Gennai Hiraga: The Edo-Era Wizard Who Shocked Japan with the “Elekiter”

I’m Ken Kuwako, a Science Trainer. Every day is an experiment!

Have you ever heard the word “Elekiter”? The Elekiter was the very first full-scale “static electricity generator” to be officially introduced to Japan.

【Listen to this article on the radio here】

Quoted from “Biography of Gennai Hiraga” (Shueisha)

The man who repaired and restored this “magical” machine—a broken device imported from the Netherlands—and thus etched his name into the history of Japanese science, was none other than Gennai Hiraga. When you hear “static electricity,” you might think of that little “zap!” you get when you touch a doorknob in the winter. But did you know that even in Japan’s Edo Period, experiments using static electricity were already being conducted?

The first person to successfully restore the Elekiter (static electricity generator) in Japan was the master Gennai Hiraga.

The Elekiter’s mechanism is essentially a combination of a “Van de Graaff generator” (for producing static electricity) and a “Leyden Jar” (a device for storing the charge), both of which you might find in a modern school science lab. By turning a handle, it creates static electricity through friction (the Van de Graaff’s role) and then stores that electrical charge in a storage jar (the Leyden Jar’s role).

It is said that Gennai Hiraga used this device to perform static electricity experiments and “Electric Shows” for feudal lords and common townspeople. Imagine him making someone touch the stored electricity for a shocking “ZAP!” or shooting sparks in the dark… He must have seemed like a true wizard!

The Location of Gennai Hiraga’s Experiments

The place where Gennai Hiraga reportedly conducted his experiments is still standing today in Kiyosumi-Shirakawa, Tokyo. Doesn’t it sound exciting that a site for cutting-edge science experiments from the Edo Period remains in the modern world? I decided to visit this very spot. Let’s trace the stage of Edo-era science and delve deeper into the achievements of Gennai Hiraga!

Site of Gennai Hiraga’s Elekiter Experiments

A stone monument now stands at the site where Gennai Hiraga performed his Elekiter experiments. Here is the location:

〒135-0024 東京都江東区清澄1-2-1

I actually went there! It’s about a 10-minute walk from Kiyosumi-Shirakawa Station. I even saw it mentioned on a sign near the station.

I left Kiyosumi-Shirakawa Subway Station and started walking toward the Sumida River.

When I reached the Sumida River, I turned left without crossing the bridge.

It looked like a pretty ordinary area, but just past this building…

Monument found! So this is where it all happened. Apparently, Gennai Hiraga’s residence used to stand right here.

I paid my respects here, placing my personal Japanese static electricity device, “Gennai Hiraga,” along with a Narika product “Electrostatic High-Voltage Generator” (Zenicon) and a homemade “Leyden Jar.” These two are essentially the modern Elekiter set!

As a static electricity enthusiast myself, I had to take a photo in front of Gennai Hiraga’s monument.

I was definitely getting some suspicious looks from people passing by. But I didn’t care! Standing in this very spot and imagining Gennai Hiraga conducting his experiments (or “shows,” as they might have been), I was overwhelmed with emotion.

Quoted from “Biography of Gennai Hiraga” (Shueisha), p.120

Visiting Gennai Hiraga’s Grave!

Next, I visited Gennai Hiraga’s grave. It’s about a 15-minute walk from Minami-Senju Station—a bit of a journey, but certainly walkable.

〒111-0023 東京都台東区橋場２丁目２２−２

It’s a bit tricky to find, but the gate is on the south side, requiring you to walk around the building.

I was told that if the gate is closed, as long as it’s unlocked, you’re allowed to enter. Thankfully, it was open today!

There was a sign at the gate detailing the achievements of Gennai Hiraga.

One commemorative photo.

After passing through the gate and walking around, I found…

The grave of Gennai Hiraga. In his later years, he accidentally killed a person, became a criminal, and died in prison. It was long believed that his remains wouldn’t be there since he was a criminal, but when they were actually investigated around 1900, his bones were indeed found.

And guess what? This grave was built by his friends, including Genpaku Sugita, who is famous for the groundbreaking medical text Kaitai Shinsho. Even as a criminal, he had friends who remembered his achievements and valued their friendship. I placed my favorite magazine, Otona no Kagaku Magazine’s Elekiter issue, next to the grave for a photo.

He was my favorite scientist—or perhaps inventor—since elementary school. I took a moment to reflect on all my thoughts and feelings about him here.

From Elekiter to Modern Day: The Baton of Science

The Elekiter, restored by Gennai Hiraga, was a giant leap in the history of Japanese science. This scientific baton was passed down to Sokichi Hashimoto, often called the “Father of Japanese Electrical Studies.” You can find more details in this article.

From a National Museum of Nature and Science exhibit description

Today, the “static electricity” that Gennai Hiraga used to amaze crowds has evolved into the familiar “Van de Graaff generator,” a staple in any science class.

Check Out These Cool Experiments with a Van de Graaff Generator!

We’ve also published some fun experiments using the Van de Graaff generator. This includes experiments we performed on TV shows with celebrities like Suzu Hirose, Ryohei Suzuki, Yasuko, and Osada and Matsuo from Chocolate Planet! Click here for details.

* NOTE: Any experiments using a static electricity generator (Van de Graaff) must be performed under the supervision of an expert. Please proceed with caution! For requests regarding static electricity experiments (science classes, TV supervision/appearances, etc.), please contact us here.

【Feature】Static Electricity Experiments You Won’t Be Able to Stop Doing!

Contact & Requests

We’re here to bring the wonder and fun of science closer to you! We provide easy-to-understand summaries of fun science experiments you can do at home, along with tips and tricks. Feel free to search around! ・The content from our science blog has been published as a book. Details here. ・About the site administrator, Ken Kuwako, click here. ・For various requests (writing, lectures, science classes, TV supervision/appearances, etc.), please click here. ・Article updates are posted on X!

Experiment videos are available on the Kagaku no Neta Channel!

３月のイチオシ実験！

• 押し花を作ろう！：梅や桜の花の押し花を作ってみましょう。特別なケースに入れると、長く保存できて、しおりにもなります。

テレビ番組・科学監修等のお知らせ

• 「月曜から夜更かし」（日本テレビ）にて科学監修・出演しました。
• 2月27日放送予定「チコちゃんに叱られる」（NHK）の科学監修しました。

書籍のお知らせ

• 1/27 『見えない力と遊ぼう！電気・磁石・熱の実験』（工学社）を執筆しました。
• サクセス15 ２月号にて「浸透圧」に関する科学記事を執筆しました。
• 『大人のための高校物理復習帳』（講談社）…一般向けに日常の物理について公式を元に紐解きました。特設サイトでは実験を多数紹介しています。※増刷がかかり６刷となりました（2026/02/01）
• 『きめる!共通テスト 物理基礎 改訂版』（学研）…　高校物理の参考書です。イラストを多くしてイメージが持てるように描きました。授業についていけない、物理が苦手、そんな生徒におすすめです。特設サイトはこちら。

講師・ショー・その他お知らせ

• 3/20（金）　日本理科教育学会オンライン全国大会2026「慣性の法則の概念形成を目指した探究的な学びの実践」について発表します。B会場 第３セッション： 学習指導・教材（中学校）③　11:20-12:20
• 7/18（土）　教員向け実験講習会「ナリカカサイエンスアカデミー」の講師をします。お会いしましょう。
• 10/10（土）　秘密兵器「帯電ガン」が炸裂！ビリビリ！ドキドキ！静電気サイエンスショー＠千葉市科学フェスタ（午後予定）
• 各種SNS　X(Twitter)／instagram／Facebook／BlueSky／Threads

Explore

• 楽しい実験…お子さんと一緒に夢中になれるイチオシの科学実験を多数紹介しています。また、高校物理の理解を深めるための動画教材も用意しました。
• 理科の教材… 理科教師をバックアップ！授業の質を高め、準備を効率化するための選りすぐりの教材を紹介しています。
• Youtube…科学実験等の動画を配信しています。
• 科学ラジオ …科学トピックをほぼ毎日配信中！AI技術を駆使して作成した「耳で楽しむ科学」をお届けします。
• 講演 …全国各地で実験講習会・サイエンスショー等を行っています。
• About …「科学のネタ帳」のコンセプトや、運営者である桑子研のプロフィール・想いをまとめています。
• お問い合わせ …実験教室のご依頼、執筆・講演の相談、科学監修等はこちらのフォームからお寄せください。