From 1760 Hemmer was chaplain at the court of Elector Carl Theodor. However, the theologian, mathematician and philosopher devoted all his creative energy to linguistic research and, as head of the physical cabinet, to natural science research. A lightning strike in the stables of Schwetzingen prompted him to study atmospheric electricity. In further development of the lightning conductor introduced by Franklin, the so-called Hemmer's five-pointed star was created. It was installed throughout the Electoral Palatinate, including on the roofs of Schwetzingen Palace, the waterworks, the Garden Mosque and the Marstall, and from here made its triumphal march across the continent. The historic five stars continue to fulfil their task to this day.
