The Loose Screws of Freiburg: the Vigelius-Schule Cellar Poltergeist

March 1966. The Vigelius-Schule in Freiburg-Haslach was still being built. In the cellar, electricians were laying cables. For a cable tray, they fixed many metal hooks into the cement walls. Each was set the same way. A hammer drill made two 8 mm holes. Two plastic dowels went in, and two screws held the hook. One later account says the screws were 9 cm long and the brackets had passed a strong load test.

The foreman noticed it first. Almost immediately after the hooks were fixed, the screws worked loose. Hooks he had used for pull-ups, his own load test, could later simply be pulled out by hand.

The next day, several observers saw seven hooks come out of the wall, dowels still attached. Then came the strangest report. One hook is said to have flown after the apprentice as he walked along the corridor. In a curve.

The apprentice was 15 years old. According to a 2021 account, his mere presence was enough to bring the brackets out of the wall. He only had to stand in front of them and look at them. No one from the electrical firm had touched them.

Hans Bender and the team of his Institut für Grenzgebiete der Psychologie und Psychohygiene, the IGPP, took up the case. With some other observers, they ran a test by "erwartender Beobachtung", expectant observation. Two hooks were freshly fixed and checked for firmness. The apprentice stood one metre from the wall. Within two minutes the screws were loose, though nobody saw them move.

Flash photographs and tape recordings were made. Two days later, the team tried to film. This time the hooks stayed fixed.

Bender presented the case in "New Developments in Poltergeist Research", his 1969 presidential address to the Parapsychological Association in New York, with a German version in 1970. It became known as the "Phänomen der lockeren Schrauben von Freiburg", the loose screws of Freiburg. The brackets and the case files are kept in the IGPP archive.

No verdict was ever reached. In 2021, the magazine chilli Freiburg wrote that the cause was never really explained. No confession or exposure is known. Still, the period casts a shadow. Bender's Bremen porcelain shop case of 1965 also centred on a teenage apprentice, Heiner Scholz, who confessed in 1978 to faking the phenomena. Nothing ties Scholz to the Freiburg cellar.

Fraud is the leading ordinary explanation for poltergeist cases in general. It was proven in 8% of the cases sampled by Alan Gauld and Tony Cornell. The skeptic Joe Nickell argues most are pranks by children around puberty. Others point to suggestion, expectation and errors of perception.

In 2020 the case found new readers in Freiburgs Gespenster, a collection of 43 Freiburg haunting entries by Uwe Schellinger and Michael Nahm, written for the city's 900th anniversary. A close parallel followed in Rosenheim from 1967, where electricians found fluorescent tubes turned in their sockets in another of Bender's cases. In Freiburg, the hooks are still in the archive. The question is still open.