There seems to have been a lot of chaos as the British moved en mass up the road and the patriots were forced to scramble for their lives to the defenses that had been put in place on the Brooklyn Heights. The British dug in for a siege. And General Washington made the wise decision to move his troops in the middle of the night across the river to the safety of Manhattan Island. Here is wikipedia's description:
Retreat to Manhattan
Washington and the Continental Army were surrounded on Brooklyn Heights with the East River to their backs.[75]As the day went on, the British began to dig trenches, slowly coming closer to the American defenses. By doing this, the British would not have to cross over open ground to assault the American defenses as they did in Boston the year before.[76] Despite this perilous situation, Washington ordered 1,200 more men from Manhattan to Brooklyn on August 28,[75] and two Pennsylvania regiments and Colonel John Glover's regiment from Marblehead, Massachusetts responded to Washington, sending troops. Thomas Mifflin, who commanded the Pennsylvania troops after arriving, volunteered to inspect the outer defenses and report back to Washington.[77] In these outer defenses, small skirmishes were still taking place. On the afternoon of August 28, rain began to fall, and Washington had his cannons bombarded the British well into the night.[78]
As the rain continued, Washington sent a letter instructing General William Heath, who was at Kings Bridge over the Harlem River between Manhattan and what is now The Bronx, to send every flat-bottomed boat and sloop without delay, in case battalions of infantry from New Jersey came to reinforce their position.[79] At 16:00, on August 29, Washington held a meeting with his generals. Mifflin advised Washington to retreat to Manhattan while Mifflin and his Pennsylvania regiments made up the rear guard, holding the line until the rest of the army had withdrawn.[79] The generals agreed unanimously with Mifflin that retreat was the best option and Washington had orders go out by the evening.[80]
The troops were told that they were to gather up all their ammunition and baggage and prepare for a night attack.[80] By 21:00, the sick and wounded began to move to the Brooklyn Ferry in preparation for evacuation. At 23:00, Glover and his Massachusetts men, who were sailors and fishermen, began to evacuate the troops.[81]
As more troops were evacuated, more were ordered to withdraw from the lines and march to the ferry landing. Wagon wheels were muffled, and men were forbidden to talk.[81] Mifflin's rear guard was tending campfires to deceive the British. At 04:00, on August 30, Mifflin was informed that it was his unit's turn to evacuate.[82] Mifflin told the man who had been sent to order him to leave, Major Alexander Scammell, that he must be mistaken, but Scammell insisted that he was not and Mifflin ordered his troops to move out. When Mifflin's troops were within a half mile of the ferry landing, Washington rode up and demanded to know why they were not at their defenses. Edward Hand, who was leading the troops, tried to explain what had happened, but Mifflin arrived shortly.[83]Washington exclaimed "Good God. General Mifflin, I am afraid you have ruined us." Mifflin explained that he had been told that it was his turn to evacuate by Scammell; Washington told him it had been a mistake. Mifflin then led his troops back to the outer defenses.[83]
Artillery, supplies, and troops were all being evacuated across the river at this time but it was not going as fast as Washington had anticipated and daybreak soon came.[83] A fog settled in and concealed the evacuation from the British. British patrols noticed that there did not seem to be any American pickets and thus began to search the area. While they were doing this, Washington, the last man left, stepped onto the last boat.[76] At 07:00, the last American troops landed in Manhattan.[84] All 9,000 troops had been evacuated with no loss of life.[84]
