THE DISCOVERY OF THE ELEMENTS. XI. SOME ELEMENTS ISOLATED WITH THE AID OF POTASSIUM AND SODIUM: ZIRCONIUM, TITANIUM, CERIUM, AND THORIUM*
The earths of the titanium group had a cosmopolitan origin. The German chemist, Klaproth, discovered zirconia in 1789 while analyzing a zircon from Ceylon. Two years later the English clergyman, William Gregor, found ritania, or "menachanitr," as he called it, in a black sand from his own Mrish in Cornumll, but announced his discovery in such a modest manner that i t made little impression on the scient