If you want to know more about Kesey and that time, a good source is Tom Wolfe's The Electic Kool-Aid Acid Test that details the travels of a bus, called Further, filled with a group called the Merry Pranksters as they travelled 'round the US with Neal Cassady at the wheel. It's a funny, interesting read that solidified Wolfe's career in the school of "new journalism."