Clingmans Dome, at 6,643 feet, is the highest mountain in Great Smoky Mountains National Park, the highest in Tennessee, and the third highest in the eastern United States. It is named for Thomas Lanier Clingman, an explorer, politician, promoter, and Civil War general who measured mountains there in the mid-1800s. Clingman and scientists Arnold Guyot, Samuel Buckley, and John Le Conte used barometers to measure atmospheric pressure at mountain summits, then compared those readings with measurements taken at the same time from known lowland elevations and applied mathematical formulas that accounted for air temperature, humidity, latitude, and other variables to calculate elevation. Other high peaks in the park bear the names Mount Guyot, at 6,621 feet, and Mount Le Conte, at 6,593 feet. The overlook is named for Charles A. Webb, editor of the Asheville Citizen-Times in the early 1930s, whose influential support helped lead the fight to establish Great Smoky Mountains National Park. Among the six highest eastern peaks, all in North Carolina and Tennessee, Mount Mitchell at 6,684 feet and Mount Craig at 6,647 feet rank above Clingmans Dome, while Balsam Cone at 6,611 feet also joins Clingmans Dome, Mount Guyot, and Mount Le Conte on the list; New Hampshire's Mount Washington, at 6,288 feet, ranks seventeenth in the East.