Sketch B. Showing the Progress of Section No. 2, U.S. Coast Survey, 1844 to 1851
Cartographer / Artist: U.S. Coast Survey (Alexander Dallas Bache, Superintendent)
Date: 1851
Medium: Engraving on paper
Dimensions: 11.8 × 11.5 inches
Location: Delaware Bay, New Jersey, Delaware, Pennsylvania, United States
This mid-nineteenth-century progress sketch was published by the United States Coast Survey under the direction of Superintendent Alexander Dallas Bache. Designated as Section No. 2 of the federal coastal survey program, the chart documents geodesic and hydrographic survey advancements undertaken between 1844 and 1851 across the Delaware River, Delaware Bay, and southern New Jersey coastline.
The map meticulously illustrates primary and secondary triangulation stations, baseline networks, and trigonometric linkages stretching from Philadelphia and Wilmington south to Cape Henlopen and Cape May. Prominent maritime navigational hazards, including sandbars, channels, and named shoals (such as Joe Flogger Shoal, Brandywine Shoal, and Cross Ledge), are systematically charted alongside inland transport routes and regional coastal geography.