Demonstration of Solar Air Expansion

An engraved scientific illustration depicts a physics experiment set against a rudimentary landscape featuring a distant town and sea. A large, sun-radiating face in the upper right corner directs light toward a spherical vessel labeled 'A' (a 'Pila plumbea'), which is connected by a bent tube ('Tuba inflexa', 'E') to a water-filled jug ('Olla', 'C'). The composition includes internal labels keyed to a list at the bottom, explaining the mechanism of atmospheric density and liquid displacement through solar heating.

This image originates from Robert Fludd's 'Utriusque Cosmi Maioris Scilicet et Minoris Metaphysica, Physica atque Technica Historia' (1617). It reflects the early modern transition toward experimental natural philosophy, attempting to visualize the unseen forces of air pressure and thermal expansion within a Hermetic cosmological framework.