The name Ouroboros refers to the serpent biting its tail, the oldest example of which dates from Egypt around 1600 BCE, one of the oldest examples being from the Tomb of Tuthmosis III. A much older similar design is found carved in Jade in the Hongshan culture of ancient China between 4700 – 2900 BCE, but did not bite their tails.
The symbol most likely entered Hermetic alchemy directly from Egyptian culture, or via its use by the Gnostics. In either case it can symbolise eternity (Time-Without-Age?), regeneration/reincarnation and a self contained system. The alchemists are also said to have used it to represent the cyclical nature of their work.
Hen to Pan
One of the most famous and oldest depictions of the Ouroboros in Hermetic tradition is found in the Chrysopoeia of Cleopatra, encloses the words hen to pan which is Greek for 'One, the All'. Examples from ancient Egypt sometimes enclose a Scarab.
Johannes Macarius talks of the Ouroboros, the Scarab and hen to pan in Abraxas en Apistopistus.
The scarab, the holy “ball-roller” of the Egyptians, embodies the self generating T-shaped, hermaphrodite principle of Sun-Osiris and Moon-Isis. Both, the Ouroboros and the Scarab are an expression of the 'hen to pan', the eternal transformation of the Ever Unchanging.