Nouvelles decouvertes au nord de la Mer du Sud. North Pacific.DE L’ISLE 1750 map

Carte des nouvelles decouvertes au nord de la Mer du Sud, tant à l'est de la Siberie et du Kamchatka, qu'à l'ouest de la Nouvelle Franceé [Map of new discoveries to the north of the South Seas, both in the east of Siberia and Kamchatka, and at the west of New France (Canada)]

This landmark map in the history of cartography shows "new discoveries" in the North Pacific Ocean by explorers seeking among other objectives a north west passage and a north east passage, with a number of famous cartographic errors. The map shows the tracks of explorers Spandberg (who found a sea route to Japan), Tchirikow/Chirikov in the course of discovering the Aleutian Islands and Alaska, de Frondat's 1709 crossing from China to California, and the route of the Manila Galleons. Notably, the map shows a non-existent great inland sea, marked on this map as "Mer ou Baye de l’Ouest" (Sea or Bay of the West), occupying a vast part of the American/Canadian west and opening into the Pacific Ocean. It commonly appeared on maps between c1740-1790, reaching its fullest expression on this map. The opening into the Pacific, at around 48°N - the actual location of the Juan de Fuca strait - is marked on the map as the discovery of the Greek explorer Juan de Fuca in 1592. It is likely that the Sea of the West is in fact a gross misconception of the size and shape of the Strait of Georgia, the excessive size shown on the map based on de Fuca's report that he had spent 20 days sailing it and his failure to observe that the adjacent Vancouver Island was in fact an island. The map also includes an extensive interpretation of the "discoveries" made by the almost certainly fictitious Admiral Fonte along the Pacific North West Coast of North America to Alaska. A letter documenting his supposed voyage was probably invented, written and published by a London magazine editor, but the observations contained therein found strong support from proponents of a north west passage route from the Atlantic to the Pacific. The map further shows the southern coastline of a supposed landmass east of Kamchatka discovered by Joseph-Nicolas Delisle and Aleksie Chirikov during the Great Northern Expedition in 1741 - in fact the Aleutian islands. The map shows North America divided between Spain, Great Britain and France (the French possessions themselves are divided between Nouvelle France/New France to the north and Louisiane/Louisiana to the south)