Mr. Roberdeau is Isaac Roberdeau (1763–1829), oldest child of Daniel Roberdeau; Daniel’s only other son was an infant at this time. Although some sources claim Isaac was at school in England until 1787 (BUCHANAN [2] description begins Roberdeau Buchanan. Genealogy of the Roberdeau Family, Including a Biography of General Daniel Roberdeau of the Revolutionary Army, and the Continental Congress; and Signer of the Articles of Confederation. Washington, D.C., 1876. description ends , 104), he had certainly returned by the spring of 1786, for in April of that year he was one of three men put in charge of the engine for the Sun Fire Company, in Alexandria (MOORE [1] description begins Gay Montague Moore. Seaport in Virginia: George Washington’s Alexandria. 1949. Reprint. Charlottesville, Va., 1972. description ends , 50). Isaac became a well-known engineer, working with Pierre L’Enfant in laying out the city of Washington.