Kunitomo Ikkansai (国友一貫斎)

Ikkansai KUNITOMO (November 21, 1778 - December 26, 1840), the ninth Tobei KUNITOMO, was a gun (teppo in Japanese) smith and an inventor. His childhood name was Toichi. His pseudonym name was Ikkansai, or Minryu. His real name was Shigeyasu. His inscription was Yoshitomi. He invented Japan's first air gun for actual combat and an astronomical telescope. He performed astronomical observation by the telescope he invented.

Biography
He was born to a teppo (gun) smith family patronized by the Shogunate in Kunitomo of the Province of Omi (Kunitomo, Nagahama City, Shiga Prefecture). He succeeded the "Tobei" name from his father at age 9, and at 17, he inherited the position of toshiyoriwaki.

In 1811, he became Goyo-gakari (someone formally employed for a specific task or position) for the Hikone clan, and received an order for 200 medamazutsu (a type of cannon). The four toshiyori (one rank above toshiyoriwaki) families in Kunitomo village, objected to him being favored despite his lower rank, which resulted in a long lasting conflict (Hikone Incident). However, Ikkansai's exceptional skills were recognized, and the case ended with the toshiyori's loss.

In 1819, he invented "Kiho", a powerful air gun for battle use, based on "Fuho", a toy air gun introduced from Holland. He wrote "Kihoki" as an instruction manual, and later he completed the 20 repeater kiho.

He had a chance to see a reflecting telescope during the Bunsei era, and he started to develop a Gregorian reflecting telescope from around 1832. His telescope was of far more superior quality than the other telescopes made at the time; it had a diameter of 60mm, and could magnify up to 60 times. Later, the telescopes were said to be sold to Daimyo families and the like for the victims of the Tempo Famine. In present day, they are kept at the Ueda City museum and Hikone Castle museum.

Furthermore, he is an inventor with numerous inventions such as Gyouto (lightening tools), Japanese pens with tips like a brush, steel crossbow, and Shinkyo (mirror used for fortune-telling).

With the telescope he invented in 1835, He performed a sunspot observation for what was considered a relatively long time during his period. He left sketches of the moon and Saturn among others and some claim he even left sketches of Titan (satellite). He is considered one of the pioneers of astronomy in Japan.

He died in Kunitomo village in 1840. Age at death 63.

Tobei KUNITOMO
One of the gun smith families in Kunitomo village patronized by the government that had the rank of toshiyoriwaki (a hereditary rank given to gun smith families), which was one below toshiyori. It is also called Tujimura family.

Ikkansai was the ninth family head with the name "Tobei KUNITOMO", but as he was especially famous, the name usually refers to him. The first Tonai TSUJIMURA (KUNITOMO) was a smith from Mino Province, and settled in Kunitomo village in Omi Province during Eisho era. Most of the successors after the second head of the family took the name of Tobei KUNITOMO. Other smiths in Kunitomo took the name Shigetomi. Shigetomi is the commonly-used inscription which means the bullets "consecutively hit", but only the family of Tobei uses Yoshitomi. It means "hit well".
After entering the Meiji era, under the 11th head of the family, the family withdrew from the gun making business

[Original Japanese]