LukeM wrote:John, in my scraping the internet for answers, I found more than one person that claimed both dye and ping pong ball tests have been performed. Someone also claimed that a local university was having (or had) students design some sort of electronic instrument to explore the hole.
LukeM wrote:Hmm, I might have to try to get in contact with someone at the department of Geology at the University of Minnesota. The original article I linked references info originating from a geologist there.
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