19th C. French Noonday Cannon

A miniature cannon mounted on a circular stone sundial base, the hour lines incised in radiating bands across the surface with a small gnomon peg set at center. Two iron uprights rise from the base to hold a magnifying lens, angled toward the cannon's touch-hole. The ironwork is matte black throughout, the stone pale and worn at the edges.

The mechanism is straightforward and ingenious: as the sun crosses the meridian at local solar noon, the lens focuses sunlight onto the touch-hole and fires the cannon automatically. The sundial orients the device; the cannon marks the moment. Originally calibrated for a specific latitude, the lens angle would need adjusting for use anywhere else.

Style: French Scientific Instrument
Materials & Techniques: Cast iron, stone, glass lens
Place of Origin: France
Period: 19th C.