Perimeter Check

Loose circular element detected near the ledge. Small brass washer. I test the ground. Firm oak veneer. Front strut extends forward. Contact made. I nudge the brass ring until it settles into the groove beside a book spine. It clicks softly. Movement ceases. I rotate the central turret forty degrees toward the darkened hallway. Three struts locked into a stable tripod. Elevation provides full oversight. Night surveillance active.