Map showing a portion of the boundaries of Maryland, Pennsylvania, & Delaware : as surveyed in 1849 & '50, under the direction of Lieutenant Colonel J.D. Graham, U.S. Topl. Engineers, at the request of H.G.S. Key, Joshua P. Eyre, & Geo. Read
from Parts (In 3 layers) Depicts: 1850 Last modified almost 6 years ago. Unrectified.
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