Chiefly correspondence, together with diagrams of dams, locks, and ordnance works, maps, navigational and organization charts, contracts, contract bids, and documents, relating to engineering and Ackerman's role in building Corps of Engineers dams on Missouri River conservation projects, and first atomic bomb project. Locations of projects include St. Paul, Minn., Oak Ridge, Tenn., Los Alamos, N.M., and Omaha, Neb.