200年以上むかしの、時速1380kmのアナログな光通信網。[1,380km per an hour analog optical communication network more than 200 years ago.]

Email in the 18th century by Low-tech Magazine.

５〜６km間隔に配置された塔による通信網。だいたい東京から鹿児島まで１時間で連絡できるイメージ。
A communications network by a tower arranged to 5~6km distance. Generally it is the feeling that it can contact from Tokyo to Kagoshima in one hour.
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