Dot Porter, Curator, Digital Research Services at the University of Pennsylvania Library, offers a video orientation to Penn Library’s LJS 28, Portolan atlas, by Battista Agnes. This atlas was created in Venice, between 1535 and 1538, in Italian, and it includes seven double-page navigational maps marked with place names and rhumb-lines.
See the full online facsimile of this work in Penn in Hand.
The Schoenberg Institute for Manuscript Studies 
It’s quite interesting how the Azores Archipelago, with its very important ports in the Atlantic sailing, is still missing. Angra was already a Diocese since 1534.
all best,