(Roughly) Daily

Another blow to the evidence of one’s own eyes…

Optical illusions are perceptual effects that arise from interpretations of an image by the brain.  Entopic phenomena, on the other hand, are visual effects whose source is within the eye itself… and entropic phenomena, like other illusions, have led to interesting– but incorrect– conclusions…  During the 1920s, e.g., some Theosophists, unaware of the physical explanation, maintained that some entoptic phenomenon were “vitality globules” related to the concept of prana in yoga.

William Hundley has posted a remarkable set of photos– beautiful studies of fabrics, floating– that mimic one particular variety of entropic effect: the  intra-optic illusion known as a “floater”: “deposits of various size, shape, consistency, refractive index, and motility within the eye’s vitreous humor, which is normally transparent,” and which give rise to shadow-like shapes that float before the eyes…

They are here on Flickr, and here on Hundley’s own site.

As we clean our glasses, we might carefully compose a birthday greeting to Pierre Athanase Larousse, the French grammarian and lexicographer, born in Toucy on this date in 1817.  In 1856 Larousse and his partner Augustin Boyer published the New Dictionary of the French Language, the forerunner of the Petit Larousse.   On December 27, 1863 the first volume of Larousse’s masterwork, the great encyclopedic dictionary, the Grand dictionnaire universel du XIXe siècle (Great Universal 19th-Century Dictionary), appeared.

The cover of the first Larousse French dictionary (1856)

Written by (Roughly) Daily

October 23, 2008 at 1:01 am

Posted in Uncategorized

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