Soroban
The soroban ( Japanese 算盤 'abacus', 十 露 盤 or 珠 盤 'pearl board' ) is the Japanese abacus that is usually served with one hand while lying on the table. It consists of a frame and several rods on which there are balls. Large sorobans contain over 20 of these rods. It is more flexible, but also more demanding in its operation than the school abacus common in Europe, as it is divided into an upper (also called sky) and a lower part by a rail. In the upper part there is one ball, each with the value 5, in the lower part four or five, each with the value 1. The Soroban goes back to the Chinese Suànpán , the upper part of which however contains two spheres each, to facilitate calculations with hexadecimal units (which were unusual in Japan).
While the Suànpán was part of everyday life in China as early as the 14th century, the Soroban did not spread in Japan until the 16th century. Arithmetic artists like Mōri Shigeyoshi and arithmetic book authors like Yoshida Mitsuyoshi made him popular at the beginning of the Edo period . The Soroban remained an indispensable arithmetic aid for school and work until the 19th century. Only the school reforms at the beginning of the Meiji period , which forced Western computing techniques, were able to displace it for a short time. Since the 1920s, however, it has experienced a renaissance in the simplified form with 4 + 1 balls. With the help of the Soroban, skilful computers achieved a higher computing speed than the users of mechanical calculating machines. It only lost its importance again with affordable electronic pocket calculators , but it is still widespread in Japan today.
Similar to martial arts domiciled in Japan, there is also a ranking system for the use of the Soroban that extends up to 10th Dan .
reception
- Abacus and Sword (2010): The story of the Inoyama family is told, whose male members worked at court as accountants at the beginning of the Meiji era and were masters of Soroban.
literature
- Elmar Bohlen: Soroban. Calculate with the Japanese abacus . MEC Service, Überlingen 2011, ISBN 978-3-00-034337-7 ( website for the book ).
- Takashi Kojima: The Japanese Abacus. Its use and theory . 25th edition. Charles E. Tuttle, Rutland, Vermont 1970 ( full online version on the Internet Archive ).
- Yoshida Mitsuyoshi : Jinkōki . Wasan Institute, Tokyo 2000, pp. 28–40 (English edition with facsimile of the Japanese original).
- David Eugene Smith , Yoshio Mikami : A History of Japanese Mathematics . Open Court Publishing, Chicago 1914 ( full online version at Internet Archive ).
Web links
- Pictures of Sorobans from the computational collection of the University of Greifswald
- Images of various forms of Soroban