Paul-Emile Lecoq de Boisbaudran
DOI: 10.1063/PT.5.031200
Today is the birthday of chemist Paul-Émile Lecoq de Boisbaudran who was born in 1838 in Cognac, France. De Boisbaudran was partially self-taught, using books from the courses of the École Polytechnique. The laboratory he created allowed him to reproduce many of the experiments in the books where he focused on studying the spectra of rare earth elements. Working there, he discovered a number of elements including gallium, samarium, dysprosium, and europium (though he is not generally credited as the discoverer of the last because he was not able to isolate it). He also was the first to suggest that the recently discovered element argon was a member of a then unknown chemical series of elements now known as the noble gases.
Date in History: 18 April 1838