KOBE (Kyodo) The city of Ono, Hyogo Prefecture, plans to donate secondhand abacuses to Tonga this spring to help teach arithmetic in the South Pacific island country.

The city, traditionally known as a major producer of "soroban," is scheduled to send some 1,000 abacuses in February or March. They were collected from across the country and have been cleaned up and fixed.

Some 10 countries, including Brazil and Singapore, use the abacus, considered a useful device to visualize numbers and the calculation process, to teach arithmetic, according to the nonprofit organization International Soroban Diffusion Foundation.

In Tonga, abacuses have been used in elementary schools since 2009.

Annual production in Ono has dropped to 150,000 abacuses due mostly to the prevalence of calculators and personal computers, from around 3.6 million a year during its heyday between 1955 and 1964.

Only 15 craftsmen of the traditional calculation tool remain in the city.

The city is looking to create demand for abacuses overseas.

"It would be wonderful if children who study with the donated soroban would place orders for abacuses produced in Ono later when they reach adulthood," said Takeshi Ueda, a 32-year-old city official.

The city began collecting used abacuses in September and a total of 1,320 have been gathered from Tokyo and Hyogo, Nagano and Okayama prefectures, although only about 500 had been expected by the city.