The Adonijah S. Welch Hall collection spans from 1895 to 2010, with the bulk of the collection dating from 1985-2010. The collection is arranged in two series, Building Specifications and Drawing and Building Rehabilitation. The Building Specifications and Drawings series includes building specification, illustrations, blueprints, floor and elevation plans and drawings. The Building Rehabilitation series includes building facts and information, proposals, reports, corespondence, minutes and agendas and news clippings related to the rehabilitation of Welch Hall.