13. Washington deceived the British into believing he remained in his lines all night
During the council of war held by Washington, American artillery continued to fire into the British lines. Washington told Chief of Artillery Henry Knox to detach two guns to remain in the fortifications, firing through the night, while the rest of his guns had their axles muffled with rags. Before midnight the guns were on the disused road to Princeton. One by one American unit pulled out of their positions, formed up, and headed along the road. Wagons and baggage trains followed, bound for Burlington. By two in the morning, the entire Army was on the road. Washington left behind five hundred men, to keep the two guns firing while the army disengaged, to keep the fires burning and to generate the normal noises of a military encampment. Throughout the night, the men did their duty, before they too pulled up stakes and headed off.
In many ways, Washington’s Princeton movement was even more audacious than his attack on Trenton a week earlier. He was taking his entire army deeper into enemy-controlled territory, with little possibility of retreat to safety in Pennsylvania. The British in New York and New Jersey outnumbered him by a large factor. New Jersey was also a deeply divided state, with about equal numbers of supporters of the Patriots and the Loyalists. Washington saw an opportunity for another victory, one which would also expose New Brunswick to threats from the Continentals. New Brunswick held the pay chests for the British troops in New Jersey, another bit of information Washington gleaned from his extensive spy networks. When Cornwallis dispatched light infantry to probe the American fortifications on the morning of January 3, they found the “old fox” of which Cornwallis had casually boasted was gone.