Röntgen's other experiment.

Abstract

Röntgen's fame today rests solely on his discovery of X-rays and takes no account of the fact that he was perhaps the leading experimental physicist of his time. One experiment he devised and brilliantly executed was, arguably, one of the most important of the 19th century. It was greatly celebrated at the time, yet today has been all but completely forgotten. With the aim of developing a more complete picture of Röntgen and his place in the history of physics, this paper describes the nature of the problem he tackled and gives an outline of his experimental approach to it. The significance of his achievement for the construction of the edifice of 19th century physics is explained.