As early as 1639 they had reached the Pacific under Kupilof.

A force was sent out from Yakutz, on the Lena, in 1643, which reached the Amur, and thus Russians came for the first time in contact with the Chinese, and a new method of reaching Cathay was thus obtained, while geography gained the knowledge of the extent of Northern Asia.

For, about the same time (in 1648), the Arctic Ocean was reached on the north shores of Siberia, and a fleet under the Cossack Dishinef sailed from Kolyma and reached as far as the straits known by the name of Behring.

It was not, however, till fifty years afterwards, in 1696, that the Russians reached Kamtschatka.
Notwithstanding the access of knowledge which had been gained by these successive bold pushes towards north and east, it still remained uncertain whether Siberia did not join on to the northern part of the New World discovered by Columbus and Amerigo, and in 1728 Peter the Great sent out an expedition under VITUS BEHRING, a Dane in the Russian service, with the express aim of ascertaining this point.
He reached Kamtschatka, and there built two vessels as directed by the Czar, and started on his voyage northward, coasting along the land.

When he reached a little beyond 67 deg.