著者

米地 文夫 Fumio Yonechi ハーナムキヤ景観研究所

出版者

岩手県立大学総合政策学会

雑誌

総合政策 = Journal of policy studies (ISSN:13446347)

巻号頁・発行日

vol.13, no.2, pp.103-118, 2012-05-01

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宮沢賢治は土壌や地質の調査に地図を用い、測量も行ったので、その体験が作品に反映している。彼の代表作「銀河鉄道の夜」の天の野原に立つ無数の「三角標」の描写もその例である。この「三角標」は「測標(一時的に設けた三角測量用の木製の櫓で、当時は三角覘標と呼ばれた)」から賢治が考えた語とする解釈が一般的である。しかし1887年に参謀本部陸地測量部が刊行した文書には、地図記号の中に「三角標」の名の記号があり、現在の三角点を公的に三角標と呼んでいた時期が数年間あった。その後、公的には使われなくなったが、登山家の間では三角覘標(現在では測標と呼ばれる)を三角標と呼ぶことが多く、賢治もこの俗用の三角標の語を用い、ほかにも1911年の短歌など数作品に同様の例がある。また、銀河鉄道の沿線に立つ三角標の発想には、里程標もモデルにしたとみられる。恒星までの距離を太陽を回る軌道上の地球から、年周視差を使って半年おきに二点から恒星を観測し距離を三角測量法によって測定されていることを賢治は知っていた筈である。つまり輝く星は、地上から観測する測標(賢治の三角標)に当たり、回照器の鏡を動かし陽光にきらめかせて位置を観測者に知らせる測標に見立てたのである。「銀河鉄道の夜」のなかで列車がまず目指した白鳥座の三角標には白鳥の測量旗があると書かれているが、白鳥座61番星はこの方法で地球からの距離を測った最初の星であった。「銀河鉄道の夜」で賢治は、星座早見盤を地図に見立て、星を三角測量の測標に見立てたのであり、賢治が地図や測量に強い関心を持ち、これを発想の重要な柱としていたことが良くわかる作品なのである。Kenji Miyazawa had used maps for soil and geological research and to conduct land surveys, and these experiences were later reflected in his work. One example of this is his depiction of a myriad of sankaku-hyo (triangulation markers) placed in the field of the sky along the railroad in the novella Night on the Milky Way Railroad, one of his most prominent works. The sankaku-hyo is generally considered a term he invented based on soku-hyo, which was referred to as sankaku-tenbyo at that time and which meant a temporarily-installed wooden scaffold for triangular surveying. However, a map symbol referred to as sankaku-hyo was actually used in a document issued by the Survey Department of the General Staff Office in 1887, and the current sankaku-ten (triangulation point) was officially known as sankaku-hyo for several years. Following this, the term sankaku-hyo no longer appeared in official use, but climbers still often refer to a sankaku-tenbyo as a sankaku-hyo. Miyazawa used this popular term, sankaku-hyo, in his novella, as well as in several other works, including tanka poems he wrote in 1911. This idea of sankaku-hyo placed along the Milky Way Railroad is also considered to have been modeled after milepost. Miyazawa must have known that the distance to a fixed star is measured from two points on the Earth, as it orbits the Sun, using heliocentric parallax every six months based on the triangular surveying method. Specifically, luminous stars correspond to soku-hyo (sankaku-hyo in his work) observed from the Earth, and he likened these stars to soku-hyo that inform observers of their location when they twinkle as the mirror of the heliotrope moves. In Night on the Milky Way Railroad, Miyazawa wrote there is a swan on each of the land survey flags placed at the sankaku-hyo for the Swan. Indeed the 61st star of the Swan is the first star for which distance from the Earth was measured using this method. In Night on the Milky Way Railroad, Miyazawa likens a star plate to a map and stars to soku-hyo for triangular surveying. This work clearly suggests that the writer had a strong interest in maps and surveying and that they were the essential elements underlying his ideas.