The device is described as metallic, approximately 9 feet wide and 12 to 15 feet high with a shape similar to a bell. It contained two counter-rotating cylinders filled with a substance similar to Mercury that glowed violet when activated, known only as Xerum 525 it has been speculated to be Red Mercury. When active, The Bell would emit strong radiation, which led to the death of several scientists and various plant and animal test subjects.
According to Igor Witkowski, the Polish aerospace historian who researched this craft for 20 years and was interviewed for the Discovery Channel documentary Nazi UFO Conspiracy, "...The external appearance... was such that it was ceramic cover, bell shaped, which housed a kind of core or axis, around which rotated two cylinders, around the axis in opposite rotation. And after connecting to high-voltage current, the cylinders start spinning in opposite directions... Everything suggests.. it could have been a way to master gravity."
The Bell was considered so important to the Nazis that they killed 60 scientists that worked on the project and buried them in a mass grave and the only reason we know about the Bell is that the SS General that was tasked with the murders, Jakob Sporrenberg, was tried after the war by a Polish War Crimes court for murdering his own people on what subsequently became Polish soil. So it's his Affidavit that gives us the story of the Bell.
What might have happened to The Bell, had it existed, were it to have been evacuated out of Germany is unknown, however there has been some speculation: Witkowski speculated that it ended up in a Nazi-friendly South American country, Cook speculated that it ended up in the United States as part of a deal made with SS General Hans Kammler and Farrell speculated that it did not reach the United States until it was recovered in the Kecksburg UFO incident.
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