The vigil on the stairs descended to take their posts. Four monks manned the treadmill. The fifth monk hovered over the dynamo. The sixth monk climbed the shelf-ladder and took his seat on the top rung, his head bumping the top of the archway. He pulled a mask of smoke-blackened oily parchment over his face to protect his eyes, then felt for the lamp fixture and its thumbscrew, while Brother Komhoer watched him nervously from below.