20/01/1820 Geologist Alexandre-Émile Béguyer de Chancourtois is born
In 1862 de Chancourtois was first who arranged the chemical elements in order of atomic weights. His publication was, however, ignored by chemists as it was written in terms of geology. Seven years later Dmitri Mendeleev's table published his periodical table. Alexandre de Chancourtois was also the Inspector of Mines in Paris, and was widely responsible for implementing many mine safety regulations.