The mystery of the nature of these ghosts I may not presume to define; but there are many learned writers of antiquity who believed in their _materiality_, and broached the intricate question of their quality and formation.
The alchymist Paracelsus writes of the _astral element_ or _spirit_—one of the two bodies which compose our nature: being more ethereal, it survived some time after the death of the more substantial form, and sometimes became the familiar spirit of the magician. And what writes Lucretius the Epicurean to illustrate his credence in apparitions? That the surfaces of bodies are constantly thrown off by a sort of centrifugal force; that an exact image is often presented to us by this surface coming off as it were entire, like the cast skin of the rattle-snake or the shell of the chrysalis; and thus the ideas of our absent or departed friends _strike_ on the mind.
The olden chymists, in the age of Louis XIV. accounted for spectral forms by the saline atoms of a putrid corpse being set free, and combining again in their pristine form. Listen, I pray you, to this grave philosophy of an abstruse essay, writ in 1794.
“The apparitions of souls departed do, by the virtue of their formative plastic power, frame unto themselves the vehicles in which they appear out of the moisture of their bodies. So ghosts do often appear in church-yards, and that but for a short time, to wit, before the moisture is wholly dried up.”
“Such are those thick and gloomy shadows damp, Oft seen in charnel-vaults and sepulchres, Lingering and sitting by a new-made grave.”
And we read in the chronicles, that “during the time the ancients _burned_, not _buried_ their dead, there was no such appearance of ghosts as is now.”
Why waves the coarse grass ranker over the grave? It is touched by the larva of the rotting carcase, which, ascending from its putrid chrysalis, a butterfly, or Psyche, flits awhile like an ephemera, and drops again into the vault.
A sentiment something like this, I believe, was the grand cause of the enrolment of the mummies by the Egyptians; for they thought while the body remained entire, the soul was flitting about it: and the early Christians even believed that a portion at least of the soul remained, uncorrupted by the body.