Ajima Naonobu (1739–1796), also called Ajima Chokuen, was born at Edo (now Tokyo) in 1732. Ajima’s father was earning 80 pyo (pyo was an annual salary of 60 kg of rice, and 80 pyo was the same salary as a landlord of an 80-person village would earn, or koku) and a samurai warrior of Lord Shinjo (Lord Shinjo belonged to the Tozawa family) in Dewa (now Yamagata Prefecture). Ajima studied mathematics first under Irie Masataka, a mathematician of the Nakanishi-ryu school, then under Yamaji Nushizumi (also called Yamaji Shuji (1704–1772)), who was the third president of the Seki-ryu school and an astronomer at Bakufu Temmongata (Shogun’s Astronomical Observatory). Then Ajima became an accountant of Lord Shinjo, at the rank of 100 koku.
Yamaji made the Horeki (Kojutsu) Rekicalendar (Calendar Made in Horeki Era 1754), which was used from 1755 to 1797; however, this calendar was not very accurate. In order to make a new lunisolar calendar, in 1762 he started to observe the sky with Fujita...
References
Hirayama, A., & Matsuoka, M. (Eds.). (1966). Ajima Naonobu Zenshu. Tokyo: Fuji Junior College Press.
Nihon, G. (Ed.). (1954). (FUJIWARA Matsusaburo). Meiji-zen Nihon Sugaku-shi. Tokyo: Iwanami Shoten.
Hayashi Tsuruichi 林鶴一 (1937). Hayashi Tsuruichi Hakushi Wasan Kenkyu Shuroku 林鶴一博士和算研究集録 (Collected Papers on the old Japanese Mathematics) (2 vols., Vol. 2. p. 42). Tokyo: Tokyo Kaiseikan 東京開成館.
Nihon Gakushiin 日本学士院 (Japanese Academy) (Ed.) (Fujiwara Shozaburo 藤原松三郎). (1954). Meiji-zen Nihon Sugaku-shi 明治前日本数学史 (History of Pre-Meiji Japanese Mathematics) (5 vols., Vol. 4, p. 199). Tokyo: Iwanami Shoten 岩波書店.
Hirayama Akira 平山諦, & Matsuoka Motohisa 松岡元久 (Eds.). (1966). Azima Naonobu Zenshu 安島直円全集 (Collection of Azima Naonobu) (pp. 5–6). Tokyo: Fuji Tanki Daigaku Shuppanbu富士短期大学出版部 (Fuji Junior College Press).
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer Science+Business Media Dordrecht
About this entry
Cite this entry
Jochi, S. (2014). Ajima Naonobu. In: Selin, H. (eds) Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-3934-5_8421-2
Download citation
DOI: https://doi.org/10.1007/978-94-007-3934-5_8421-2
Received:
Accepted:
Published:
Publisher Name: Springer, Dordrecht
Online ISBN: 978-94-007-3934-5
eBook Packages: Springer Reference Religion and PhilosophyReference Module Humanities and Social SciencesReference Module Humanities