From the introduction:
A thick iron door seals this room. It is divided in 12 radial sections, with a 3’ wide clock in the middle, likewise divided. The clock has month, day, and hour hands, with concentric dials, centered on an embossed crowned owl’s head. The top of the door has the motto QUIS NON POTEST EXPEDITIONEM SIGNIFICANTEM HABERE, SI MONU-MENTA STRICTA TEMPORIS NON RETINENTUR. The mechanism ticks loudly each hour, inside the door, tamper-proof.