John Crossley Swallow FRS (11 October 1923 – 3 December 1994) was an English

oceanographer Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamic ...

, pages 33 etter Oand 568 etter S who invented the Swallow float (sometimes referred to as a

neutral buoyancy Neutral buoyancy occurs when an object's average density is equal to the density of the fluid in which it is immersed, resulting in the buoyant force balancing the force of gravity that would otherwise cause the object to sink (if the body's densi ...

float), a scientific drifting bottle based on the messages in bottles that

shipwreck A shipwreck is the wreckage of a ship that is located either beached on land or sunken to the bottom of a body of water. Shipwrecking may be intentional or unintentional. Angela Croome reported in January 1999 that there were approximately ...

sailor A sailor, seaman, mariner, or seafarer is a person who works aboard a watercraft as part of its crew, and may work in any one of a number of different fields that are related to the operation and maintenance of a ship. The profession of the s ...

s hoped would reach inhabited shores, summoning assistance. He was elected a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...

in 1968. He candidature citation read: "''Dr. J.C. Swallow is internationally known both for his distinguished geophysical work on the voyages of H.M.S. "Challenger", and for his measurements of deep ocean currents. He is the inventor of the "Swallow float", a hydrostatically stable, freely drifting source of sound underwater, which can be followed by a ship at the surface. By numerous observations with this ingenious device, he and others have completely changed our picture of the deep circulation of the ocean, showing the presence of strong deep currents in the western North Atlantic, and a reverse flow beneath the Gulf Stream. He has recently contributed to our knowledge of the equatorial undercurrent and of other currents in the Indian Ocean. Dr. Swallow combines a devotion to his work and a careful attention to detail with a mastery of the practical handling of a research ship at sea. The quality and originality of his contributions has already been recognized in the U.S.A. by the award of the Bigelow Medal and of the Albatross Award of the American Miscellaneous Society.''"

Swallow's invention

Swallow designed his float to reach neutral buoyancy at a desired mid-water depth. The float emitted noises that could be tracked from a ship, allowing observation of the current velocity at the depth of the float. This ability to measure subsurface currents contributed to knowledge of the circulation patterns of the ocean.

Honors and awards

*1962 Henry Bryant Bigelow Medal of the

Woods Hole Oceanographic Institution The Woods Hole Oceanographic Institution (WHOI, acronym pronounced ) is a private, nonprofit research and higher education facility dedicated to the study of marine science and engineering. Established in 1930 in Woods Hole, Massachusetts, i ...

* 1994 Henry Stommel Medal of the

References

{{DEFAULTSORT:Swallow, John 1923 births 1994 deaths English oceanographers Fellows of the Royal Society Sverdrup Gold Medal Award Recipients 20th-century British inventors

Swallow's invention

Honors and awards

See also

References