Relief shown by hachures. Depths shown by soundings and shading. "Verified by A.A. Humphreys, Lieut. Topl. Engrs. & assistant." "Final reduction for engraving by J.B. Glück draughtsman. Topography engraved by A. Rolle, lettering by J. Knight. Electrotyped by S. Siebert, printed by H. Benner."--Lower margin. Latitude and longitude given at New London Light House. Includes tidal chart and text on sailing directions and dangers.