Pepper's ghost: the glass spectre of the nineteenth century
Henry Dircks, John Henry Pepper and Christmas 1862: how a sheet of glass brought ghosts onto the Victorian stage, in the footsteps of Della Porta.
On the evening of 24 December 1862, at the Royal Polytechnic Institution in London, the audience watched a scene taken from a Christmas story by Charles Dickens, The Haunted Man. On stage a flesh-and-blood actor conversed with a transparent spectre, which appeared, moved and vanished into thin air. No one in the hall understood how it was possible. An illusion had been born that would become famous as Pepper's ghost.
An ancient idea
The optical principle on which it rested had been known for centuries. Giovan Battista Della Porta, in his Magia naturalis, published in Naples in 1558 and enlarged in 1589, already described how a sheet of glass could show images of hidden objects, superimposing them on what was seen through it. For Della Porta, as for many Renaissance authors, natural magic included precisely such secrets of nature, capable of producing wonder without the intervention of demons.
Glass is in fact both transparent and reflective. If an inclined sheet is placed between the audience and the stage, and a figure hidden in a pit in front of the stage is brightly lit, its reflection appears superimposed on the scene, like an evanescent image. By adjusting the light the figure appears and disappears; by switching it off completely, it vanishes.
Dircks, Pepper and the dispute
In 1858 a Liverpool engineer, Henry Dircks, presented a device based on this principle, which he called the Dircksian Phantasmagoria. His design, however, required theatres to be rebuilt and found no buyers. John Henry Pepper, a chemist and popular science lecturer who directed the Polytechnic, saw how to adapt it to an existing stage, tilting the glass and hiding the ghost actor below stage level.
The two filed the patent together in 1863, but almost all the fame went to Pepper, and the illusion's name still recalls him. Dircks complained publicly in his book The Ghost, published the same year. Meanwhile the show was imitated in theatres across Europe and became an attraction of music halls and fairs. In Paris and other cities plays were written specially to exploit the effect, with avenging spectres, apparitions of the dead and skeletons coming to life beside the actors.
Ghosts and spiritualism
The success of Pepper's ghost coincided with the great season of spiritualism, born in the United States in 1848 with the Fox sisters and soon spread to Europe. Séances promised apparitions of the dead, and illusionists responded by showing that those same apparitions could be created by optical means. Pepper presented his illusion as a science lesson, but the public experienced it above all as a thrill.
The principle has never been abandoned. It was used in nineteenth-century theatres for ghost dramas, in amusement park attractions and, in updated versions, in many contemporary shows that make luminous figures appear on stage. From Della Porta's natural magic to the Victorian theatre, Pepper's ghost reminds us that the history of stage apparitions is also a history of optics and of its power to deceive the eye.