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The started on 16 December 1707 (23rd day of the 11th month of the year Hōei 4) and ended about 1 January 1708 (9th day of the 12th month of the year Hōei 4) during the Edo period.〔(Shizuoka University page )〕 Although it brought no lava flow, the Hōei eruption released some of volcanic ash, which spread over vast areas around the volcano, even reaching Edo almost away. Cinders and ash fell like rain in Izu, Kai, Sagami, and Musashi provinces.〔Titsingh, Isaac. (1834). ( ''Annales des empereurs du japon,'' p. 416. )〕 In Edo, the volcanic ash was several centimetres thick.〔()〕 The eruption is rated a 5 on the Volcanic Explosivity Index. The eruption occurred on Mount Fuji's east–north-east flank and formed three new volcanic vents, named No. 1, No. 2, and No. 3 Hōei vents. The catastrophe developed over the course of several days; an initial earthquake and explosion of cinders and ash was followed some days later with the more forceful ejections of rocks and stones.〔Smith, Henry. (1988). ''Hokusai: One Hundred Views of Mt. Fuji.'' p. 197.〕 Mount Fuji has not erupted since. Hokusai's ''One Hundred Views of Mount Fuji'' includes an image of the small crater which developed from a secondary eruption site on the southwestern slope. This was called Mount Hōei, because the eruption occurred in the fourth year of Hōei.〔 Today the crater can be visited from Fujinomiya Trail or Gotemba Trail of Mount Fuji. ==Secondary disasters== In the year following the Hōei eruption, a secondary disaster occurred when the Sakawa flooded due to sediment build-up resulting from the ash fall. Volcanic sands fell and widely covered the cultivated fields east of Mount Fuji. To recover the fields farmers cast volcanic products out to dumping-grounds and made sand piles. The rain washed sand piles from the dumping grounds away to the rivers again and again and made some of the rivers shallower, especially into the Sakawa, into which huge volumes of ash fell, resulting in temporary dams. Heavy rainfall on 7–8 August 1708, the year following the Hōei eruption, caused an avalanche of volcanic ash and mud and broke the dams, flooding the Ashigara plain. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hōei eruption of Mount Fuji」の詳細全文を読む スポンサード リンク
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