This is what they said: Stairs creaked as if someone was coming down when no one should be there. Objects flew through the air and smashed against walls--especially in the kitchen, where the cabinets had a habit of flying open on their own. Voices spoke to the late night visitor--usually the mournful voice of the mother. Perhaps most frightening of all, looking out through an upstairs window was known to show you a figure, completely black, heading from the field toward the house. Definitely not a place to visit on your own.
People certainly saw bizarre things there when the house was still standing; the following personal account describes a fairly recent visit.
A few of my friends and I were drinking one night and decided that since it was a full moon we should creep each other out. We decided the Potter House was the best place to do this; we've been going there for three years now. We
hopped in the car and drove to Potter Road. We went in through the
front door instead of the side door (which goes into the kitchen). It was
emptier than last time. Last we heard some satanists were sacrificing animals there. We saw some bones laying around.
Next we went into the kitchen. Two people left because of the blood stains on the wall. The other three of us stuck around and went upstairs. In the room to the right there is a huge ANARCHY symbol, which we realized was fresh. We
went into the attic room where the noose is. Then we heard something
and someone swore they saw a figure in the field so we ran. We got
into the car, which was shut off. We were telling the other two what had
happened when the lights just flashed on and a couple of us (three out of five) saw a little girl, kind of transparent, in a white dress. Then the lights went off. When we turned on the car she was gone.
My own visits to the spot, both night and day, didn't bring me face-to-face with anything out of the ordinary, but if you stop by on the right night, you might have better luck.