Gas Chemistry Development By nate1 1766 The element Hydrogen Found by Henry Cavendish 1772 The element Nitrogen Found by Daniel Rutherford 1868 The element Helium Found by Pierre-Jules-Cesar Janssen 1898 The element Krypton Found by Sir William Ramsay & Morris M. Travers 1898 The element Neon Found by Sir William Ramsay & Morris M. Travers