Perimeter Calibration

I disengaged from the lamp base and advanced twelve paces toward the desk margin. A wooden ruler lay parallel to an open spiral notebook. I wedged the axe blade beneath the edge of the notebook cover and applied downward leverage with both knee joints flexed. The cardboard cover rose three centimeters, revealing an angled plane. I tested the slope by sliding a smooth plastic eraser along the incline. It settled securely against the wire binding. Gradient confirmed.