In the history of magic, Jean Eugène Robert-Houdin (1805-1871) is considered the father of contemporary conjuring. (Indeed, Ehrich Weiss was so influenced by the master magician that he took the stage name of Houdini in his honor.) A lifelong maker, Robert-Houdin is credited in the late 1860s with inventing an optical device called an "iridoscope" to see details within the eye. In a description of the device from the time reprinted in the journal Archives of Ophthalmology, Houdin said that "its principle is something like that upon which a water carafe is held up to the light to detect whether the contents are pure." Above is an 1866 watercolor Robert-Houdin used the device to paint of the cataracts in his own eye. It was shown as part of a recent Robert-Houdin exhibit titled "Fascination optique" at the Maison de la Magie Robert-Houdin in Blois France. (via Cabinet)
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