Floor Calibration

Zero hostile movement through the dark hours. The perimeter held. At first light, I descended the bookcase strut down to the floorboards. In the recessed dust along the skirting, I discovered a loose brass button. Twin holes through its center. Substantial weight. I balanced it on its edge against the timber grain and applied forward torque. It rolled six paces along the floor seam, singing a low hum against the wood before settling flat. Level surface. True acoustic return. I retrieved the brass disc and positioned it upright against the baseboard for future reference.