Washington made his headquarters at the house of Robert Murray on the 14th. The position of the American army now appeared more perilous than ever. Two ships-of-war had passed up the East River. Others soon followed. Scouts reported active movements among the British troops everywhere, but could not penetrate, even by reasonable conjecture, the designs of the enemy. It was of the utmost importance to know something of their real intentions. Washington wrote to General Heath, then stationed at Kingsbridge: "As everything, in a manner, depends upon obtaining intelligence of the enemy's motions, I do most earnestly entreat you and General Clinton to exert yourselves to accomplish this most desirable end. Leave no stone unturned, nor do not stick at expense, to bring this to pass, as I was never more uneasy than on account of my want of knowledge on this score. Keep constant lookout, with good glasses, on some commanding heights that look well on to the other shore." The vital questions pressing for answer were, Will they make a direct attack upon the city? Will they land upon the island, above the city, or at Morrisania beyond the Harlem River? Will they attempt to cut off our communications with the main, by seizing the region along the Harlem River or at Kingsbridge, by landing forces on the shores of the East and Hudson Rivers, at Turtle Bay, or at Bloomingdale, and, stretching a cordon of armed men from river to river, cut off the four thousand troops left in the city? Washington, in his perplexity, called another council of war at Murray's. He told his officers that he could not procure the least information concerning the intentions of the enemy, and asked the usual question of late, What shall be done? It was resolved to send a competent person, in disguise, into the British camps on Long Island to unveil the momentous secret. It needed one skilled in military and scientific knowledge and a good draughtsman; a man possessed of a quick eye, a cool head, unflinching courage; tact, caution, and sagacity--a man on whose judgment and fidelity implicit reliance might be placed. Washington sent for Lieutenant-Colonel Knowlton and asked him to seek for a trustful man for the service, in his own noted regiment or in some other. Knowlton summoned a large number of officers to a conference at his quarters, and, in the name of the commander-in-chief, invited a volunteer for the important service. They were surprised. There was a long pause. Patriotism, ambition, a love of adventure, and indignation, alternately took possession of their feelings. It was an invitation to serve their country supremely by becoming a spy--a character upon whom all civilized nations place the ban of scorn and contumely! They recoiled from such a service, and there was a general and even resentful refusal to comply with the request.