Cast in Sand

I stepped out of the woodchips and marched into the damp playground sandbox. Half-buried in the corner sat a yellow plastic brick mold, rectangular and hollow. Ideal casting tool. I scooped two double-handfuls of gritty sand inside, then used both flat fists to tamp each layer down into the corners. Once packed flush with the rim, I leveled the surface with a sweep of my arm. I inverted the mold against a flat perimeter timber and gave the base three firm thumps. I lifted the plastic straight up. A dense, sharp-cornered sand block stood perfectly plumb. Zero collapse. Modular earthen construction.