. . . . . . . . . . . "Report of Col. John J. Abert and Col. James Kearney, of the United States Topographical Engineers : upon an examination of the Chesapeake and Ohio Canal from Washington City to the \"Point of Rocks\""@en . . . . . . . "Report of Col. John J. Abert and Col. James Kearney, of the United States Topographical Engineers upon an examination of the Chesapeake and Ohio Canal from Washington City to the \"Point of Rocks\""@en . . .