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Show iarr- Vlbratlons of the Sea. "Marino seiches,1' or "vibrations of the sea," are pulsations usually having periods of 15 to 20 minutes, though yurylng In different localities, and they occur on toasts In addition to the waves of short durntlon due to wind and those caused by the regular ebb and flow of tho tide. They have brought out various theories. A recent study has been made by Prof. Giovanni Gio-vanni Platanla 'at Catania, Sicily, and he concludes that the principal cause Is air waves or variations of atmospheric atmos-pheric pressure. |