Handmade ion generators
charge the air with negative ions, supposedly to provide spirits with enough energy to properly manifest, move objects, or communicate. Ghost hunters report sudden changes of energy during a haunting, which is how these tools came into play. Measuring ion levels can be difficult
and inaccurate, as ion concentrations tend to vary over short distances, especially indoors. And, of course, connecting a spike in ion levels to a spiritual presence is a leap of the imagination.
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