The Philadelphia Mass Turbulence of 1947 was an event of high psychokinetic activity. Not much is known of the event except it was one of the most impressive forms of Symmetrical Stacking to date. A similar event to it was encountered by the Drs. Peter Venkman, Ray Stantz, and Egon Spengler at the New York City Public Library in 1984, believed to have been instigated by the Library ghost.