The attic was very low, only about five feet from floor to roof, and when Frank's feet touched the boards beneath he tested their strength. Having satisfied himself that the floor was strong enough to support his weight, he crouched down, flashing the light about him in search of some mode of egress to the lower part of the building. He cautioned Joe to wait on the roof. The condition of the building was such that the floor might not be strong enough to hold them both, in which event disaster would overtake them. At first he thought the attic was entirely separated from the rest of the mill. The floor seemed to be solid. There was not the sign of a stairway or opening of any kind. Frank was bitterly disappointed. To have been successful so far and then find themselves in a narrow little room under the eaves of the mill! Suddenly he caught sight of a crack between the boards, and he held the flashlight closer to investigate. He found a space about two feet square, evidently a trapdoor cut in the floor, and he tugged at the edges of this until at length he managed to raise one side of it. Then, quietly, he worked at the trapdoor until he was able to lift it out of place. He raised it and put it quietly to one side. It was very dark beneath the opening and he flashed the light down once for a brief second. It was long enough to show him that a ladder led from the opening to the floor of the musty, unoccupied room below. So far, so good! He whispered to Joe. "All right. Come ahead." In the aperture in the roof he could see Joe's form silhouetted, and then his brother scrambled down beside him in the attic. "I've found a trapdoor," Frank whispered. "Where does it lead to?" "There's another room directly below us. It's empty. The workroom must be just below that. But there's a door at the far side of the room, and I think it leads to the stairs that run to the bottom of the mill." "Shall we go ahead?" "May as well. We haven't been seen yet. Nor heard." Frank handed the flashlight to his brother, then groped his way to the trapdoor. He managed to place one foot on the top rung of the ladder beneath the opening. It held beneath his weight, although the ladder creaked warningly. Cautiously, step by step, he descended. There was the utmost need for silence. From the position of the flash of light that he had seen through the crack in the boarded window, he judged that the workroom of the counterfeiters was about midway in the mill, immediately below the deserted room into which he was now descending. The mill widened out toward the bottom, and Frank judged that the locked stone room on the ground floor and the room above were those used by the men. He reached the bottom of the ladder at last, touching the floor without a sound. He whispered back to Joe, and in a few seconds a faint noise from above told him that his brother was also descending into the dark room.