"As the dream stuff dissolves
into a massa confusa, it also darkens in color until it becomes black like the
vilest of scoria. When the alchemist saw the changing color of the metals, he knew the
first true transformation was taking place in the microcosm of the vessel. The alchemists
termed this stage in the work the nigredo. Paracelsus says that the sages knew
the blackness as the Raven, Crow's Bill, and Ashes of Hermes' Tree." R.
Sevenson, "The Alchemy of Dreamwork: Reflections on Freud and the Alchemical
Tradition." Dragonflies. Spring 1979. p.108.