Excerpt from "The Haunted Tourist: A Layman's Guide to Ghost Hunting and Hauntings In Northern California" by J.D. Woodall
What are ghosts? Theories abound. A literate discussion about ghosts leads naturally to rumor, hearsay and innuendo, as well as philosophy, religion, mythology, history, folk-tales, and physics. Most researchers agree that ghosts, spirits, apparitions, et al., are the electromagnetic residues of a once-living being. The experts' theory is that energy is neither created nor destroyed, but can be transformed. That transformation of energy after the death of the physical body exists in the form of ghosts. In short, a ghost is a person's lingering personality, hopes, dreams, desires, soul, memory, and all those things which made that person so unique while he or she was still alive.
There is evidence on film and on audiotape that ghosts do, in fact, exist. There are a lot of photographs showing unusual, round, milky white bubbles floating over tombstones or over the heads of other people in the photographs. There are also photographs of smoke like ghosts, misty ghosts, and half-transparent apparitions which were not there when the pictures were taken, and which only show up on film or videotape. The good news is that the living people present in the photograph, videotape or audiotape are not aware that there is a ghost standing next to them. Personally, I wouldn't want to know either. Ghosts don't seem to be limited only to human beings. There are reports of ghostly dogs and cats who haunt houses after they have died. There are even reports of household pets who sometimes haunt a location with their owners after the owners become ghosts themselves. There are also reports of ghostly pack mules, spirited horses, and wild black panthers that haunt the hillside and then disappear. And even more strange are the tales of ghostly ships which can be spotted docked at the pier or sailing into the foggy bay. And who hasn't heard tales of phantom trains and stagecoaches, the mournful whistles and clatter of which can be heard in the lonely darkness of the night?