Relief shown pictorially.
Copied from Nouvelle carte des découvertes faites par des vaisseaux Russiens aux côtes inconnues de l'Amerique septentrionale avec les pais adiacents. [St. Petersburg, Imperial Academy of Sciences, 1758] which was the "earliest map to show the discoveries of Captains Bering and Chirkof in 1741 with the tracks of the vessels in the North Pacific." cf. Wagner, Cartography of the Northwest coast.
Bar scales given in "Sea leagues 20 to a degree" and "British statute miles 69 1/2 to a degree."
Prime meridian: Ferro. Coordinates converted by cataloger to express longitude as measured from the Greenwich meridian.
From: Müller, Gerhard Friedrich. Voyages from Asia to America ... 1761.