The only way out of the cavern is along a narrow ledge overlooking the gulley you came down earlier. You edge your way along it as carefully as possible, but unfortunately you are about as good at balancing as a high-wire hippopotomus and a summit meeting with the ground soon looks inevitable. Fortunately you topple backwards instead of forwards, crashing through the thin plasterboard wall of the gulley and into a narrow passage used as a conduit for gas pipes and electrical cables. After walking through several boring corridors, you find yourself in a north-south passage with an exit to the east. A sign poiting north reads: TO THE LABORATORY. To go north, click here. Otherwise you can go east; click here, or up through a trapdoor in the ceiling accessed by a ladder.