At least four different paintings by Lukas Cranach that represent melancholy are known today. They all show Melancholia as a female, winged figure and were clearly inspired by Albrecht Dürer’s famous engraving. Cranach added two new major elements, however: little children who are peacefully playing, and dark clouds or trails of smoke with naked women riding on animals, presumably witches, and other demonic figures. Historians have convincingly interpreted these demonic elements in the light of Luther’s notion of melancholy as a “devil’s bath”. As this paper argues, they have missed a major point, however. The demonic figures in the dark clouds gave visual expression to the contemporary medical understanding of melancholy as a disease, rather than a melancholic temperament. The disease “melancholy” was characterized by delusions, by fury and frenzy or else despondency and was not attributed to a predominance of black bile in the body but to morbid, adust, blackish humors that were generated from one of the four natural humors. They released dark vapors and fumes which ascended toward the head, disturbing the workings of the brain and causing delusions. This, the paper argues, was the idea behind the dark clouds in Cranach’s paintings. The melancholic fumes rise toward Melancholia’s brain. They make her believe that there are demons around her and prompt her to join them, to carve a stick for the ride to the Venus mountain, while the children around her play unperturbed.