Argon Argon Argon is a chemical element with symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third-most abundant gas in the Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abundant as water vapor (which averages about 4000 ppmv, but varies greatly), 23 times as abundant as carbon dioxide (400 ppmv), and more than 500 times as abundant as neon (18 ppmv). Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all of the argon in
The Adventure of the Noble Bachelor The Adventure of the Noble Bachelor "The Adventure of the Noble Bachelor", one of the 56 short Sherlock Holmes stories written by British author Sir Arthur Conan Doyle, is the tenth of the twelve stories collected in "The Adventures of Sherlock Holmes". The story was first published in "Strand Magazine" in April 1892. The story entails the disappearance of Hatty, Lord St. Simon's bride on the day of their marriage. She participates in the wedding, but disappears from the reception. The events of the wedding day are most perplexing to Lord St. Simon as it seemed to him that his