“We are negative to our guardian spirits; they are positive to us. The whole mystery is illustrated by the workings of the common magnetic telegraph. The principles involved are identical.”
“1. Electric charges attract or repel one another with a force inversely proportional to the square of the distance between them: unlike charges attract, like ones repel.”
One of the four main effects resulting from interaction of positive and negative charges /James Clerk Maxwell in Treatise on Electricity and Magnetism, 1873/
The massive spread of spiritualism in the 19th century could be further explained with the differentiation of spiritualism from other old shibboleths concerning spiritual life and mystical beliefs, which made it plausible to a greater number of people.
To gain more legitimacy and attach a wider range of followers, spiritualists bridged the gap between science and spirituality in a manner which connected them. They had a wide interest in electrical phenomena and were even arguing that the emergence of electromagnetic telegraphy is caused by the spirit world. Thus the whole idea of the terrestrial telegraph became a counterpart of the Spiritual Telegraph.
The term of the “Spiritual Telegraph” was widely popular within the Spiritualist circles. It was basically used to describe a device quite similar to the electromagnetic telegraph, only existing in the spirit world. Inspired by the spiritual telegraph was also the notion of a whole system of spiritual telecommunication systems in the afterlife, all of them based on the ideas of telepresence and disembodied electrical contact. Quite popular was also the notion of technological devices that exist in our world and are based on electromagnetic scientific processes. However, most of those projects featured an energy source or basically a part, that didn’t quite exist in reality, which explains why none of those concepts actually came into being.
Nevertheless, many of the spiritualists used the inventions of the late 19th century to explain the work of the new medium and build around the theory of supernatural presence, whose footsteps could be traced to the roots of electromagnetism. Scientists, mesmerists, writers elaborated their theses about the Spiritual Telegraphy describing it mostly in telegraphic terms. For instance, one of the most prominent defenders of spiritualism was Sir Arthur Conan Doyle, the author of the stories about detective Sherlock Holmes.
Spiritualists described electrical current as a form of “universal fluid” and compared its capacity to shrink time and space with the functions of the terrestrial telegraph. The spiritual world was connected to ours through a medium – a person (in most of the cases a woman) capable of transmitting fluid energies that came from beyond through the body’s nervous system and spreading it further. For spiritualists electricity and body were widely interrelated with the latter one often being described in terms of electrical principles such as current and charge, capacity and resistance, circuit and field.
Of course, the notion of the Spiritual Telegraph and spirit communication had its critics from the beginning. Critics of Spiritualism relied on physics, physiology, psychology and anthropology to disprove spiritualistic assertions. Scientists conducted experiments in which they unveiled more of the spiritualistic “findings” as frauds and trickery. Still, the battle between skeptics and believers wasn’t fair enough – spiritualists used the same tools and branches of science for their conclusions, but had also a wider relation to public because of journalistic sensationalism, gossip, etc.
To sum up, the emergence of the telegraph and the invisibility and intangibility of electrical phenomena opened a “Pandora’s box”, which still can’t be closed. But more about that in the last point: Spiritualism nowadays.