耕地整理法が施行されてから50年間の耕地整理の整備方式について, 区画, 水路, 農道, 換地に留意して論述した。明治末から大正にかけて, 上野英三郎教授と横井時敬教授との間で整備方式についての論争があった。
当時の整備方式は地主が主になり, 自作と調整した方式で, 乾田馬耕という当時の技術の実現には不十分であった。鴻巣式が基本で, 標準区画は長辺30問, 短辺10間の1反区画である。初期は農道の幅員は狭く, 荷車が直接に耕区に入れなかった。後期は幅員が1間になり, リヤカーが直接に耕区に入れるようになった。鴻巣式では, 用水路と排水路が分離しているが, 排水路が浅く, 後期には用排兼用水路が登場してきた。農地の集団化は行われなかった。

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Reevaluation of places, type, magnitude, and influences of the 800-802 A.D. eruption (Enryaku eruption) of Fuji Volcano, Japan, was made through tephrochronology and analyses of historical records. The Nishi Kofuji fissure on the northeastern slope is newly recognized as a crater of the 802 A.D. flank eruption. The Nishi Kofuji fissure ejected fallout scoria toward ENE and lava flows, which can be correlated with Takamarubi and Hinokimarubi 11 Lavas on the northeastern foot. The Tenjinyama-lgatonoyama fissure on the northwestern slope probably erupted during the Enryaku eruption and ejected fallout scoria and lava fiows. A series of historical documents and paintings (Miyashita documents), which are unauthorized, personal records and are regarded to be unreliable by many historians, includes many detailed descriptions of paleogeogra-phy around Fuji Volcano and of the Enryaku eruption. Although some of the descriptions were exaggerated and conflict with geological observations, some of them are concordant with geologic data. The Enryaku eruption probably gave serious damages to ancient traffic routes particularly on the northwestern-northeastern foot of Fuji Volcano. The Gotenba area, which is located on the eastern foot, was also damaged by thin ash-fall and probably by lahars. This caused a temporal, southward relocation of the offical trafiic route, which had passed through the Gotenba area.

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