Nautical chart called "blueback." Relief shown by hachures. Depths shown by soundings and isolines. Oriented with north to the left. "Entered according to Act of Congress in the year 1846, by E. & G.W. Blunt, in the Clerks office of the District Court, of the Southern District of New York." "Every authentic survey, American, English, & Spanish, has been used in the construction of this chart." "Note: We are indebted to Prof. A.D. Bache Superintendent of the U.S. Coast Survey for the improvements between Cape Henlopen (including the Delaware Bay) and Montauk Point, and the offshore Soundings, where were furnished by permission of the Sec. of the Treasury. March 1847." Includes 3 insets. Insets: Absecum Shoals and the adjacent coast, from the records of the U.S. Coast Survey -- New York Harbor and entrance, from the U.S. Coast Surveys -- Plan of Havana from the Spanish surveys. Earlier editions have note: Drawn & engraved by Charles Copley.