To Sum It All Up...
You guys did well analyzing this image and got most of the major aspects of it. I just want to post a complete description in case people stumble upon this page while googling and want to know exactly what the image contains.
There is a snake and winged serpent or basilisk in a ouroborus shape. These represent the elements Air and Earth. Showing them together as a ouroborous signifies the union of opposites. (This is very similar imagery to what the Egyptian Pharaohs all wore on there headdress, a vulture and a cobra, representing Upper and Lower egypt, air and earth, the union of opposites.) They are both wearing crowns, symbolizing they rule their two domains.
Volatile and Fixum refer to these air and Earth figures, one is movement, the other unmoving, fixed. I think the best translation for these two words in this context would be "momentum" and "inertia".
In the middle is the Seal of Solomon which is a triangle and an upside down triangle representing the elements Fire ▲ and Water ▼ merged. So again, it is the union of opposites. Now we have all 4 basic elements represented. Air, Earth, Water, Fire.
Around the Seal of Solomon we have the 7 heavenly bodies, the planets. Each Planet also represents a metal and of course a god.
Gold - Sol ☼ (Apollo)
Silver - Luna ☽ (Artemis)
Copper - Venus ♀ (Aphrodite)
Iron - Mars ♂ (Aries)
Tin - Jupiter ♃ (Zeus)
Mercury - Mercury ☿ (Hermes)
Lead - Saturn ♄ (Cronus)
Mercury is in the middle, which might surprise the modern reader who would naturally put the Sun in the middle. However Mercury (the element) was very important to the alchemists because it had a duel nature that fascinated them.
"For the alchemist, quicksilver (mercury) meant the concrete, material manifestation of the spirit Mercurius"... "Mercury has two forms "mercurious crudus or vulgi" (crude or ordinary quicksilver) and "mercurious philosophorum (the spiritus mercurialis or the spirit Mercurious, Hermes-Nous) who hovers in the sky as the golden lightening-snake or Nous Serpent."
C.G. Jung Collected Works Vol 9. Part 1. Paragraph 554.
This also ties the ouroborous image on the outside into mercury in the middle. "Mercurius forms a word-encircling band"..."Mercurius is a serpent or dragon in alchemy ("serpens mercurialis")". .." According to the old view mercurius is duplex, i.e. he is himself an antithesis. Mercurious or Hermes is a magician and god of magicians... His magicians wand, the caduceus, is entwined by two snakes"
C.G. Jung Collected Works Vol 9. Part 1. Paragraph 553.
So far we have very strong "union of opposites" or "Mysterium Coniunctioni" imagery, much like a western "Ying Yang" symbol. What else do we have?
Inside the Seal of Solomon are animalia (animal), vegetabilia (vegetable) and Mineralia (mineral); mare (sea), terra (land), Ros Pluvia (dew rain) . So we have again, basic classifications ( if we take "dew rain" to refer to the sky, clouds, etc). Dew refers to a singular drop while pluvia is the multiple rain.
Ros Pluvia is above and mineralia is below, perhaps hinting at the dual nature of mercury which is both mineral and liquid. Either way Ros Pluvia is a slightly odd term, but it does fit in with the next part:
"abyssum abyssus invocat" is a biblical verse "the deep calleth the deep" which is Psalms 42:8. (The image even says Ps 42:8)
http://www.bible.is/LTNNVV/Ps/42/8
This quote is about the sound of falling water, so may relate to the "ros pluvia"? But more deeply, how the "opposites" call to each other and long to be joined and integrated into one-another.
Abyssus Superior and Abyssus Inferior which means Upper Void and Lower Void. I am not really sure, it's a stretch but could it be heaven and hell? Abyssus is often mistranslated as hell. I'm not really sure, but again it does reinforce the motif of opposites.
Thats all I got for this image. Thanks for posting it!