Elekitel (1/2)Gennai Hiraga restores the static electricity generator "Erekiteru"

Hiraga Gennai is a multi-talented creator from the Edo period! He is famous for repairing and restoring the "Elekiteru," a device that uses friction to generate static electricity, but he also invented a fireproof cloth, held an exhibition as a botanist, wrote Joruri puppet theatre, and was Japan's first Western painter. In this article, we will focus on Hiraga Gennai and his Elekiteru.

Hiraga Gennai and his times

Hiraga Gennai was born in 1728 in Shidoura, Sanuki Province (present-day Shido, Sanuki City, Kagawa Prefecture) as the son of a low-ranking samurai who worked as a rice storehouse attendant for the Takamatsu Domain. He was known as a child prodigy from an early age, and at the age of 11 he created a mechanical hanging scroll called "Omiki Tenjin," in which the face of the Tengu on the scroll would turn red if sacred sake was offered to him. In fact, the face of the Tengu is made transparent, and when a string is pulled, flesh-colored and red paper slides out. The red paper makes Tenjin's face turn red, as if he has drunk sake, and this is why Gennai came to be known as "Tengu Kozo."

Because his father was enthusiastic about education, Gennai began studying botany (Chinese pharmacology, which also has aspects of natural history) under a domain physician from the age of 13, and Confucianism under a Confucian scholar who served the domain. When his father died at the age of 21, he inherited the family headship and began serving as a treasurer of the domain. In 1752 (the second year of the Horeki era), with the domain's permission, he went to study in Nagasaki.

You may wonder how a low-ranking samurai could study in Nagasaki, but Matsudaira Yoriyasu, the fifth lord of the Takamatsu domain at the time, was a wise ruler known as the founder of the Takamatsu domain's revival and a man who worked hard to promote industry and commerce. He also had a strong interest in botany, which is said to have made Gennai's study abroad possible.

This was also during the time of the ninth shogun, Tokugawa Ieshige. Dutch studies had been encouraged since the time of the eighth shogun, Tokugawa Yoshimune, and it seems that Tanuma Okitsugu, who held real power even after Ieshige took over the government, continued to promote Dutch studies from the perspective of mercantilist policies, which played a major role. Okitsugu later had a relationship with Gennai and became something of a patron, and it seems that he also supported Gennai's second study abroad in Nagasaki.

Returning from his studies, Gennai resigned from his feudal domain post in 1754 and had his sister's adopted husband succeed the Hiraga family. He then became an apprentice to botanist Tamura Ransui in Edo and organized Japan's first pharmaceutical and product exhibition, the Toto Pharmaceutical Association. It was similar to a modern-day exposition and the first one was held in Yushima (Bunkyo Ward, Tokyo) in 1757. Tamura Ransui acted as the organizer of the event, but it was Gennai who actually ran it. Pharmaceutical associations were held many times after that, and it was at these events that Gennai met Sugita Genpaku and Nakagawa Junan, Dutch scholars who would later publish Kaitai Shinsho.

Gennai later became an officer in the Takamatsu domain again, but eventually resigned and retired. At this time, the Takamatsu domain imposed a condition on him that he "must not serve in another domain." Thus, Gennai, freed from the ties of the domain, went on to have a wide range of success in various fields.

What is "Elekiteru"?

Gennai Hiraga's signature word is "Elekiteru." It originally referred to a device that generated static electricity using friction, a so-called friction generator, which was introduced from the Netherlands. The word originates from the Dutch word "electriciteit."

There is a misleading statement that Gennai "invented" the Elekiteru, but in fact he was the one who "repaired and restored" the Elekiteru, which had been brought over from the Netherlands.

The friction generator was invented in 1663 by German scientist Otto von Guericke. Guericke discovered that rubbing amber hard generates electricity, so he researched ways to generate electricity mechanically, and created a device that generates electricity through friction by attaching an axis to a sulfur ball instead of amber and rotating it. The friction generator was used as a medical device to cure paralysis and as a spectacle, and spread throughout the West.

It was brought to Japan in 1751 or 1763 and presented to the shogunate. In 1765, Toshiharu Goto, a botanist from the same school as Gennai, introduced it as "erekiteri" in his book "Orandabanashi." Incidentally, "Orandabanashi" is known as the first document on electricity in Japan.

Gennai Hiraga repairs and restores the Elekitel

It is not clear how Hiraga Gennai came into possession of the Elekiteru, but it is believed that he either purchased it from an antiques dealer during his second study abroad in Nagasaki in 1770, or that he inherited one from the home of Nishi Zenzaburo, a Nagasaki interpreter. The machine he acquired was broken, so Gennai set about repairing and restoring it.

However, the only reference he had was an ambiguous diagram in the Komodan, so Gennai relied on a Dutch interpreter to decipher the Dutch documents and search for a way to restore the building.

Finally, in 1776, the 5th year of the An'ei era, they succeeded in reproducing it in Fukagawa, Edo! The Elekiteru is box-shaped, and when you turn the handle sticking out of the box, a cylindrical glass jar inside spins, causing friction with the gold leaf and generating static electricity. This static electricity is stored in a storage jar (Leyden jar) and discharged outside through a copper wire protruding from the top. If you bring your finger close to the copper wire, you will hear a "crack!" and sparks will fly.

It is said that a total of 15 Elekitels were made, but only two remain today. Both were passed down in the Hiraga family but were later donated; one is kept at the Postal Museum in Tokyo Skytree Town in Sumida Ward, Tokyo, and the other at the Hiraga Gennai Memorial Museum in Sanuki City, Kagawa Prefecture.

The one at the Postal Museum is designated as an Important Cultural Property of Japan, and features a beautiful exterior decorated with Western-style arabesque patterns. In fact, the two existing Elekitels have different internal structures; the one at the Postal Museum uses a belt to turn a rotating bottle, while the one at the Hiraga Gennai Memorial Museum has gears and no storage bottle. It seems that Gennai came up with various structures and made improvements to it.

Making Elekiteru a spectacle

What did Hiraga Gennai do with the Elekitel after it had been repaired and restored? He used it mainly for spectacles. The electric sparks and shock to the hands were an unprecedented experience, and the Elekitel caused a huge boom. Even Tanuma Okitsugu is said to have seen it with his concubine. Gennai was unable to serve any feudal domain and did not have a stable income, but he was able to earn money for his living and research expenses through this spectacle.

However, since this Elekiteru was a primitive device, it was difficult to generate static electricity. As you may know, static electricity is less likely to occur in humid conditions and more likely to occur on dry winter days, but it seems that people sometimes had to keep turning the handle on bad weather days.

Moreover, people gradually grew tired of the Elekiteru as they thought that being amazed once was enough and there was no need to use it again and again. Gennai also tried to use it for electrical therapy, but it never caught on.

Elekitel lawsuit breaks out!?

Hiraga Gennai popularized the Elekitel, but in fact in 1778, a lawsuit arose over the issue of counterfeits. Gennai, who continued his research into the Elekitel, enlisted the help of Yaichi, a craftsman who lived in the same tenement house, when making one. However, Yaichi was secretly making counterfeit Elekitels and selling them for a high price. The amount was a whopping 6 ryo!