New theory offered for collapse of Hiroshima Castle tower in the bombing

by Junji Akechi, Staff Writer

The tower of Hiroshima Castle, believed to have been blown down by the blast of the atomic bomb, is now thought to have likely collapsed under its own weight due to the destruction of the pillars below. This is what curators of the castle now presume based on eyewitness testimonies and photos taken in the aftermath of the bombing. An exhibition with materials related to their findings opens in the rebuilt castle tower on July 16.

Miwako Honda and Kazuhiro Tamaki, curators of the castle, have focused on the fact that the remains of the tower were not seen in an aerial photo taken after the bombing of the northern part of the moat located on the opposite side of the hypocenter. They also searched for people at the Chugoku District Military Headquarters, located on the castle grounds, and the the former Japanese army cadet school, situated northeast of the castle area, who witnessed the collapse. In addition, Ms. Honda and Mr. Tamaki reviewed other photos taken in the aftermath of the bombing and related materials.

As a result, they obtained testimony indicating that the five-tiered tower had collapsed with the three top tiers and their features remaining intact and found evidence in another photo taken after the blast in which rubble remained where the tower had been located.

Based on these findings, the two curators have concluded the following: The blast of the atomic bomb hit the lower sections of the castle tower from the south and destroyed the pillars there. The top three tiers of the tower then slid, retaining their appearance, onto the terraced walls to the northeast. The tower then soon collapsed, because the remaining pillars could not hold the tower's weight.

Ms. Honda and Mr. Tamaki remarked, "Apparently it was believed, without scientific evidence, that the tower was blown off because of the blast. We hope this matter will begin to be discussed by experts in physics and architecture."

The exhibition runs until September 5. Admission is 360 yen for adults and 180 yen for high school students and under.

(Originally published on July 14, 2010)