Statistics for occurrence #1 of “William P. Mason” in chapter 7 of Elias Nason, McClellan's Own Story: the war for the union, the soldiers who fought it, the civilians who directed it, and his relations to them.:

... the entire period, assisted by Capt. Richard B. Irwin, aide-de-camp, and during the organization of the army by the following-named officers: Capts. Joseph Kirkland, Arthur McClellan, M. T. McMahon, William P. Mason , and William F. Biddle, aides-de-camp. My personal staff, when we embarked for the Peninsula, consisted of Col. Thomas M. Key, additional aide-de-camp; Col. E. H. Wright, additional aide-de-camp...
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William P. Mason 21 13 1 1 0 user votes

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