The Zöllner Illusion is an optical illusion that was first described by German psychologist Johann Karl Friedrich Zöllner in 1860. It consists of a set of parallel lines that appear to be slanted when intersected by converging lines. The illusion is caused by the brain perceiving
From Wikipedia
The Zöllner illusion is an optical illusion named after its discoverer, German astrophysicist Johann Karl Friedrich Zöllner. In 1860, Zöllner sent his discovery in a letter to physicist and scholar Johann Christian Poggendorff, editor of Annalen der Physik und Chemie, who subsequently discovered the related Poggendorff illusion in Zöllner's original drawing.