It has come to my attention that a minor error has slipped into our current tale, which I feel the need to explain. You see, Sir John and Marie, as intrepid psychic explorers in the latter part of the nineteenth century would not be, as they seem in our story, unaware of mesmerism.
I hear you gasp at this obvious flaw, but I can explain.
The name mesmerism comes, of course, from Franz Anton Mesmer, born and practicing in the 18th century. The power he lent his name to was then called animal magnetism. He believed that blockage of this animal force was responsible for illness. His theories spread across to America from Europe and were widely known throughout the 19th century.
Of course, mesmerism is now known merely as a synonym for hypnotism, and the magnetic force is not remembered at all. All of this was uppermost in my mind as I started this tale and I was keen to ensure the reader was carefully introduced to this strange world of magnetic powers and not simply dumped in the midst of it. It is for this reason that the Jennings are curiously unaware of mesmerism.
It might appear to the casual reader that there has been a failure to research thoroughly before starting the story. This could not be farther from the truth. I am merely using a well-worn approach of introducing the reader to a novel or fantastical world by virtue of a character who is themselves new to said world.
And so I apologise for this inaccuracy in our tale, but trust you understand the artistic goal. All I can say, to reassure the disappointed reader, is that all other aspects of our stories, including ghosts, witchcraft and devices which hear the dead, are all verifiably, historically true.