It was a desperate undertaking. There were 10,000 men, and the width of the river at the point of crossing was nearly a mile. It would seem hardly possible that such a movement could, in a single night, be made without discovery by the British troops, who were lying in camp but a short distance away. The night must have been a long and anxious one for Washington, who stayed at his post of duty on the Long Island shore until the last boat of the retreating army had pushed off. The escape was a brilliant achievement and saved the American cause.