Leaving the manager, as if he were going up to the Woodmans’ apartment, Ellery resumed his prowl. On the ground floor he speedily discovered there was no possible means of exit except the main door. There remained the basement, occupied mainly by a vast grill room which was closed at ten o’clock. Ellery descended the stairs, and pushed open the grill room door communicating with the hotel. The place was in darkness and, without turning on the light, he made a tour of the huge room. At the far end were cloak rooms and another flight of stairs communicating with the street. So far it would be fully possible for a guest to make his way without attracting attention. Ellery went up the far stairs, and approached the door leading from the grill room to the street. It was heavily barred and bolted, as well as locked. But the key was in the lock, and there seemed to be nothing to prevent the bolts from being withdrawn from the inside. As quietly as he could Ellery took down the bars, slid back the bolts, and unlocked the door. He stood, not in the street, but in a small outer hall with another locked door in front of him. This door also could be undone from the inside, and, opening it cautiously, Ellery found himself looking out into St. John’s Street. He had established the fact that it was possible at night for a guest to leave the Cunningham Hotel unobserved. Quietly he re-locked the doors and slid back the well-oiled bolts and bars, surprised for the second time to find how little noise his operations made. Woodman, then, could have both left and returned to the hotel without being seen. But had he? The very lack of possible observers seemed to make it impossible to prove the case either for or against him. If no one had seen Ellery make his investigations—and as he returned to the ground floor he was certain that no one had noticed him, at least until he reached the top of the basement stairs—why should any one have seen Carter Woodman when he had followed the same route? The effect of Ellery’s investigations was to make Woodman’s _alibi_ insecure. But it afforded absolutely no positive evidence of his guilt. Still, it was something to have shown that the _alibi_ was not conclusive, and Ellery was fairly well pleased with the result of his visit. But he had not yet done. According to Woodman’s story, he had written his letters in a small and little used writing-room on the first floor, at the opposite end of the hotel from his own rooms, but quite near the basement stairs, to which another small flight of stairs led directly from the first floor almost from the writing-room door. Ellery went into the writing-room and found it deserted. He remembered that Woodman had stated that he had had it to himself throughout the time he had spent there.