Email Record: Maintenance of River and Harbor Works, Duluth Harbor, and Mouths of Columbia and Mississippi Rivers. Letter from Maj. J. B. Cavanaugh, Acting Chief of Engineers, U.S. Army, Transmitting Memorandum Showing the Specific Amounts Required for Maintenance of River and Harbor Works, Including Operation of Government Plant, During Fiscal Year 1910; also Memorandum Giving Certain Information in Regard to Duluth Harbor, Mouth of Columbia and Mouth of Mississippi River.