Statistics for occurrence #1 of “Potomac river” in article pos=46 of The Daily Dispatch: March 28, 1861., [Electronic resource]:

...bill was passed appropriating $1,000 to remove the remains of Gen.Harry Lee, now in Georgia, to Virginia. Mr. McCue reported a bill for leasing out the State Penitentiary. The bill concerning the Potomac river pilot laws was passed, and the bill incorporating the Boot and Shoe Manufacturing Company, at Chester, was also passed. The Appropriation bill was ordered to its engrossment.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Potomac River (United States) 286 0 0 0 0 user votes
Potomac River (Maryland, United States) 2 0 0 0 0 user votes
Potomac River (Maryland, United States) 2 0 0 0 0 user votes

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