MECHANICAL ENGINEERING HERITAGE NO.30
Mechanical Calculator, ʻJIDOSOROBANʼ
This ‘JIDOSOROBAN’ is the oldest domestic mechanical calculator. It was invented by Ryoichi Yazu in 1902 and started being manufactured after being patented in a year after. The device is of a gear type, comprising one cylinder and 22 gears, and it features a unique mechanism wherein the binary system and the quinary system are employed for data entry, as is the case with an abacus. The calculator showed excellent performance, superior to foreign-made calculators at that time, including automatic shifting and automatic stopping functions.
The calculator was sold to government offices, and other entities at a price of 250 yen per unit. This first calculator manufactured in Japan is a precious machine that featured unique technologies and led the way in the use of domestic calculating machines.
Kitakyushu Literature Museum
- Hours open:
- 9:30–18:00 (Entry closes at 30 mins. before closing time.)
- Admission fee:
- Permanent exhibit: 240 yen for adults, 120 yen for junior/senior high schoolers, 60 yen for elementary school children
- Days closed:
- Monday (the following day if falling on a holiday), year-end/New Yearʼs holidays, etc.
- 4-1 Jonai, Kokurakita-ku, Kitakyushu-shi, Fukuoka 803-0813
- 15 mins. on foot from JR Kokura Sta., 10 mins. on foot from JR Nishi-Kokura Sta.