Spectral charts. 19th-century charts of prismatic spectra for various media. These experiments were carried out by British mathematician Baden Powell

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Spectral charts. 19th-century charts of prismatic spectra for various media. These experiments were carried out by British mathematician Baden Powell (1796-1860). Down left is the angle of deviation, from 15 to 34 degrees. The materials are: caissia oil, carbon disulphide, aragonite, calcite, flint glass, topaz, rock salt, creosote, anise oil, crown glass, quartz, sassafras oil, turpentine, sulphuric acid, nitric acid, hydrochloric acid, soda, potassium, pyroligneous acid, alcohol, and water. These charts are from a collection of Powell's works on optics: 'A general and elementary view of the undulatory theory, as applied to the dispersion of light' (1841).

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Size: 2717px × 7419px
Photo credit: © KING'S COLLEGE LONDON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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