Correspondence, speeches, manuscripts of technical papers, maps, plans, charts, photographs, books, pamphlets, and journals relating to marine growth, flood control (particularly to the development and installation of revetments on the Misissippi River), and other civil engineering topics and projects. Among the photographs are visual records of flood projects in progress and shots taken on a trip to the Netherlands in 1937. Many of the printed items (mostly produced by the Mississippi River Commission and the Corps of Engineers) were marked by Carey as "rare and valuable." Correspondents include General John R. Hardin, General Harley B. Ferguson, Congressman Paul H. Maloney, Dr. P.W. Zimmerman, Herbert D. Vogel, and Bernard E. Gray.