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pl23_ship3235.jpg

Image

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https://www.noaa.gov/media/digital-library-photo/pl23ship3235jpg

Description

Images relating to acoustic signaling by means of Reginald Fessenden's electricoscillator. In Submarine Signaling, Scientific AmericanSupplement, No. 2071, pp. 168-170, Sept. 11, 1915.

Collection

Voyage to Inner Space