And χθών is the earth (κεχυμένη) spread forth to bigness. And Plectron, according to some, is the sky (πόλος), according to others, it is the air, which strikes (πλήσσοντα) and moves to nature and increase, and which fills all things. But these have not read Cleanthes the philosopher, who expressly calls Plectron the sun; for darting his beams in the east, as if striking the world, he leads the light to its harmonious course. And from the sun it signifies also the rest of the stars.