The Myriad-Year Clock
57cm in height and decorated with cloisonné, lacquer work and mother-of-pearl, this large standing spring-driven click was made in 1851 by Hisashige Tanaka (1799-1881), a prominent engineer during the late Tokugawa era to the early Meiji period, after spending nearly a rear on the project.The six dials at the top features Western and Japanese time dials, as well as weekly, monthly and zodiac settings. On the upper part is an astronomical dial mechanism and the old Japanese temporal hour system of employing the time of sunrise and sunset in particula indicate Tanaka's high level of mechanical expertise and deep knowledge of nature science. Japan was capable of smoothly adapting Western science and technology in the Meiji period owing to the foundation laid down during the Edo period. The Myriad-Year Clock is a historical monument symbolising Tanaka's contribution in bridging science and technology from the Edo period to Meiji period.
Mining in the Edo period
Call the "Land of Gold" by Marco Polo, Japan was blessed with mineral resources, such as gold and silver, and forest resources that were converted to fuel, and was considered to be one of the world's leading mining countries since before the Edo Period. The Edo government actively promoted the mining industry, establishing mines throughout the country. Copper production was the highest in the world, and products were distributed internationally via Nagasaki.
Koban Iroage Technique (Redying Techniques of Koban)
This is acolor development technique which draws out the gold color in gold and silver dlloy and has proven to be moredurable than planting. During the Edo period, the ratio of gold to silver in the koban varied from year to year, leading to the possibillity of some obans and kobans haveing a stronger silver appearance than other. This redying technique was performed to alleciate this situation. It is said that the use of this method is cofirmed in ancient Inca artwork. According to Japanese tradition, however, this method is believed ti have been passed down as the secert medhod employed by the methalsmith "Goto Shirobei-Ke" and was used in Obanza and Kinza (oban and gold mint). Literatures use the, irotsuke (dying), and later iroage (redying). With this method, the koban is coated with a dye and heated, the silver portion is extracted from the gold and silver surface, and the remaining gold is recrystallized to form a gold-enriched layer.
Development and popularization of arithmetic
The Edo Period boasted a long stable period of peace that facilitated the birth of a society in which commoners, too, could learn "reading, writing, and abacus calculation" at terakoya (private elementary schools). The study of Wasan (traditional Japanese mathematics), once confined to scholars and certain members of the warrior class, also spread among commoners due to its practical application in study and business. Mathematics schools emerged in the academic field, and the ensuing intellectual competition led to the development of a high level body of mathematics comparative to Western mathematics.
Calculation Boards and "Juuki Calculation Method" (5 volumes)
The abacus has been popularly used by many people in modern times, however most wazan scholars, used the "sangi" or counting rods, a calculation tool used since ancient times. Under this method, counting rods are arranged and calculated according to the decimal system. THe wooden or paper board used to maneuver the counting rods is called the calculation board. Lines are drawn along the matrix lines and the counting rods are placed inside the squares. This is somewhat a roundabout method of calculation, but has proven to be a more sophisticated method of calculation (processing of equations of higher degree) than the abacus.
Wazan books for commoners
By the late Edo period, simple wazan knowledge spread among the people, appearing in numerous literatures. A wide variety of wazan were introduced ranging from textbooks in temple schools, daily usage encyclopedia, abacus manuals, geometric progression, interest calculation to games such an magic square.
ZinkokiNational Museum of Nature and Science
Astronomy and surveying
The Japanese characters for "survey" come from a Chinese expression meaning "Gauge the sky, weight the earth." In the Edo Period, surveying techniques spread as practical skill as Western astronomical and surveying knowledge blended with traditional Japanese surveying techniques. The civil engineering, flood control, and miniing projects that proliferated in the Edo Period were only possible because of the widespread diffusion of surveying techniques.
Globes
In the West, the terrestrial globe and astronomical sphere were used equally. In addition to these, the kontengi (astrolabe) imported from Chiana was also used and possessed by scholars of astronomical calendars and rampeki daimyo (Hollandaophile daimyo). The first terrestrial globe and astronomical sphere to in Japan is said have been made by the Tokugawa government astronomer Harumi Shibukawa in 1695 and the actual globes (an important cultural property) are currently owned by the National Museum of Nature and Science. This terrestrial globe, which illustrates the map in Mateo Rich form, is identical to the one made by Harumi Shibukawa.
Middle size quadrant
In order to accomplish his purpose of surverying the whole nation of Japan and to measure the distance of 1 degree latitude, Tadataka Ino needed to make accurate astronomical observations throughout the country. The quadrant was one of the surverying equipments used to measure the position of the stars. It was made with reference to the Reidaigishoushi (1674) under the order of master Shigetomi Hazama. There were two quadrants: the large-size quadrant measuring 6 shaku ( or approximately 180 cm) in radius and the middle-size quadrant measuring 3.8 shaku ( or approximately 115 cm) in radius. The middle-size quadrant was used for the nationwide surverying project.
RyoteishaNational Museum of Nature and Science
Ryoteisha
The ryoteizha (measuring wheel) is a surverying equipment which measures the distance between two points using a wheel mechanis, that indicates the distance traveled by multiplying the driving wheel perimeter by the number of wheel rotations. There were several surverying equipments during Tadataka Ino's time, but the ryoteisha was the most commonly used tool for measuring distances. Judging from the poor condition of the roads and the small size of the dricing wheel, it is doubtful that the measurements were accurate. It is thought that this tool was merely used with the aim to have the surveying conditions recognized those conserned.
Ryochi Zusetsu (2 volumes)National Museum of Nature and Science
Ryochi Zusetsu (2 volumes)
This is technical book on surveying written by Hironaga Kai of the Hitachi Kasama domain, a disciple of Hasegawa of the Seki school. This book was published before the arrival of Commedore Perry and many Western surveying tools were accurately engineered based on a mathematical theory. Wazan scholars began to research the theory and usage of these tools, thus arriving with the publication of numberous technical books on surveying as this book. This book explained in detail the basic choken method which utilized the existing surveying tools made of wood. It also advised readers in the advertisements at the end of the book to only use the sophisticated Western octants after studying the funamentals.
Complete set drawing tools
Drawing tools used is surveying during the Edo period differed slightly depending on the school and year, but were basically tools shich indicated the direction and distance of a location on a smaller scale drawing. Directions were indicated by angles inscribed on the bundono kane (a combination of a circular protractor and ruler), circular protractor, semicircular protractor and quarter circle protractor. The reduced-size drawings were made using the compass and ruler. Like the hoshibiki and subiki which were used to draw dotted lines, pen type writing tools from the West were already utillized during the Edo period. Circular protractor, quarter-circular protractor (or sextant), semi-circular protractor, hoshibiki, compass, needle.
Kenban compass
The kenban compass was the most commonly used surveying instrument during the Edo period. This tool is used by forming similar triangle with the target objects on the kenban compass. The kenban compass could be easily made with wood and enabled the measurement of the height of trees and mountains when used horizontally. Moreover, the relatively easy calculation process of similar triangles allowed this tool to be used until the beginning of the Meiji period. There are recordings that the height of Mr. Fuji was measured using this method.
HonsoNational Museum of Nature and Science
Honzo Komoku Keimo
Honzogaku (empirical scientific study of plants and animals) was acknowledged as medical and medicinal science in early Edo priod. The honzo study tectbook Honzo Komoku introduced 60 types of medicine in 16 classes, systematically categorized according to animal, plant or mineral. This categorization style greatly influenced the development of honzo in Japan. In 1627, the first Japanese book, Zusetsu Honzo was published. With the influence of Dutch science in the following years and continued study of honzo, the Honzo Komoku Keimo (48 volumes) was publishied by Tanzan Ono incorporating animals and plants of Japan to the Chinese based honzo book Honzo Komoku. This book is the fourth edition which was edited and publishied by Minonokami Choshin Okabe (Kishi Wada domain, Izumi Prefecture) aiming to develop honzogaku.
Yamato Honzo (Japanese Herbal Medicine)
With reference to the honzo study textbook Honzo Komoku (1802), this book introduces approximately 300 diagrams based on a seminal study of over 1362 species of animals, plants and minerals. It explains in details the Japanese and Chinese names of the species, as well as the regional origin, form and its effectiveness. This is considered to be epoch making literature marking the first step in Japanese herbal medicine. THe Yamato Honzo has significant historical value as the pioneer of natural history during the Edo period.
Butsurui Hinshitsu
This book is a collection of materials from five medicine exhibitions organized by Gennai Hiraga and Motoo Tamura between 1757 and 1762. Categorized according to the Honzo Komoku, the book focuses on explanations on specimens collected both in Japan and abroda. There are over 360 specimens, including a specimen of a lizard preserved in liquid obtained from rapeki daimyo acquaintances. The book explains cultivation method of ginseng and sugar canes proposed by Gennai, proving to be a epoch making book for honzogaku in the Edo period.
Unkonshi
The Unkonshi was named after the phrase "cluds are generated from rocks". It contains information on habitat, history and features of over 2000 tyoes of unique rocks and stone tools, fossils and minerals which were collected by Sekitei Kiuchi during his lifetime. Born in 1724, Kiuchi worked with the local magistrate of the Zeze domain until he retired in his 20's. He studied honzogaku with Keian Tsushima in Kyoto, and became one the central figures in the Kansai cultural salon of that time. He actively attended exhibits throughout the country including Kyoto to collect specimens and gather information.
Yacura clock (lantern clocks)
There are various types of wadokei or Japanese clocks : kake dokei (wall clocks), Yagura dokei (lantern clocks), dai dokei (grandfather clocks), makura dokei (pillow clocks) and shaku-dokei (ruler clocks). Among these, the Yagura dokei (lantern clocks), the most typical Japanese clock in form, are clocks on high pyramid stands. There are different speed control devices among wadokei such as the single foliot escapment, double foliot escapment, circulare balance and pendulum weight, with the single foliot escapment generally being the oldest device. The early period single foliot wadokei had to be adjusted daily with 6 weights at sunrise and 6 weights at sunset. The Nicho Tenpu or double fokiot mechanism is a clock unique to Japan invented in the mid-Edo period aiming to solve the labor intense aspect of the former wadokei. With the Nicho Tenpu device, the two foliots regulators, one for daytime (top part) and one for nighttime (bottom part) with each having 6 weights. The two foliots automatically switched from one to the other at sunrise and sunset. The night time foliot. According to the Japanese time system based on sunrise and sunset, nighttime is considered to be two hours shorter than daytime on average.
