The inverted triangle in the Hourglass (The Collective’s Rhune)
Aristotle established triangles as symbols of the five elements in nature, key aspects of the hourglass book.
The usual form is of a triangle, circumscribed with various words of power. … The alchemical/magical symbol for water is an inverted triangle, symbolizing downward flow.
The downward-pointing triangle is also an ancient symbol of femininity, being a representation of female genitalia.