DanielColladon%27s_Lightfountain_or_Lightpipe,LaNature(magazine),1884

Jean-Daniel Colladon (15 December 1802,

Geneva , neighboring_municipalities= Carouge, Chêne-Bougeries, Cologny, Lancy, Grand-Saconnex, Pregny-Chambésy, Vernier, Veyrier , website = https://www.geneve.ch/ Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevra ...

– 30 June 1893) was a

Swiss Swiss may refer to: * the adjectival form of Switzerland *Swiss people Places * Swiss, Missouri * Swiss, North Carolina *Swiss, West Virginia * Swiss, Wisconsin Other uses *Swiss-system tournament, in various games and sports *Swiss Internationa ...

physicist. Colladon studied law but then worked in the laboratories of Ampère and Fourier. He received an

Académie des Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the ...

award with his friend Charles Sturm for their measurement of the

speed of sound The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At , the speed of sound in air is about , or one kilometre in or one mile in . It depends strongly on temperature as wel ...

and the breaking up of water jets. Stymied by the lack of a sight of the water jet provided to the audience, he used a tube to collect and pipe sunlight to the lecture table. The light was trapped by the

total internal reflection Total internal reflection (TIR) is the optical phenomenon in which waves arriving at the interface (boundary) from one medium to another (e.g., from water to air) are not refracted into the second ("external") medium, but completely reflecte ...

of the tube until the water jet, upon which edge the light incidented at a glancing angle, broke up and carried the light in a curved flow. Colladon reported this experiment to a wider audience in the '' Comptes rendus'', the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the ...

' journal, in 1842. His experiments formed one of the core principles of modern-day

optical fiber An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means t ...

, alongside those of: * Auguste Arthur de la Rive — who demonstrated Colladon's experiment using electric arc light *

Jacques Babinet Jacques Babinet (; 5 March 1794 – 21 October 1872) was a French physicist, mathematician, and astronomer who is best known for his contributions to optics. Biography His father was Jean Babinet and mother, Marie‐Anne Félicité Bonneau d ...

— who, separately, had created the same effect using candlelight and a glass bottle and *

John Tyndall John Tyndall FRS (; 2 August 1820 – 4 December 1893) was a prominent 19th-century Irish physicist. His scientific fame arose in the 1850s from his study of diamagnetism. Later he made discoveries in the realms of infrared radiation and the ...

— who, in 1870, demonstrated that light used internal reflection to follow a specific path using a jet of water that flowed from one container to another and a beam of light. In 1841, he conducted experiments on

Lake Geneva , image = Lake Geneva by Sentinel-2.jpg , caption = Satellite image , image_bathymetry = , caption_bathymetry = , location = Switzerland, France , coords = , lake_type = Glacial lak ...

demonstrating that sound traveled over four times as fast in water as in air. He was able to transmit sound waves from Nyon to Montreux, a distance of 50 km, and envisioned developing a novel means of transmitting information via underwater sound signals between England and France via the Channel. Colladon won the Grand Prize of the Academy of Sciences in Paris for his research on the compressibility of liquids. He also worked extensively on hydraulics, steam engines, and air compressors. He invented a type of hydraulic generator that could float on water, thereby providing a constant output of energy regardless of water level. On December 25, 1844, Geneva was first illuminated by a network of gas lights, a project Colladon had been instrumental in advocating and promoting.

References

External links

History of fibreoptics
{{DEFAULTSORT:Colladon 1802 births 1893 deaths 19th-century Swiss physicists