<論説>井戸考

Abstract

人の生活に欠くことができないものの一つに水がある。特に定住生活を営み、都市を形成するようになると、水の重要性が増し、井戸を掘削して地下水を利用することが盛んになる。本稿ではこの井戸の型式と年代を検討した結果、日本の井戸の定着は稲作を基盤とする弥生社会の確立と密接な関係があり、以後の変化を(Ⅰ)木組井戸を用いるが素掘り井戸が主体をなす弥生～古墳時代、(Ⅱ)木組井戸が主体をなす古代、(Ⅲ)石組井戸が主体をなす中世、(Ⅳ)石組井戸に加えて土製品井戸が普及する近世・近代の四期に大別できることを明らかにした。また新しい型式の普及の過程と、普及にあたって主導的な役割を果たした地域とに着目し、各期の中にも画期を設定した。そして木組井戸が最も発達する古代前期の様相は木組井戸の普及が本格化する弥生後期以後の帰結、石組井戸が卓越する中世後期の様相は木組井戸の衰退がはじまる古代後期以後の帰結、コンクリート製の井戸が主となる近代の様相は土製品組井戸が普及していく近世以後の帰結と考えた。また弥生後期以後の動きについては畿内南部、古代後期以後の動きについては畿内北部、近世以後の動きについては、ふたたび畿内南部が重要な役割を果たしたと考えうるのである。

Water is indispensable for human life. Especially when they settle down and make cities, the problem of obtaining water becomes more and more important. So it often happens that they make wells. In this article, I classified the types of the well and assessed their dates. Consequently, I can clarify that the well became populer since the Yayoi 弥生 period, as a rice cropping one, and that four periods are discernible as follows. 1) From the Yayoi period to the Kohun 古墳 period; the merely digged well without armature was dominant though the wooden well was used. 2) Ancient Ages (Nara 奈良, Heian 平安); the wooden well was dominant. 3) Middle Ages (Kamakura 鎌倉, Muromachi 室町). the stone well. 4) Modern Ages (Edo 江戸, Meiji 明治); the bricks well in addition to the stone well. Moreover, considering the diffusion process of new types and the main diffusion areas, we can suppose other durations. As to the diffusion process: 1) The diffusion of the wooden well from the late Yayoi perod led to the dominance of the wooden well in the early Ancient Ages. 2) The decline of the wooden well from the late Ancient Ages led to the dominance of the stone well in the late Middle Ages. 3) The spread of the bricks well from the early Modern Ages led to the dominance of the concrete well in the late Modern Ages. As to the main areas: 1) From the late Yayoi period to the early Ancient Ages; the south of Kinai 畿内 played an important part. 2) From the late Ancient Ages to Middle Ages; the north of Kinai. 3) Since Modern Ages; the south of Kinai again.