The post-War period saw a dramatic increase in university enrollments across the United States, thanks first to the G.I. Bill and then to the baby boom. Like other institutions, Bucknell's campus grew to accommodate a growing student body, and the university broke ground on many of the academic buildings that comprise upper campus. Chief among these is the Ellen Clarke Bertrand Library, commissioned in 1946 under Bucknell President and former Governor of Maine Horace Hildreth and opened in 1951. Other major additions from the building spree of the 1950s and 60s include the Olin Science Building and Coleman, Marts, and Swartz Halls. The 1970s brought construction of the Elaine Langone Center, the Gerhard Fieldhouse, and the Computer Center, while in the 1980s, the capacity of the Bertrand Library was doubled, facilities for engineering were substantially renovated, and the Weis Center for the Performing Arts was inaugurated.