Then, as to the impositions of the priesthood. In Naples was the blood of Saint Januarius concealed in a phial, and on certain solemn days this so called blood really became liquified; but it was effected secretly, by chemical means; and I remember, the archbishop who confessed the secret to the French general Championet, was exiled by the Vatican.
In the reign of Henry VIII. too (I quote from Hume), other bloody secrets of this sort were unfolded. “At Hales, in the county of Gloucester, there had been shown during several ages the blood of Christ brought from Jerusalem; and it is easy to imagine the veneration with which such a relic was regarded. A miraculous circumstance also attended this relic. The sacred blood was not visible to any one in mortal sin, even when set before him; and, till he had performed good works sufficient for his absolution, it would not deign to discover itself to him. At the dissolution of the monastery the whole contrivance was detected. Two of the monks, who were let into the secret, had taken the blood of a duck, which they renewed every week; they put it in a vial, one side of which consisted of thin and transparent crystal, the other of thick and opaque. When any rich pilgrim arrived, they were sure to show him the dark side of the vial till masses and offerings had expiated his offences, and then, finding his money, or patience, or faith, nearly exhausted, they made him happy by turning the vial.”
But there is no end to relics in Italy. Even two hundred years ago, John Evelyn makes out this catalogue of those he saw in St. Mark’s, at Venice.
“Divers heads of saints, inchased in gold; a small ampulla, or glass, with our Saviour’s blood; a great morsel of the real cross; one of the nails; a thorn; a fragment of the column to which our Lord was bound when scourged; a piece of St. Luke’s arm; a rib of St. Stephen; and a finger of Mary Magdalene!”
Among the more innocent illusions of art, I may remind you of concave and cylindrical mirrors and lenses, the magic lanthorn, “les ombres chinoises,”and the phantasmagoria of Cagliastro, by which daggers appear to strike the breast of the spectator, and images of objects in other rooms are thrown on the walls of that in which we are sitting. A mirror, thus accidentally placed, has afforded the evidence of murder within our own time.
The duration of impressions on the eye, is another source of illusion. An image remains on the retina, I believe, about the eighth of a second; as it departs, if another object supplies its place in quick succession, the two images form, as it were, a union, and become blended. A knowledge of this law, in the ages of blind superstition, would have placed an overwhelming weapon in the hands of priestcraft; in our day, it is the source of rational and innocent pleasure, by the invention of optical toys.
The whisking of an ignited stick produces a fiery circle—why? Because from excessive rapidity the rays from one point remain impressed on the retina, until the revolution completes the circle.
The Thaumatrope, or wonder-turner, and the Phantasmascope, are ingenious illustrations of this law of impression; so also is the whirling machine, which so beautifully evinces the fact of white being compounded of all the prismatic colours, blended in certain proportions. The prismatic Iris is painted on a revolving circle; by excessive rapidity of revolution, the colours are actually blended (as if mixed in a vessel) on the retina, and the surface of the machine is white to the eye.
To these may be added the combustion of phosphorus and other substances, in oxygen: red, green, and blue lights, which change the angel face of beauty into the visage of a demon; and the inhalation of noxious fumes and gases, creating altogether a new train of phantoms in the world of experimental magic, and developing the formerly occult mysteries of the art of incantation.
Chance may also involve a seeming mystery of very awful import. Some years ago the town of Reading was thus bewildered. On the loaves were seen the most mysterious signs. On one, a skeleton’s head and cross-bones; on another, the word “resurgam;” on another, a date of death was marked in deep impressions. The loaves of course were, by some mysterious influence, the vehicles of solemn warning from the Deity.