1867 (illustration) 1869 (published) Sorensen's Engraving Pantograph in use by the U.S. Coast Survey 1867
Engraving, from a photograph, cropped Creative Commons - Wikipedia National Oceanic & Atmospheric Adminstration (NOAA), NOAA Central Library, Image ID: theb1160, NOAA's Historic Coast & Geodetic Survey (C&GS) Collection
1869, Report of the superintendent of the U.S. Coast and Geodetic Survey showing The Progress of the Work during the Fiscal Year 1867 (Washington: Government Printing Office), fig. 27
