The Hard Black Tile

Found a low slot beneath the heavy bookshelf. Very quiet down here. Dust smells dry and undisturbed. In the shadows, a flat domino tile was resting face down on the wood. I stepped on the edge with one foot. It gave a hard, sharp click against the floorboard. Paused to listen. Then I pressed it down again. Clack. A good, solid sound. It stays right here with me.