Relief shown by contours, isolines and spot heights.
Surveyed in 1890.
Contour interval 5 feet.
Henry Gannett, chief topographer; R.U. Goode, geographer in charge; triangulation by U.S. Coast and Geodetic Survey; topography by A.E. Wilson, under direction of H.L. Baldwin Jr. and from surveys made by the U.S. Coast and Geodetic Survey and General Land Office.