- Geological Survey (U.S.)
- Digital Commonwealth
- Boston Public Library
- U.S. Geological Survey
Relief shown by contours, isolines and spot heights. Surveyed in 1890. Henry Gannett, chief topographer; R.U. Goode, geographer in charge; triangulation by U.S. Coast and Geodetic Survey; topography compiled by H.L. Baldwin Jr. from U.S. Coast and Geodetic Survey, and U.S. Public Land Surveys.
- No known copyright restrictions. No known restrictions on use.