Science and Technology in the Edo Period, Japan National Museum of Nature and Science

As civilization has evolved, curiosity has taken the form of a meticulous pursuit of knowledge. For instance, rough stone tools eventually were developed into precision machinery. The rapid progress of science has made our lives more convenient and comfortable; simultaneously creating new problems such as air and water pollution. This exhibit showcases some Japanese inventions from the Edo period onwards. As you can see from these inventions, Japanese culture maintains its unique identity and its close communion with nature, while at the same time having interaction with foreign cultures. An understanding of science and technology in Japan can help guide our future.

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 particular 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 symbolizing 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.

Complete Map of Gold and Silver Mining in Sashuu
This manuscript scroll depicts what it was like inside the mine starting with the entrance of the mine, the mininng process, measuring prospecting volume, and unloading the findings. There are detailed illustrations of ore dressing, transportation, and the process of scouring to minting of kobans (old Japanese gold coins) inside the magistrate’s office. Such reference materials exist for other mines, but none are as elaborate as elaborate as that of the Sado Gold Mine. This give evidence that the Sado Gold Mine has continued to operate as one of the world’s largest gold and silver mines since the beginning of mining history in Heian Period to the present.

Shinzan Mitate Hidensho (The secret of finding new mines)
For a mining speculator or engineer, the most important responsibility is the exploration and discovery of mines. Mining engineers were allowed to freely travel throughout the country in and out of checkpoints. In the Edo period, many mining engineer groups were ordered by the goveenment and feudal domains to search for and excavate mines throughout Japan. This bool summarizes the know how and technology of mining ecploration during this period and explains the difference in surface mountain color among gold, silver and coppoer mines as well as the different types and distinctions between mountain conditions (geography, wether, landscape), minerals and ores.

Kingindonamari Kensa Hidensho (Secrets of Examining Gold, Silver, Copper and Lead)
One of the essential knowledge and skills required of a mining engineer is examining and determining whether the mined minerals have worthy and profitable metal contents such as gold, silver and copper. Lead was an indispensable metal for amalgam or the refining process of gald, lead and copper from mineral. The production of lead was relatively large in Japan to other metals, and thus the mercury amalgam method was not used in Japan as it was in the gold, silver and copper mines in Western Europe and South America. The book also explains how to make the lead amalgam furnace and other hurnaces, summarizing the refinery technology used during this time.

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.

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.

Hatsubi Calculation Method
This is he only publication issued by the wazan scholar Tkkazu Seki (? – 1708) during his lifetime. This book provides answers to the 15 questions proposed by Kazuyuki Sawaguchi in his book Kokin Sanpoki (1671). Over the 25 years since the publication of Kinkoki, the complexity of wazan problems far exceeded the realm of elementary arithmetic where promlems could easily be solved using the abacus. For problems shich in present days would use algebraic equations, Siki applied Fukudai which was developed from the traditional Chinese calculation method Tengen jyutsu.

Calculation board and Juuki calculation method
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.

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.

Yamato Shichyoreki (Japaneses seven-day calendar)
This astronomical calendar introduced to Japan from China, also included the daily positions of the sun, moon and the fice stars, but ciased to be used by the Muromachi period. In the Edo period, Shibukawa initiated the calendar reform (jyukyo kaireki). This display is one of the early lunar calendar calculated in 1617. This was in print from 1685 until the end of the Edo period.

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.

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.

Surveying the land with the help of an alidade – a sighting device or pointer for determining directions or measuring angles.

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.

Middle size quadrant
In order to accomplish his purpose of surveying 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 surveying 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 surveying project.

The ryoteizha (measuring wheel) is a surveying 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 surveying 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.

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.

Transition from herbalism to natural history
Japan acquired much valuable knowledge about animals, plants, and minerals from China. By the Edo Period, surveys of domestic resources were well underway, and cultivation and selective breeding of a wide variety of plants became common. Consequently, many bools on agriculture and herbolism were published and, with the inclusion of and comparison with Western knowledge, herbalism developed into modern natural history.

Development of herbalism
Herbalism is a discipline to classify useful natural products, mainly drugs. When the Ming Dynasty’s “Primordial Line” was imported in the beginning of the 17th century, it came to classify what is in nature as plants, animals, minerals. In that process, the herbalists began to notice the difference between nature in China and Japan, and started to investigate domestic resources. Mr. Ekiken Kaibara wrote “Yamato Honzo” which handled domestic natural products.

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.

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.

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.

Development into modern natural science
In the 18th century, Western natural materials and books related to natural science came in through Nagasaki Prefecture. Under the influence, herbalism has spread beyond usefulness and uselessness to a natural science widely targeting nature in general. In the 19th century, a large number of scientific flora and fauna charts were created under sharp nature observation eyes. Linnaeus’s plant classification method was also introduced, and an illustration based on this was also made.

Yosan Hiroku
Silk was Imported from China as a luxury textile and silk worm breeding, silk reeling and textile manufacturing was conducted domestically even before the Edo period. With the beginning of the Edo period, product manufacturing took off on a nationwide scale, and local special goods were made in various regions throughout Japan. With this , sericulture technology made significant progress, with over 100 technical books being published during the Edo period. Volume one of this book discusses the origin of sericulture, naming, type of silkworm, mulberry tree plantation, silkworm breedint tools. Volume two explains the actual breeding process of silkworms from birth, bed cleaning, larvae separation to spinning of the silk. Volume three goes into the production of raw cotton and cotton threads. The author of this book, Mrikuni Uegaki, ran a silk breeding farm in Tajima, and worked to improve silk breeding techniques by incorporating methods form other areas. This book is considered a comprehensive book of silkworm breeding technology.

The Yosan Hiroku was exported abroad by the Siebold. During this time, Europe was struggling with a countermeasure against silkworm disease which had spread. This book was included among the items presented by Siebold to the King of Holland. It was translated into French and later published in Paris and Italy in 1848, making a significant contribution to the silkworm breeding industry in Europe. This is a well known example of Japanese technology from the Edo period having an impact overseas in areas other than painting and performing arts.

Nogyo Zensho
The first edition of this book, published in 1697, consisted of 10 volumes and 1 appendix volume. It was written by Yasusada Miyazaki who served for the Kyushu Koroda domain based on his findings from forty years of experiments and observations. Using the Jo Kokei’s Nosei Zensho (Ming Dynasty) as he model, this book aimed to compile Japanese adricultural technology into one book. Beginning with the second edition in 1786, this book continued to be the standard book on agriculture in Japan for a long time. Subsequent to Volume 1 (10 chapters) on Introduction to Agriculture (farming, seeds, soil, fetilizers, etc.), the series consists of Gogoku (volume 2, 19 types), Sanso (volume 6, 11 types), Shimoku (volume 7, 4 types), Kamoku (volume 8, 17 types), Shomuku (volume 9, 15 types, and Medicine (volume 10, 22 types).

Shokugaku Keigen
The Shokugaku Keigen by the Dutch scholar Yoan Udagawa, is the first book on Western modern botany introduced in Japan as well as the West. In the foreword of the book, Kenbo Mitsukuri writes that this bool differs from honzogaku and Western botany in the past, stressing the importance of studying the law and process of natural science as a academic study, and not merely categorizing. It comprises of three volumes with the first volume discussing plant classification, and the shape and physiology of roots, stem and leaves. The second volume looks at flowers and fruits, and the reproduction and DNA mechanism of seeds. The third volume talks about plant fermentation and decomposition and includes diagrams.

Medicine in the Edo period
From the middle of the Edo Period, Rangaku (Dutch studies in Western medicine), grew increasingly popular. Even some traditional Kanpoh-i (Chinese herbalists) actively enlisted the cooperation of Dutch scholars in studying human anatomy as medical practitioners attempted to integrate empirical Western medicine. Thus, this period saw the creation of a distinctly Japanese medical traditional through the skillful blending of traditional Chinese and Western medical traditions.

Origins in Chinese medicine
Japanese medicine drew from Chinese medicine in the Sui-Tang transition (the end of the 6th century to the end of the 7th century). “Qi” (life energy), and the structure of the body is expressed by “Internal organs” and “Meridian”, and its state is interpreted in the right middle of ancient China such as “Yin Yang”, “Five-row”, and “False”. Until the rise of Ranchaku, this was the central medical thought of Japan.

Acupuncture and moxibustion tools
Acupuncture and moxibustion were introduced from China long ago, dating as far back as 701, but it was not familiar to the people as a form of remedy until the Edo period. Acupuncture became popular with the introduction of the Japanese uchibari and kudabari, and gained the highest status of kengyo from the Tokugawa government. Moxibustion was at first used in comnination with acupuncture, but it began to be used as a health fitness tool and later spread in the Edo period as the burning mugworts were placed directly on the pressure points on the back, arms and legs.

A keiraku (meridian) doll used for training in acupuncture. The doll is marked with 14 energy paths and pressure points. The keiraku doll originates from the Chinese dojin doll. The dojin doll is scarved with energy paths and pressure points, and is devised that when the acupuncture needle hits the pressure points, mercury seeps out. According to records, these dolls were brought to Japan during the Muromachi period, but Japan began making their own keiraku dolls with the spread of acupuncture therapy in the beginning of the Edo perod and they became widely sued in general practices.

Oriental Medicine
In the early Edo period, internal medicine, surgery and acupuncture emerged. Internal medicine was based on medical study during Chinese medieval gold period (late 13th century ~ late 14th century). In the middle Edo period, there are Kojin people who tried to return to empirical Chinese ancient medicine. Ancient surgeons conducted human dissections using translations of Western medicine books, leading the emergence of the Ran (Dutch) study in the late Edo period. The main branch of Edo medicine was known as Oriental medicine, and continues as Japan’s unique style of medicine today.

Medicine box
During the Edo period, it was common practice for doctors to make house calls. Doctors purchased herbal medicine from herbal pharmacists and dispensed their own prescription, Doctors stored the herbal medicine in a medicine cabinet having many drawers. When making house calls, doctors carried small amounts of the herbal medicine in small paper bags in their medicine box and made the prescriptions. In rampo medicine, scales were used to make up the prescription, but in traditional Chinese kampo medicine ingredients were measured using a spoon. This is because kampo medicine used nourishing hebs based on experience that were not as strong, immediately effective as rampo medicine, but had long-kasting effectiveness.

Mokkotsu (wooden frame dolls)
Crafttsmen were commissioned to make mokkotsu dolls which accurately modeled the bone structure of humans for the study of osteopathy. Tecords show that 9 mokkotsu dolls for made during the Edo period, but only 4 are extant. There are two types of mokkotsu dolls, dollsmade by the osteopath Ryuetsu Hoshino and those by Bunken Kagami. The Okuda mokkotsu dolls, believed to have taken 20 months to finish, were made by the craftsman Bo Ikeuchi in 1819 under the order of Banri Okuda, an apprentice of Bunken Kagami. The Okuda mokkotsu was donated to the Nagoya Medical Museum in 1822 and a picture of its exhibitions at a medical convention is in the Owari Meisho Zue.

Rise of Ran school
In the middle of Edo period, Western anatomy and surgical books became visible to people, the difference between Western and Oriental medicine became clear. Human body dissection began, and Mr Ryosuke Maeno and Mr Genpaku Sugita Translated the Dutch anatomy to publish “Dissolution new book”. Dutch studies started with this, and Dutch books such as medicine, astronomy, and military science were translated in various places. “Narutaki Juku” was also held in the suburbs of Nagasaki.”

Ontleedkundig Tafelen
The Kaitai Shinsho is a Japanese translation of the Ontleedkundig Taflen written in Dutch by the German, Adam Kulmus. This is the first book on anatomy, and the diagrams of the dissected human body is supplemented with explanations. Ryotaku Maeno obtained this book from Kogyu Yoshino, an interpreter who studied Dutch in Nagasaki. Genbaku Sugita (Kohama domain) who studied Dutch medicine was impressed by the accuracy of this book where he compared the text with the actual dissection procedure with Tyotaku Maeno and decided to translated it into Japanese.

Kaitai Shinsyo
Astounded by the accuracy of the diagram in rekation to the dissected organs, Genbaku Sugita and Ryotaku Maeno who both witness dissection of executed prisoners decidedto translate the Western dissection book Talleben which was publish in 1774. The Kaitai Shinsho is the first transkated western book in Japan. The publication of the translated book not only influenced medical science with the emergence of ramgaku, but also had a substantial impact the westernization of Japanese modern culture. The first editions consisted of five books, one foreword volume and four text volume. Tadatake Odano who drew the instructional diagrams was a disciple of Gennai Hiraga and is the pioneer of Akita Ranga painting. Although Ryotaku Maeno’s is not mentioned in this book, the strong cencorship of prohibited religions made advertisement of the book very difficult.

Vaccination tools
Vaccination was carried out by pouring out the vaccine, which was stored in a glass container for portability, onto a gkass slab, making an incision in the patient’s arm and implanting the vaccine into the cut. As vaccination from the West spread throughout the country in the end of the Tokugawa period, Dutch medicine became the mainstream medicine practiced in Japan, replacing Chinese kampo medicine. This trend continued onto the Meiji period.

Skills of the masters
Rationality and practicality were esteemed qualities in Edo Period Japan, and so emphasis was placed on fields of study beneficial to society. In contrast, people at this time enjoyed games and unusual things, resulting int the high regard in which Wabi (subtlety), Sabi (elegant simplicity) were held and the emergence of such particularly Japanese aesthetic sensibilities as Iki (stylish) and Inase (dashing). These helped cultivate Japan’s unique artisanship culture as craftsmen in a diversity of fields, from artware and craftware to livingware and toys, evolved exquisite skills.

Watch and Karakuri
In the mechanical clock transmitted from the West in the middle of the 16th century, a variety of watches were created to adapt to the indeterminate time law used in Japan. Mechanical mechanisms were made not only for practical items such as Japanese clocks but also for the enjoyment of Karakuri dolls and stage devices.

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.

Hanging Clock
The main body of the clock, with the nicho-tenpu mechanism, is put on a stand for hanging that is decorated with a beautiful design in mother-of-pearl inlay. The clock’s main body adopts the most standard design for wadokei, which is a design of box-shape, or hakama-foshi, style, with its lower part open. On four sides of the body, a so-called arabesque design of franadilla is embossed. And for the bell-fixing screw, not a gardenia shape but a shape called warabi-te (fern rolled on itself) is adopted. THe machinery of the clock is made of iron and can be basically divided into jiho (the ticking mechanism) and daho (the bell-ringing mechanism). The train of gears (the number of rows) of this clock is less by one compared with a turret clock. Generally, it is considered that all of hanging clocks, turret clock, and pedestal clocks have the same clock body, and they are recognized by their names that show diggerence in the shape of mounting. By taking a look at the mechanism, we can tell that it needed to be hanged at some higher position, on a post or a wall, to allow enough distance for the plumb bob to come down. That’s how we know this one was manufactured as a hanging clock.

Makura dokei (pillow clock)
The makura dokei (pillow clock) is a spring-driven, standing bracket clock with its brass gears and springs inside a sandaiwood case. The speed of most makura dokei (pillow clocks) is regukated by a circular bakance. These clocks had adjustable dials with varying scales to accommodate the Japanese temporal time system. Some of these clocks were very valuable with the brass pieces were dicorated with pillars and gold inlays, and were sometimes referred to as the daimyo clock. The makura dokei (pillpw clock) has brass gears and uses a pendulum as the speed regulator. Aside from the adjustable dials to accommodate the Japanese temporal time system, this clock also has a sophisticated calendar marking the zodiac and lunar movements. It akso has a built-in music box at the top where the 12 bells lined up horizontally will play automatically. This is the first music box to be introduced to Japan. Not only is Denjiro’s makura dokei (pillow clock) the first clock in Japan to have built-in music box, but it is an invaluable cultural heritage marking the high level of mechanical craftsmanship in Japan at the end of the Edo period.

Warigoma style shaku dokei (ruler ckock)
The warigoma style dials commonly used in dai dokei (grandfater clocks) and makura dokei (pillow clocks) is a round dial with ridges carved around the perimeter. A sliding gold piece (it is called warigoma because of its similarity to the shogi koma or chessman piece) is attached to the dial and time is read according to the season. In contrast, shaku dokei (ruler clock) has a diamond shaped gold piece or warigoma which slides along the insider slit of the dial plate. We can observe from the use of the single foliot escapment and the gold lacquer work that this warigoma style shaku dokei (rule clock) on display was made in the mid-Edo period, the early stages of shaku dokei histry.

Shaku dokei (ruler clocks) with calibration
The shaku dokei (ruler clock) is a wall-mounted clock in a rectangular case with a calibration below. One is able to read the time by looking at the moving hand along the scale. Compared to other Japanese clocks such as the yagura dokei (lantern clock) and makura dokei (pillow clock) , the shaku dokei (ruler clock) is simple in mechanism and inexpensive, thus resulting large production of this particular wadokei at the end of the Edo period. The vertical time scale of the shaku dokei (ruler clock) was very unusual among Western mechanical clocks. The shaku dokei (ruler clock), along with the double foliot escapment and the versatile dial mechanisms, ikkustrates the unique mechanical technology of wadokei in Japan. There are three types of scaled dials: the wearisome style dial where time is indicated using a sliding gold piece along the scaled dial; the setsuban style dial comprising of 7 separate dials having 13 differing scales corresponding to the Japanese temporal time system; and the haban style dial where time is graphed on a single dial according to seasons. The shaku dokei (ruler clock) on exhibit is an example of a setuban style dial.

Chahakobi Ningyo (tea carrying doll)
The mechanism of the chahakobi doll is basically the same as the wadokei of this time; the doll carries the tea cup to customer has finished drinking the tea. The chahakobi ningyo was a popular mechanical doll during this period as evident form songs written by Saikaku Ihara.

Made by Shobei Tamaya
Owari in Chubu region has been famous foro mechanical floats since the Edo period. It is said that Tmaya, sho made the chahakobi doll, moved from Kyoto to Nagoya in the middle of the Edo period to produce and repair these mechanical floats and presently Tmaya Shobei Ⅸ is in charge. THis mechanical doll uses whalefin springs, truely reproducing the chahakobi doll of the Edo period.

Made by the Mechanical Engineering Department, Tokyo Metropolitan University
This is a chahokobi doll donated by the Mechanical Engineering Department of the Tokyo Metropolitan University in 1977. It is a reproduction according to the illustration of the Chahakobi Ningyo in the book titled Krakurizui (by Hanzo Hosokawa, 3 volumes) published in 1796.

Taihei’s world technique
Due to isolation, and unlike the contemporary Western world, peace continued for 260 years during the Edo period. Original technology was developed in response to the needs of daily life. Technologies like firearms and air guns became impractical, and energy was diverted to making flint automatically and generating light. Everyone – from common people to samurai – enjoyed these technological innovations.

Erekiteru (a power generator)
Gennai Hiraga developed this friction power generator around 1776. (This unit is a replica. The original is in the collection of Japan’s Telecommunications Museum. It has been designated an important cultural property.) Erekiteru was the first electrical machine to be made in Japan. The process of rubbing a glass cylinder against a gilded pad generates static electricity. Electricity was thought to improve the constitution of the human body by taking excess “fire” from the body and adjusting its balance. But this phenomenon gained popularity solely as a spectacle. In 1770, when Gennai Hiraga journeyed to the city of Nagasaki to study gor the second time, he procured a broken electrostatic generator from an interpreter of the Dutch language in the city, which at the time was Japan’s window to the Western world. He succeeded in reconstructing the generator around 1776.

Oranda Shisei Erekiteru Kyurigen (The original scientific theory of the first system of Dutch power generators)
Oranda Shisei Erekiteru Kyurigen consists of words dictated by Donsai Hashimoto in 1811. This manuscript was Japan’s first technical manuscript pertaining to electricity. This manuscript describes various experiments for two kinds of ways toproduce electricity. For instance, there is an illustration of fire being obtained from the sky in Kumatoridani in Senshu (Izumi Province). Another diagram shows the process of frightening 100 people. A followe of Donsai Hashimoto transcribed the contents of his dictated words. The publication of his words was not permitted, and only this transcribed manuscript remains.

Automatic refueling lamp
Hisashige Tnaka designed this lamp about the time of the Tenpo period (1830-1843), a time of nationwide famine and major regorms. He applied the principle of a Dutch-made “wind gun” (an air gun). Moving the lamp’s cylinder up and down pressurizes the air at the bottom, and oil is thereby supplied upward to the lamp’s wick. Tanaka made the wick from heavy Unsai cotton, a material used for such puiposes as the bottoms of tabi (Japanese socks with the big toe separated).

Traveler’s pillow and lantern
This portable pillow was used for travel in the Edo period (1600-1868). A small andon (lantern), a candle, an abacus, writing implements, and other objects can be stored compactly inside the wooden box. The small cushion that is attached was designed for use as a piollow at night.

Collapsible candlestick
Small portable lamp made of brass. By removing its fire grate and closing its legs, this candlestick can be compactly folded into a flat object that can be stowed in a pocker-sized wallet and carried around. Because of its shape it was also called a tsurukubi (crane-neck) candlestick.

Stylish beauty
People in the Edo period were interested in aesthetics and playfulness in daily life. They also incorporated original wisdom and improvements into the knowledge and technology transmitted from the Western world.

National Museum of Nature and Science, Japan
Established in 1877, the National Museum of Nature and Science boasts one of the richest histories of any museum in Japan. It is Japan’s only nationally administered comprehensive science museum, and is a central institute for research in natural history and history of science and technology.

Each floor of National Museum of Nature and Science is organized around a unifying theme, informed by the Museum’s rich and high-quality collection of original specimens. Each floor’s exhibits work together to convey a message, in turn relating to the overarching message of the permanent exhibits, “Human Beings in Coexistence with Nature.” By presenting these themes in a clear and systematic fashion, the Museum encourages visitors to think about what we can do to protect the environment in which all living things exist and to build a future of harmonious coexistence between people and the natural world.

Organized around the theme of “The Environment of the Japanese Archipelago,” the Japan Gallery offers exhibits on the nature and history of the Japanese archipelago, the process by which the modern population of Japan was formed, and the history of the relationship between the Japanese people and nature.

The theme of the Global Gallery is “The History of Life on Earth” which explores the deep interrelationships among the earth’s diverse living things, the evolution of life as environmental change drives a cycle of speciation and extinction, and the history of human ingenuity.