The Devil Piercing the Eagle in the Vessel

The image features a purple, hybrid creature with pointed ears, human-like limbs, and a long, curving tail standing on the left. It holds a sheathed sword in its right hand and a large, barbed arrow in its left. To the right, a white-walled vessel or crucible sits atop a bed of bright orange and yellow flames, containing a black, eagle-like bird huddled inside. The background is a solid, flat green.

This illumination is from the 'Aurora Consurgens', a 15th-century alchemical treatise attributed to a pseudo-Thomas Aquinas. The eagle in the vessel represents the process of distillation or the 'volatilization of the fixed,' a key stage in the alchemical Magnum Opus.