When Washington left Philadelphia for Cambridge, he wrote to his wife as if he expected to return after a short campaign. Perhaps he said this to comfort her. Perhaps he really hoped that by a short, sharp struggle the colonies would show Great Britain that they were in earnest, and would secure the rights which had been taken from them. At any rate, from the day he took command of the army in Cambridge, Washington had one purpose in view, to attack Boston just as soon as possible. The summer was not over before he called his officers together and proposed to make the attack. They hesitated, and finally said they were not ready for so bold a move. He called a council again, the middle of October, but still he could not bring them to the point. He kept on urging it, however, as the one thing to do, and Congress at last, just at the end of the year, passed a resolution giving Washington authority to make an assault upon the British forces "in any manner he might think expedient, notwithstanding the town and property in it might be destroyed." As soon as he received this authority, Washington again called his officers together, and urged with all his might the necessity of immediate action. He thought they should make a bold attempt at once to conquer the English army in Boston. In the spring more troops would come over from England. "Strike now!" he said, "and perhaps it will not be necessary to strike again." But it was not till the middle of February that he was able to persuade his generals to agree to a move. As soon as he had won them over, he made his preparations as rapidly as possible, and on the 3d of March took possession of Dorchester Heights. That movement showed the British what was coming. If they were to stay in Boston, they would at once be attacked. They took to their ships and sailed out of Boston harbor.