Many years ago I read a story of a man who experimented with a magnet strapped to his forehead. From what I remember, he examined this experiment in his attic study. He harnessed a magnet on his forehead for what I believe was an hour per day.
After a time, he noticed a ghostly boy running through his study. Then, his world was immersed within another, noticing a young man and a woman sitting next to a tree. A final vision of the same man and women, but this time they actually notice him also and seem frightened.
I can't recall if this was a fiction or some actual claim of an experiment. I've been trying all over the web to find it with no luck.
Edit: Adding as many details as I can. I'm having trouble remembering everything about it but I'll try my best.
The age of the story: Really foggy on this but I want to say between the 1850s and the early 1900s.
Medium, read online, was definitely a shorter story. If printed would be maybe just a few pages.
Time when the story was read: I read this story online about 15 years ago. I can't remember the website or the format of the site.
Language of the story: English (possibly from the US). I believe the subject in the story was some kind of a self-proclaimed modern philosopher.
Location: I am from the US but given that I read it online and I'm foggy with the details, the origin could have been from elsewhere.
The appearance of the book: There where no photos or scans of an actual book.