Stories from Physics for 11-14 14-16
In 1778, the German physicist Georg Christoph Lichtenberg built a large electrophorus, a capacitor-like device charged by rubbing with fur or cloth. When he first tested the instrument, it had not been cleaned, and was covered in powder left over from polishing.
In a paper, Lichtenberg described:
Much to my great joy, it [the powder] gathered to form little stars, dim and pale at first, but as the dust was more abundantly and energetically scattered, there were very beautiful and definite figures, not unlike an engraved design. Sometimes there appeared almost innumerable stars, milky ways and great suns.
The branching patterns generated by electrical discharges became known as Lichtenberg figures. Lichtenberg figures are observed on the skin of some victims of lightning strikes.