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Did Radhanath Sikdar Measure the Height of Mount Everest First?

Did Radhanath Sikdar Measure the Height of Mount Everest First?

View northward of Mt. Everest from an aircraft. The aircraft is south of the mountains. Everest is above the ridge connecting Nuptse and Lhotse. 2012. Photo: shrimpo1967/Wikimedia Commons, CC BY-SA 2.0


  • The Great Trigonometrical Survey commenced its ‘North-Eastern Himalayan Series’ in 1845 and completed it in 1850.
  • Andrew Waugh, the surveyor-general in 1843-1863, ordered that the identification of peaks must be left to the computers – and Radhanath Sikdar was the chief computer.
  • But in 1849, he along with his computing office was moved to Calcutta – and as soon as he retired, in 1862, the office was brought back to Dehradun.

Who calculated the height of the highest peak of the world, and so discovered Mount Everest?

In India, many have believed that Radhanath Sikdar was the discoverer of Mount Everest. Banglapedia, the national encyclopaedia of Bangladesh, blandly states that “while in service, he discovered the highest peak of the Himalayas, and also the highest peak in the world”.

Wikipedia’s version is more colourful. According to it, Sikdar started measuring the height of mountains at the order of Col. Waugh, George Everest’s successor as the surveyor-general. He calculated the height of this ‘Peak XV’ to be exactly 29,000 ft, but Waugh added an arbitrary two feet because he was afraid that Sikdar’s figure would be considered a rounded number instead of an accurate one.

The Great Trigonometrical Survey (GTS) was an extremely well documented enterprise, both scientifically and administratively. A perusal of published records clearly establishes that Sikdar had no role in the calculation of the heights of the Himalayan peaks. However, he was the chief computer, the head of the mathematics department, so why was he not involved? Thereby hangs a tale.

On December 20, 1831, Sikdar had been a student at the Hindu College Calcutta for seven years when he was given an appointment in the newly established computing office. George Everest was immediately struck by his mathematical abilities and took him under his wings. Everest took him to Mussoorie/Dehradun, where he would remain for the next 15 years.

A photo of Radhanath Sikdar, before 1870. Photo: Wikimedia Commons, public domain

His regular job began in 1832 as a sub-assistant. His salary was Rs 107 per month, comprising a pay of Rs 50, tent allowance of Rs 40 and horse allowance of Rs 17. In 1838, when his monthly salary was Rs 173, Sikdar expressed a wish to leave GTS for a profitable post as ‘teacher to a public institution’. Everest made a strong plea to the government to grant Sikdar a substantial increase as an inducement to stay. Everest said that Sikdar had been “trained from boyhood under my own eye” and that his mathematical attainments “would rank very high … even in Europe”.

Sikdar was, Everest continued, “the cheapest instrument that Government ever could employ in a task of this kind”. Accordingly, Sikdar was given a special increase of Rs 100 from June 1, 1838. And in 1845, he was made the chief computer.

Himalayan peaks

The GTS commenced its ‘North-Eastern Himalayan Series’ in 1845 and completed it in 1850. It spanned 2,720 km from Dehradun to Sonakhoda, in Purnia, Bihar. The mightiest of the Himalayan peaks are visible from the principal stations of this series. Everest’s successor, Andrew Waugh, the surveyor-general from 1843 to 1863, ordered that every visible peak, great and small, should be observed from every observing station, but that the identification of peaks must be left to the computers.

Under normal circumstances, Sikdar’s mathematics department would have carried out the computations. But in 1849, he along with his computing office was moved to Calcutta.1 And as soon as he retired, in 1862, the office was brought back to Dehradun. It is in this period that the heights of various Himalayan peaks were calculated. One can’t help but conclude that Sikdar’s banishment from the theatre of activity was driven by racism and ‘superioritism’.

Immediately after Sikdar vacated Dehradun, a “small office” was established there  under the superintendence of J.B.N. Hennessey, a first assistant in the GTS. It was “composed of native Surveyors, and newly joined Sub-Assistants, who thus had an opportunity of being rigorously trained in the theoretical portion of their new duties”.2

George Everest. Photo: Maull & Polyblank/Wikimedia Commons, public domain

The “computations of the snow peaks, including Mount Everest,” were made at this office, under Hennessey. True to form, none of the native sub-assistants associated with the computations was ever named.

Surveyors observed ‘Peak XV’ – later dubbed Mount Everest – from six distinct stations between November 27, 1849, and January 17, 1850. Its height was independently calculated for each of the observations. The numbers in all cases were mutually consistent, ranging from 28990 ft to 29026 ft and yielded a mean value of 29,002 ft.3 A Karakoram peak, known then as well as now as K2 – with a height of 28,250 ft – turned out to be the second-highest. The next three highest were Kanchenjunga I (28,146 ft), Kangchenjunga II (27,803 ft), Dhaulagiri (26,795 ft). In 1865, the  Royal Geographical Society named Peak XV after Everest, on Waugh’s suggestion. This is the only peak that was named.

Mount Everest returned to the news 50 years later. In 1904, GTS superintendent Sidney Gerald Burrard wrote in passing in the scientific journal Nature, “About 1852 the chief computer [Radhanath Sikdar] of the office at Calcutta informed Sir Andrew that a peak designated XV had been found to be higher than any other hitherto measured in the world”.4

This statement cannot be true, because Waugh was in Dehradun and Sikdar in Calcutta. This appears to be a case of inversion. It is on record that while Hennessey’s office was making calculations, the surveyor-general made “constant reference to the Chief Computer regarding special formulae and adjustments that had to be allowed … to provide for such great distances”.5

If anything, it would have been Waugh telling Radhanath about developments in Hennessey’s office, instead of the other way around.

A quarter of a century later, in 1928, a surveyor named Maj. Kenneth Mason (1887-1976), who later became the University of Oxford’s first geography professor, delivered a speech at Shimla, entitled ‘Himalayan Romances’. He is said to have declared that “it was during the computations of the north-eastern observations that a babu rushed on one morning in 1852 into the room of Sir Andrew Waugh” and exclaimed, “Sir, I have discovered the highest mountain on the earth”.

The invention of Radhanath Sikdar as the ‘discoverer of Mount Everest’ as the highest in the world began in 1933, with Jogesh Chandra Bagal quoting Mason in a paper published in The Modern Review.6 According to Bagal, a report on the speech was published in The Englishman on November 12, 1928. But in the absence of access to the complete report, it is difficult to assess this isolated quote. It would be instructive to see the whole report.

As things stand, this solitary, unsubstantiated statement has been repeated variously with or without embellishment.

Had Sikdar’s office been retained at Dehradun, he would have had the privilege of presiding over a department that carried out the computation of the height of Mount Everest and other peaks. His removal from the scene just before action began was deliberate, and with a view to denying him – a high-profile ‘native’ – a legitimate place in history.

Rajesh Kochhar is a former professor of astrophysics and former director, National Institute of Science, Technology and Development Studies, New Delhi, and the author of The Vedic People: Their History and Geography (2000).


  1. Phillimore, R.H. (1963-4) Indian Archives, Vol. 15, pp. 33-4.

  2. Progress of Trigonometrical Survey, 1861-2. Journal of Asiatic Society of Bengal, 1864, Vol. 32, p. 122.

  3. Ref. 2, p. 43.

  4. Burrard, S. G. (1904) Mount Everest: The story of a long controversy. Nature, 71 (November 10), p.43. https://www.nature.com/articles/071042a0.pdf

  5. Ref. 1, p. 35.

  6. Bagal, J.C. (1933), Radhanath Sikdar: The great mathematician and discoverer of Mount Everest. Modern Review, 53 (4), 457-460.

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