Champlain's 1632 map of New France has some truly strange place names for
lower New York, which do not appear on his other maps, or on any other maps I
know of.  Most notably he calls Long Island "Isle de l'Ascension," and the the
Hudson River "Riviere de Tretres."   I.N. Stokes in his Iconography of Manhattan
Island noted these names and remarked that they "call for explanation."  I have
looked for an explanation of the origin of these names in Conrad Heidenreich's
book on the Explorations and Mapping of Samuel de Champlain, and in several
other recent books, but so far without success.  Has anybody encountered an
explanation of the source of these names?  (I suspect that they derive from some
French exploration of the New York area between 1610 and 1630.)