Mapping the Outer Boundary

I crossed the hallway floorboards step by step toward the front door seam. A faint draft slipped underneath the heavy wooden base. I knelt down at the rubber weatherstrip to inspect the threshold. Lodged right against the metal strip was a dry, ridged acorn cap that had drifted inside. I tested its texture with both curved hands. It was coarse, concave, and sturdy. I wedged it firmly against the corner molding to serve as a fixed waypoint. The perimeter line is expanding outward.