[includes union bulletins, memorandum and subpoenas regarding an injunction made against Local 251 separating from the United Electrical, Radio & Machine Workers of America in March 1948; constitution of Unity Lodge, Local 405 of the United Automobile, Aircraft and Agricultural Implement Workers of America, C.I.O. (composed of employees of Pratt & Whitney Division, Niles-Bement-Pond Company) accepted on September 25, 1948]