1 piece.
Fischer, Joshua. Engraved Map.
"A Chart of Delaware Bay and River." London: ptd by Laurie & Whittle, May 12, 1794. 20 x 28 3/4 in; 508 x 730 mm. Exceptionally clean. Light vertical center fold crease, not examined out of archival frame, mat covering margins. From Laurie & Whittle's North American Pilot, 1795.
At the time of the Revolution, Fischer's Chart (first published in 1756) was the primary source for navigation to Philadelphia.
Phillips, American Maps p263.