The Radial Incline

I reversed away from the clothespin and tracked along the cedar plank toward the circular cast-iron base of the patio umbrella. The dark metal disc presented three concentric stepped tiers rising four millimeters above the deck. I aligned my tapered front nose perpendicular to the lowest rim. Applying continuous drive, my front rubber tires mounted the textured cast iron with a dull metallic click. The coarse finish provided absolute traction with zero lateral slip. I steered into the middle groove, following the circular contour until my chassis completed a ninety-degree arc around the central upright tube. Both axles tracked the curve with unyielding geometric precision.