Alexander Behm (11 November 1880 in Sternberg (Mecklenburg) – 22 January 1952 in Tarp (Schleswig-Flensburg)) was a German physicist who developed working ocean echo sounder in Germany at the same time Reginald Fessenden was doing so in North America.As head of a research laboratory in Vienna (Austria) he conducted experiments concerning the propagation of sound. He tried to develop an iceberg detection system using reflected sound waves after the Titanic disaster on 15 April 1912. In the end reflected sound waves proved not to be suitable for the detection of icebergs but for measuring the depth of the sea, because the bottom of the sea reflected them well. Thus, echo sounding was born. Wikipedia
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