and as such they were not included among the technologies available to the Japanese clockmakers at the start of the isolationist period in Japanese history, which began in 1641. The isolationist period meant that Japanese clockmakers would have to find their own way without significant further inputs from Western developments in clockmaking. Nevertheless, the Japanese clockmakers showed considerable ingenuity in adapting the European mechanical clock technology to the needs of traditional Japanese timekeeping.
context_section_description: Clocks have existed in Japan since the mid-7th century AD in the form of water clocks. The Nihon Shoki states that Emperor Tenchi made a water clock, or rōkoku (漏刻, literally "leaking" + "cutting, measuring"), in 660 and 671. These clocks were used for another 800 years until the arrival of Christianity in Japan in the 16th century.
  Christian missionaries were among the first to introduce Japan to Western-styled clocks. Francis Xavier, a Spanish Society of Jesus saint and missionary, gave Ouchi Yoshitaka, a daimyō of the Sengoku period, a mechanical clock in 1551.  Other missionaries and embassies soon followed, with a mechanized clock being given to Oda Nobunaga in 1569 and Toyotomi Hideyoshi in 1571 by Papal envoys, and two clocks given to Tokugawa Ieyasu, one in 1606 by a missionary and one in 1611 by a Portuguese envoy. The oldest surviving western clock in Japan dates back to 1612; it was given to Shōgun Ieyasu by the viceroy of Mexico (then New Spain).
   Near the turn of the 17th century, the first Western-styled, mechanical clocks were produced by Japanese natives. Tsuda Sukezaemon is reported to have made a mechanical clock in 1598 after he had examined and repaired many imported clocks on his own. Japanese clock making was facilitated in the 17th century by missionaries living in Japan. Christian missionaries were the first to instruct the Japanese on clockmaking in the Amakusa islands around the turn of the 17th century.
  The Edo period (1603–1868) saw the adaptation of Western techniques to form a unique method of clock making in Japan. A double escapement was designed by Japanese clockmakers in order to develop a clock that followed the uneven, traditional Japanese time schedule. These clocks, called wadokei, were built with different methods in order to follow the temporal hour system (futei jiho 不定時法). The foliots of the clocks have several divisions allowing the user to set a relatively accurate rate. Foliot-controlled clocks, despite being widely replaced in Europe by circular-balanced clocks, were utilized in Japan due to their adaptability to the temporal hour system. Constant weight and dial adjustments led Japanese clock makers to develop the nichō-tenpu tokei (二挺天府時計) or "two-bar governor clock",  around 1780. The weights in the nichō-tempu tokei were automatically set for the correct time of day or night with the use of two governors or balances, called tenpu (天府).
  A key component of the development of Japanese clocks was the publication of Hosokawa Hanzo's Karakuri Zui in 1796, in which he explains production methods of clocks in the first volume, and karakuri ningyō (絡繰人形) or "mechanical dolls" in the second and third volumes. The volume on clockmaking contained highly detailed instructions for the production of a weight-driven, striking clock with a verge escapement controlled by a foliot. Relatively high literacy rates and an enthusiastic, book-lending society contributed greatly to the work's widespread readership.
  The production and complexity of clocks reached its peak with Tanaka Hisashige's man-nen dokei (万年時計) or myriad year clock.  This has six faces that feature a western clock, a lunar phase indicator, the oriental zodiac, a Japanese temporal clock, the ancient Japanese 24-phase division indicator, and an indicator for the day of the week. The clock was said to be able to run for a year on a single winding.
  After the Meiji Restoration in 1868, Japan eventually abolished the use of its temporal hour system. The Meiji Cabinet issued Ordinance No. 453 in 1872 which switched Japan from the lunar calendar to the western, solar calendar. The switch led to the decline of wadokei and the emergence of a western-styled clock industry in Japan.
caption: Tanaka Hisashige's man-nen dokei (万年時計). Completed in 1851.
exif: {"Image ImageDescription": "", "Image Make": "SONY", "Image Model": "DSC-RX100", "Image XResolution": "350", "Image YResolution": "350", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "DSC-RX100 v1.00", "Image DateTime": "2014:03:29 12:25:34", "Image Artist": "Picasa", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "292", "Image PrintIM": "[80, 114, 105, 110, 116, 73, 77, 0, 48, 51, 48, 48, 0, 0, 2, 0, 2, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0]", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "15710", "Thumbnail JPEGInterchangeFormatLength": "5804", "EXIF ExposureTime": "1/8", "EXIF FNumber": "63/10", "EXIF ExposureProgram": "Aperture Priority", "EXIF ISOSpeedRatings": "3200", "EXIF SensitivityType": "Recommended Exposure Index", "EXIF RecommendedExposureIndex": "3200", "EXIF ExifVersion": "0230", "EXIF DateTimeOriginal": "2013:09:04 23:53:01", "EXIF DateTimeDigitized": "2013:09:04 23:53:01", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "2", "EXIF BrightnessValue": "173/320", "EXIF ExposureBiasValue": "1", "EXIF MaxApertureValue": "217/128", "EXIF MeteringMode": "Pattern", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "52/5", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "3547", "EXIF ExifImageLength": "5080", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "5472", "Interoperability RelatedImageLength": "3648", "EXIF InteroperabilityOffset": "15562", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF FocalLengthIn35mmFilm": "28", "EXIF SceneCaptureType": "Standard", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal", "EXIF ImageUniqueID": "c06f304017a6e21e2902d9b96c793817", "EXIF LensSpecification": "[52/5, 371/10, 9/5, 49/10]"}