Welsbach, Baron Carl Auer von (1858-1929), an Austrian chemist. During the 1880's in the laboratory of Robert Wilhelm Bunsen, inventor of the Bunsen burner, he did research on rare-earth elements and their compounds. Von Welsbach noted that some of the compounds burned brilliantly, and he began to use them in gaslight appliances he invented, including the gas mantle. He discovered neodymium and praseodymium (1885), two of the rare-earth elements. In 1907, von Welsbach and G. Urbain (working independently) discovered lutetium and isolated ytterbium, two more rare-earth elements.
He is famous for a phrase he never said, for wearing turtlenecks and for hosting the original 'Cosmos' TV series. As enthusiastic about the stars as he was about marijuana, Carl Sagan led a very surprising life. Here are 10 cool facts.
Albert Einstein was a pretty smart guy. When you look up the word "genius" in the dictionary, so the saying goes, it's a pretty safe bet you'll see Einstein's mug. Think you’re smart enough to take on a quiz about the famed thinker?