The vignette (fig. 144) that is on the title-page to the Tripus aureus (1618) is a graphic illustration of the double face of alchemy.
The picture is divided into two parts.
On the right is a laboratory where a man, clothed only in trunks, is busy at the fire; on the left a library, where an abbot,”‘ a monk, and a layman” are conferring together.
In the middle, on top of the furnace, stands the tripod with a round flask on it containing a winged dragon.
The dragon symbolizes the visionary experience of the alchemist as he works in his laboratory and “theorizes.”
The dragon in itself is a monstrum—a symbol combining the chthonic principle of the serpent and the aerial principle of the bird.
It is, as Ruland says, a variant of Mercurius.
But Mercurius is the divine winged Hermes (fig. 146) manifest in matter, the god of revelation, lord of thought and sovereign psychopomp.
The liquid metal, argent—”living silver,” quicksilver—was the wonderful substance that perfectly expressed the nature of the: that which glistens and animates within.
When the alchemist speaks of Mercurius, on the face of it he means quicksilver, but inwardly he means the world-creating spirit concealed or imprisoned in matter.
The dragon is probably the oldest pictorial symbol in alchemy of which we have documentary evidence.
It appears as the, the tail-eater, in the Codex Nfarcianus (fig. 147), which dates from the tenth or eleventh century, “together with the legend: h to vav (the One, the All).
Time and again the alchemists reiterate that the opus proceeds from the one and leads back to the one, that it is a sort of circle like a dragon biting its own tail (cf. figs. 20, 44, 46, 47).
For this reason the opus was often called circulate (circular) or else rota (the wheel) (fig. 80).
Mercurius stands at the beginning and end of the work: he is the prima materia, the caput corvi, the nigredo; as dragon he devours himself and as dragon he dies, to rise again as the lapis.
He is the play of colours in the cauda pavonis and the division into four elements.
He is the hermaphrodite that was in the beginning, that splits into the classical brother-sister duality and is reunited in the coniunctio, to appear once again at the end in the radiant form of the lumen novum, the stone.
He is metallic yet liquid, matter yet spirit, cold yet fiery, poison and yet healing draught—a symbol uniting all opposites (fig. 148). ~Carl Jung, CW 12, Para 404