Seat of war in the environs of Philadelphia:

Scale ca. 1:656,000.
Relief shown pictorially.
Prime meridian: London.
"For the London magazine, 1777."
Available also through the Library of Congress Web site as a raster image.
LC Maps of North America, 1750-1789, 1314
Vault
AACR2: 100; 651/1; 651/2