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Reprints of county topographical maps are available from the Maryland Department of Natural Resources, Maryland Geological Survey, 2300 St. Paul St., Baltimore, MD 21218. A good collection of maps, atlases, and plats is at the Maryland State Archives, many of which are indexed by place and some by names of tracts and owners. Early maps of Maryland are in Russell Morrison, and others, On the Map (Chestertown, Md.: Washington College, 1983). Other fine and useful maps are at the Maryland Historical Society. Mary Ross Brown, An Illustrated Genealogy of the Counties of Maryland and the District of Columbia (Silver Spring, Md.: the author, 1967) includes maps that show the county changes and also ward maps of Baltimore for 1850, 1860, 1870, and 1880. Atlases have been published for some of the counties, and county maps are to be found in most county histories.
For the best study of mapping in Maryland, see Edward C. Papenfuse and Joseph M. Coale, III, Atlas of Historical Maps of Maryland, 1608–1908, revised with the new title The Maryland State Archives Atlas of Historical Maps of Maryland, 1608–1908 (Baltimore: Johns Hopkins University Press, 1982, 2003).