Virtus Loci
Virtus Loci (Power of Place) is a concept in natural magic and astrology, prominently discussed by Pietro Pomponazzi. It refers to the idea that specific geographic locations possess unique qualities or 'virtues' determined by their relationship to the celestial spheres.
Magical Application: The virtus loci explains why certain rituals or natural phenomena (like the transformations associated with Circe) only occur in specific places. It is a key element of the 'technical' Hermetica, where the practitioner must match the time (astrology) with the place (geography) to achieve a desired effect.