To shew the Probability of a Passage, have traced the Opinions relating to it from the Time such Opinions were first received; and also determined where it was always supposed to be or in what Part such Passage was: Have considered the various Evidence that there is relating to such Passage; and proposed what appears to be the properest Method at present for prosecuting the Discovery.
There are three Maps, all of which appeared necessary for the better understanding this Account. The one contains Part of _Asia_ and the _Russian_ Discoveries on the Coast of _America_; the Expedition of _de Fonte_, and clears up that seeming Inconsistency of the _Tartarian_ and _Southern Ocean_ being contiguous in that Part of _America_, from the Authority of the _Japanese_ Map of _Kempfer_, which must be of some Repute, as it is so agreeable to the _Russian_ Discoveries: If true in that Part, there is no Reason to suppose but it is in like Manner true as to the other Part which is introduced into this Map. This Map exhibits the Streight that _de Fuca_ went up, the Communication which there may be supposed agreeable to the Lights which the Accounts afford us between the Sea at the Back of _Hudson_'s Bay with that Bay, or with the _North Sea_ by _Hudson_'s Streights, or through _Cumberland_ Isles. There is also added a second Map, to shew what Expectations may be had of a Passage from _Hudson_'s Bay, according to the Discoveries made in the Year 1747. The third Map is an exact Copy from that published in the _Monarquia Indiana de Torquemada_, in which the Sea Coast of _America_ is exhibited in a different Manner from what it usually was in the Maps of that Time, compleated by the Cosmographers of _Philip_ the Third. The Work itself is in few Hands, and the Map, as far as appears, hath been only published in that Book, is now again published, as it illustrates this Work, and may be otherwise agreeable to the Curious; having a Desire not to omit any Thing which would render the Work compleat, or that would be acceptable to the Publick.
I have used uncommon Pains to be informed as to what could be any way serviceable to render this Work more compleat; and must make this publick Acknowledgement, as to the Gentlemen of the _British Museum_, who, with great Politeness and Affability, gave me all the Assistances in their Power to find if the Copy from which the Translation was made was in their Possession, which after an accurate Search for some Weeks it did not appear to be, and also their Assistance as to any other Matters which I Supposed would be of Service. I cannot pass by Mr. _Jefferys_'s Care and Exactness in executing the Maps, whose Care and Fidelity to the Publick not to impose any Thing that is spurious, but what he hath an apparent and real Authority for, is perhaps not sufficiently known.