Alchemical Symbolism in the VMS

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Johann Grasshoff, Dyas Chymica Tripartita, 1625, SLUB Dresden, Bibl.Sud. 725, You are not allowed to view links. Register or Login to view. .

The central part of the illustration ( earth cave ) shows either the 9 (3 + 6) muses or 3 female characters + 7 classic planets. There are different interpretations. In any case, Apollo sits in the middle of the sevens group. Any hints?

The text below contains usual Hermetic dictum: "As above, so below", and (approximately) "what is inscribed in the sky - takes place on the Earth. Fire, Water and they both flowing oppositely, that give fruits, when they unite, let you better know!"
So I think, the upper part shows exactly fire, water and the "water of fire" (that produces "aurum potabile"), below part contains seven planets or rather their projections on the Earth. 
Why Appollo, but not Mercury?