Photo/IllutrationMichifumi Isoda, right, and Kenzo Ogaki check out an inscription on the abacus that could be the name of the original owner. (Akihiro Tanaka)

  • Photo/Illustraion
  • Photo/Illustraion

Lessons from a deadly tsunami that struck 164 years ago and a remarkable case of returned property were deciphered from inscriptions on the back of a large abacus from the Edo Period (1603-1867).

Kenzo Ogaki, 73, who operates an abacus school in Toyonaka, Osaka Prefecture, bought the old wooden calculating tool through an online auction site for 8,000 yen ($71) around 2012.

According to Ogaki, a collector who is also vice chair of the academic association of abacus history, the design suggests it was produced in the Banshu area, now the southwestern part of Hyogo Prefecture, and its size--60 centimeters long and weighing 2.5 kilograms--indicates it was used by a business outlet.

On the back of the abacus, 159 characters, including the phrase “unprecedented earthquake,” had been etched.

Ogaki mentioned the abacus to an Asahi Shimbun reporter, who then invited Michifumi Isoda, 47, a historian and associate professor of the International Research Center for Japanese Studies, to take a look.

Isoda, an expert in disaster history who has no trouble reading old-style writing, said the etchings showed the abacus was passed down from “Sukeemon, the former head of family.”

According to Isoda’s reading, the abacus was washed out to the “Nankai” sea in a tsunami spawned by an earthquake on Dec. 24, 1854. However, it was dug up from a rice paddy in a village called “Nadamura” two years later and returned to the owner.

Isoda also said the text indicates the tsunami was about 3.9 meters high and washed away “houses and warehouses,” but that residents escaped the water by fleeing to higher ground.

The inscription of the name of the carver could be read as “Heisuke” or “Hyosuke” of “Daikokuya.” Daikokuya is often a name for a business.

The bottom of the abacus casing carried characters in ink that can be read “Dai-Hei” or “Dai-Hyo.”

Isoda speculated that “Heisuke” (“Hyosuke”) was the owner of the abacus partly because “Dai-Hei” (“Dai-Hyo”) can be short for “Daikokuya’s Heisuke” (“Daikokuya’s Hyosuke)”.

Further digging was required to determine where exactly the Daikokuya shop was located and where the abacus ended up after the tsunami.

The main lead was the name “Nadamura.”

According to a dictionary of place names, a few Nadamura existed around Japan during the Edo Period.

One Nadamura was in Tokushima Prefecture and it is now part of the coastal town of Mugi.

It was assumed that Mugi was where the abacus ended up because the text said it had drifted out to the “Nankai” sea, which is off the Kii Peninsula and Shikoku island, where Tokushima Prefecture is located.

Mugi faces the Pacific Ocean on the southeastern coast of Shikoku and is enclosed by mountains and hills.

Since the Edo Period, the area has been hit by large tsunami in 1605, 1707, 1854 and 1946, most of them following earthquakes believed to have emanated from the Nankai Trough off the Pacific coast stretching from the Tokai to Kyushu regions.

According to a journal on historical Nankai earthquakes edited by the Mugi board of education, the 1707 tsunami killed more than 110 people and washed away more than 700 houses.

In the 1854 earthquake and tsunami, 662 houses were either washed away or destroyed in Mugi. Many of the residents were apparently well-prepared because another powerful earthquake that hit off the coast of the Tokai region the previous day had also shaken the town.

However, 39 people were killed in the area as the tsunami reached about 5 meters high along a river and around 6 or 7 meters high near the river mouth.

A lumber merchant named Daikokuya was run by the Okubo family in a coastal area of Mugi. It was about 200 meters from the rice paddy where the abacus was dug up.

The Asahi Shimbun asked Kiyoshi Nakayama, 87, a distant relative of the Okubo family and a member of a local civil group to conserve documentation on the Nankai area tsunami, to look for family records.

Nakayama found that “Heisuke” or “Hyosuke,” who is believed to have etched the words on the back of the abacus, was the third-generation operator of Daikokuya. He died in 1877 at the age of 69.

“Sukeemon” was the second-generation operator.

So the abacus was owned by Heisuke, got swept out to sea in the 1854 tsunami, and returned to Nagamura but was buried in a rice paddy for two years before it was found.

Shizuko Okubo, 72, the seventh-generation descendant’s wife who currently lives in Tokyo, said the family sold off items kept in a storehouse in Mugi to a secondhand dealer about six years ago, and that the abacus was likely among those items.

Isoda also happens to have a connection with Mugi town and its tsunami.

When his mother was a child, she lived with her grandparents in the town and was affected by the tsunami in 1946.

Isoda said the inscriptions on the abacus that mentioned the size of tsunami may have been intended as a warning.

“The height of the tsunami and how people escaped death by fleeing to higher ground were valuable information for disaster preparedness that may have saved the lives of local residents,” Isoda said.

He also pointed out that the chiseled letters contain traces of red paint.

“I feel the (owner’s) joy of getting the abacus back, which was a symbol of the family business, as well as the strong determination to pass on the importance of preparing for natural disasters to future generations,” Isoda said.