Thunder and lightning have long been interpreted as the divine might of gods as they sent their rage and flames down to Earth. All manner of precautions, from consecrated mullein plants, lightning amulets, and pleas – were supposed to prevent the worst. “Oh, holy Saint Florian, protect our house and take another.” In the meantime, Benjamin Franklin (1706 – 1790) – inventor, natural researcher, and co-author of the American Declaration of Independence – had long since proven that weather is in fact based on electrical discharges, and thus an entirely rational phenomenon. In a series of spectacular experiments, Franklin is supposed to have captured the electricity of a lightning strike with a kite, and then started his initial experiments with lightning conductors.
This thunder house from the Physical Cabinet of the former Jesuit-run Gymnasium Tricoronatum presented curious students in the late 18th century with a miniature that functions as a lightning conductor: The electrostatically generated lightning strikes the brass bearing on the chimney, and is led through a wire along the wooden outer wall to the ground. If the grounding is capped, the energy from the spark causes a wooden block above the door to jump out in a manner reminiscent of an actual lightning strike. The block has survived all manner of experiments, but not the centuries. It is now lost. The thunder house is currently on permanent loan from the Kölner Gymnasial- und Stiftungsfonds to the Kölnisches Stadtmuseum.
Rüdiger Müller