In 1882, a Swiss physicist Daviel Colladen attempted to calculate the speed of sound in the known depths of Lake Geneva. Based upon the physics of sound transmission articulated by English physicist Lord Rayleigh, (1842–1914) and the piezoelectric effect discovered by French scientist Pierre Curie (1509–1906), in 1915, French physicist Paul Langevin (1872–1946) invented the first system designed to utilize sound waves and acoustical echoes in an underwater detection device.
In the wake of the Titanic disaster, Langevin and his colleague Constantin Chilowsky, a Russian engineer then living in Switzerland, developed what they termed a "hydrophone" as a mechanism for ships to more readily detect icebergs (the vast majority of any iceberg remains below the ocean surface). Similar systems were put to immediate use as an aid to underwater navigation by submarines.
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