LSD Acid Tests Original Card – Card described as original ephemera connected with Ken Kesey and the Merry Pranksters’ Acid Tests of 1965–1966. These experimental multimedia gatherings combined music, projected imagery, sound, performance, and LSD and became important precursors to the San Francisco psychedelic scene. The Grateful Dead performed at several Acid Tests during the group’s early development. Because reproductions and later commemorative pieces exist, printing method, paper, dimensions, aging, and provenance should be carefully evaluated.