The Ancient Stereoscope

Sir vid Brcwstcr, imjuiring into the history of the stereoscopc, fiuds tliat its fundamental principio was well known to Euclid ; that it was distinctly dcscribed by Galón onc thousand five hundred ycars ago ; and that Giauibíitista Porta had, in 1509, giveu such a completo drawing of the two separate pictures as scen by e ach eyc, and of the combined picture placee between them, that we recognize in it uoi only the principio but the coustruction o the sterooscope.