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Re: New Madrid helicorders |
Ara; No, a Helicorder (helical recorder) is a recording device for seismometers which uses a strip of black paper covered with white wax wrapped around a cylinder. A hot pen melts the wax as the drum turns, making a black line. The pen slowly moves across the drum so the line is a spiral. When the paper is removed you see a series of lines depicting the signals. Roger Follow Ups: ● Re: New Madrid helicorders - Ara 22:40:46 - 9/20/2005 (28440) (0) |
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