Japanese version is here .
May 6, 1999. In Japan, numerous documents, which include descriptions about volcanic and possible volcanic activities, were found and are still being found in various historical literatures, which were written during the 6th century to the recent time. Such descriptions have been collected and interpreted since the end of the 19th century by volcanologists and several databooks were published in the early half of the 20th century. However, most of all the Japanese volcanologists did not know and still do not know how to evaluate the reliability of historical documents, which often include many mistakes, falsehoods, and inaccurate descriptions. Such a situation is not good for the development of volcanology and disaster prevention in Japan.