Hekla volcano, in southern Iceland, erupted on March 29, 1947, after 102 quiescent years. Of the ash and pumice ejected, some fell on a fishing trawler 39 miles south of the volcano. This material has been examined microscopically, a mechanical analysis made, and the terminal velocities of the various fragment sizes determined. The probable track of the transported ash, the weather conditions, and the factors affecting sorting are discussed.

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