Potomac River

Potomac River, rising in the Alleghany Mountaine, flows 400 m. eastward between Maryland and the Virginias into Chesapeake Bay; the Shenandoah is the chief tributary. The river is navigable as far up as Cumberland, and is tidal up to Washington, which is on its banks.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Potemkin * Potosi
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Portsmouth
Portsmouth
Portugal
Poseidon
Posen
Posidonius
Positivism
Posse Comitatus
Post Restante
Potemkin
Potomac River
Potosi
Potsdam
Pott, August Friedrich
Potter, John
Potter, Paul
Potteries, The
Pot-wallopers
Pourparler
Poussin, Nicolas
Powell, Baden