SCIENCE PHOTO LIBRARY SCIENCE PHOTO LIBRARY
John Tyndall. Coloured portrait of the Irish physicist John Tyndall (1820-93). Tyndall was a surveyor and engineer before studying physics and becoming a professor at the Royal Institution, London, England, in 1854. He wrote on a number of subjects and studied light beams passing through various substances. In 1869 he discovered the Tyndall Effect, in which light scattering by colloidal particles in a solution makes the light beam visible from the side. He realised that the sky is blue because dust particles in the air scatter the shorter blue wavelengths of sunlight more than the longer red wavelengths. Taken from A Modern Portrait Gallery, volume 3 (1881).
Model release not available. Property release not required.