Measuring the Depth of a Well with a Quadrant

This monochromatic print depicts a cylindrical well viewed from an elevated angle, showing its stone rim and a wooden bucket resting on the edge. A quadrant is perched on the side of the well, with a plumb line hanging vertically and a sighting line projected downward in a dashed line that forms a triangle with the well's interior wall. Below the ground level, the well’s submerged shaft is rendered in phantom dashed lines, illustrating the mathematical calculation of its depth. The style is that of a 17th-century woodcut or etching, characterized by cross-hatched shading and precise, diagrammatic linework.

This image originates from Robert Fludd's 'Utriusque Cosmi Maioris scilicet et Minoris metaphysica, physica, atque technica Historia' (1617–1621), a foundational text of the Rosicrucian period that attempts to unify macrocosmic and microcosmic knowledge through geometry, music, and natural philosophy.