The Great Trigonometrical Survey of India officially…
March
1856 CE
The Great Trigonometrical Survey of India officially gives 'Peak XV' (later to be named Mount Everest) the height of 29,002 feet (8,840 meters) in March 1856.
'Peak IX' (Kangchenjunga), previously thought to be the world's highest, is confirmed as 28,156 feet (8,582 meters).