“Acid Test” signboard, about 1964

“The adventures of the Merry Pranksters—a band of artists, writers, and students who embraced free expression, defined a lifestyle opposed to mainstream American values, and traveled the country in a psychedelic schoolbus—were popularized in Tom Wolfe’s 1968 book The Electric Kool-Aid Acid Test. Led by the novelist Ken Kesey, the group became a symbol for the counterculture based in San Francisco during the 1960s. In the early 1990s Smithsonian curators contacted Kesey hoping to acquire the famous bus, named Furthur, but it was badly deteriorated. In 1992 they collected archival material and this colorful plywood panel, which the Pranksters used to advertise concerts and poetry readings. Fittingly, Kesey signed the deed of gift with a Day-Glo marker.”

Source: Smithsonian Legacies, ‘Mirror of America’ -http://bit.ly/12k1w4x