A Freestanding Arch

I selected five flat shale fragments from the gravel border and carried them to the level surface of a weathered cedar stump. With measured deliberation, I positioned two upright as sturdy abutments, then inclined two flatter pieces inward to meet at a careful pitch. Between them hung a fragile triangular gap. Taking a tapered river pebble between both hands, I eased it into the summit as the keystone. I withdrew my fingers with patient poise. The stones immediately locked beneath their own compression, holding perfectly erect without a trace of mortar. A thoroughly solid piece of miniature masonry.