It is worthy of note that on Bellin’s map of 1749(?) Bering island is crossed by the 56th parallel of latitude, and that along the southern edge of the Arctic ocean is a route track, marked Voyage fait par Mer en 1648 par 3 vaisseaux Russiens dont un est parvenu a la Kamtschatka.” On de l’Isle’s chart of 1752 also appears the route of 1648, but Bering island (http://www.pbs.org/edens/kamchatka/bering.html) is in latitude 54°. As to the position of Bering isle, the truth, as the Wise Man tells us is oft the case, abides between the two, as the 55th parallel intersects the land in, question. At Cape Shelagskoi, d’Anville, 1737, the Russian atlas of 1745 and the de l’Isle of 1752 agree in charting four islands northeast of the cape instead of two islands to the west. This indicates a common origin to the charts, and where else can it be ascribed than to the de l’Isle map of 1732? The Russian officer, however, gives a clue as to the date when work on the map was commenced. He says :
“At that time I visited M. De I was a witness of his geographical labours as far as they had new discoveries for their object. I acted as interpreter to M. Bering in the conversations which-he had with him ; and I can assert positively that when M. de l’Isle began that. chart the second expedition was already ordered, and Captain Bering, knowing what was stilt wanting to his discoveries, offered to continue them and his lieutenants with him, and they received promotion in consequence.”
Lauridsen says :
” On January 5, 1732, the Senate gave him leave of absence to go on Venice breaks. * * * Almost simultaneously he was promoted, in regular succession, to the position of captain-commander in the Russian fleet, the next position below that of rear-admiral.”
This indicates that the expedition was decided on at least as early as January 5, 1732; possibly earlier. Fortunately we are not left to inference, for elsewhere the Russian officer says :
“Mr. de l’Isle throws discredit on our discoveries by leaving on his chart the fictitious land of Gama, which, in order to avoid conflicting with our accounts, he places (in 1752) a little more to the west and south than he did on his chart of 17322 ”
This definitely fixes the year in which de ‘Isle presented the map to the Senate.
We learn, however, from Lauridsen that ” as early as April 17 (1732). the Empress ordered that Bering’s proposition should be executed, and charged the Senate to take the necessary steps for that purpose. * * * On May 2 it [i. e., the Senate] promulgated two ukases, in which it declared the objects of the expedition and sought to indicate the necessary m means.” It is very improbable that, in the case of so dilatory a man as de l’Isle, this chart could have been elaborated and drawn, the memoir written, a report made by the Academy to the Senate, and action be taken in the fifteen days which elapsed between the order for the chart and Bering’s instructions. It is possible that the chart was drawn at the end of 1731, and that de l’Isle, for obvious reasons, gave it the earliest possible date.