Statistics for occurrence #1 of “Potomac river” in chapter 35, page 495 of Allan Pinkerton, The spy in the rebellion; being a true history of the spy system of the United States Army during the late rebellion, revealing many secrets of the war hitherto not made public, compiled from official reports prepared for President Lincoln , General McClellan and the Provost-Marshal-General .:
...As an additional safeguard, I sent along with them an operative by the name of William H. Scott, who was well acquainted with the various Federal commanders, and who was to see them safely across the Potomac river .
The three men departed in good spirits, and, though fully conscious of the danger before them, thoroughly resolved to successfully accomplish what they had undertaken.
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