The freezing over of the Potomac River and Little Hunting Creek enabled GW to survey their shorelines on this day more easily than he usually could, “the ice permitting him to work from the water at will, which greatly simplified the calculating” (Fitzpatrick, Diaries description begins John C. Fitzpatrick, ed. The Diaries of George Washington, 1748–1799. 4 vols. Boston and New York, 1925. description ends , 1:247 n.1).