Early next morning, the British out-posts perceived the rear guard crossing the East river, out of reach of their fire.
From the commencement of the action on the morning of the twenty-seventh, until the American troops had crossed the East river on the morning of the twenty-ninth, the exertions and fatigues of the Commander-in-chief were incessant.

Throughout that time, he never closed his eyes, and was almost constantly on horseback.
The manner in which this critical operation was executed, and the circumstances under which it was performed, added greatly to the reputation of the American general, in the opinion of all military men.

To withdraw, without loss, a defeated, dispirited, and undisciplined army from the view of an experienced and able officer, and to transport them in safety across a large river, while watched by a numerous and vigilant fleet, require talents of no ordinary kind; and the retreat from Long Island may justly be ranked among those skilful manoeuvres which distinguish a master in the art of war.
The attempt to defend Long Island was so perilous in itself, and so disastrous in its issue, that it was condemned by many at the time, and is yet represented as a great error of the Commander-in-chief.
But, in deciding on the wisdom of measures, the event will not always lead to a correct judgment.

Before a just opinion can be formed, it is necessary to consider the previous state of things--to weigh the motives which induced the decision--and to compare the value of the object, and the probability of securing it, with the hazards attending the attempt.
It was very desirable to preserve New York, if practicable; or, if that could not be done, to consume the campaign in the struggle for that place.

The abandonment of Long Island, besides giving the enemy secure and immediate possession of an extensive and fertile country, would certainly facilitate the success of his attempt upon New York.
It was therefore to be avoided, if possible.
The impossibility of avoiding it was not evident until the battle was fought.