a celebrated mountain of the Equatorial Andes, in S. Lat. 1° 30', W. Long. 79°, and long considered the highest in the known world. It is 21,424 feet high. It was ascended by Humboldt and Bonpland in June 1802 to the height of 19,286 feet; and again by Boussingault in December 1831 to 19,689 feet.