Tellurium was discovered in 1782 by Baron F. J. Müller von Reichenstein, and selenium was discovered
in 1817 by Berzelius. The last member of the group was discovered in 1898 by Madame Curie, and the
name polonium comes from her native country, Poland. The name tellurium comes from the Latin tel-lus, meaning “ earth, ”and selenium is named from a Greek word, selene, meaning “ moon. ”Compounds
containing sulfur also contain small amounts of selenium and tellurium, and this is the major source of these elements. In the electrolytic refi ning of copper, the anode sludge contains some selenium and tellu-rium. Sulfur is obtained from vast deposits of the element that are found below the surface in Louisiana
and Texas by the Frasch process, which makes use of three concentric pipes. In this process, sulfur (which
melts at 119°C) is melted by superheated water forced underground in one pipe while compressed air is
forced down a second pipe. The molten sulfur is forced to the surface through the third pipe.