Takuji was born on October 17, 1869, to a family of samurai in Sendai, a city in the Miyagi Prefecture.
He started the first kindergarten on the island, and took part in a venture enterprise of culturing black pearls in Kabira Bay with Mikimoto Kōkichi.
Takuji proposed that all buildings in typhoon-prone Ishigaki Island be built in concrete, including his observatory.
He also bred butterflies such as Oogomadara (Idea leuconoe) and Konoha Cho, and observed their behaviour.
He bred the poisonous Sakishima habu (Trimeresurus elegans) and devised ways to cope with the snake.
Takuji had collected a number of folklore and local songs, and tried to introduce the culture of Ishigaki Island through Yanagita Kunio and Orikuchi Shinobu.