1857 Map North America | Atlantic Ocean of the submarine telegraph between America & Europe, with its various communications on the two continents Inset: Harbour of St. John's, Newfoundland. Includes distance chart, "Profile of the bottom of the Atlantic as sounded 1856 by the U.S. Steamer 'Arctic,'" and ill. of the "Great Atlantic cable (natural size)." "Sold by Charles Magnus." "Entered accoring to Act of Congress in 1857 by Korff Brothers."