Mount Everest, the Reconnaissance, 1921. George Mallory

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СКАЧАТЬ in repose is inclined about 35̎ to this plane, at Kurseong about 51̎, at Siliguri about 23̎, at Dehra Dun and Mussooree about 37̎. For this reason all angles of elevation to Himalayan peaks measured from the plains, as Mount Everest was measured, are too small and consequently all our values of Himalayan heights are too small. Errors of this nature range from 40 to 100 feet.”

      This then is a considerable source of error, but the most serious source of uncertainty affecting the value of heights is the refraction of the atmosphere. A ray of light from a peak to an observer's eye does not travel along a straight line but assumes a curved path concave to the earth. The ray enters the observer's eye in a direction tangential to the curve at that point, and this is the direction in which the observer sees the peak. It makes the peak appear too high. Corrections have therefore to be applied. But there is no certainty as to what should be the amount of the correction; and it is now believed that the computers of the height of Mount Everest applied too great a correction for refraction and consequently reduced its height too much.

      Burrard brings together in the following table the different errors to which the carefully determined height of Mount Everest is liable:—

Source of error.	Magnitude of possible error.
Variation of snow level from the mean	Unknown
Errors of observation	10 feet
Adoption of erroneous height for observing station	10 feet
Deviation of gravity	60 feet, too small
Atmospheric refraction	150 feet, too small

      The following table shows how the different values of the height of Mount Everest have been deduced:—

      Height of Mount Everest

Observing station.	Year of observation.	Distance in miles.	Height as determined by Waugh.	Determination of height with revised correction for refraction.
			Feet	Feet
Jirol	1849	118	28,991	29,141
Mirzapur	1849	108	29,005	29,135
Joafpati	1849	108	29,001	29,117
Ladnia	1849	108	28,998	29,144
Harpur	1849	111	29,026	29,146
Minai	1850	113	28,990	29,160
Suberkum	1881	87	—	29,141
Suberkum	1883	87	—	29,127
Tiger Hill	1880	107	—	29,140
Sandakphu	1883	89	—	29,142
Phallut	1902	85	—	29,151
Senchal	1902	108	—	29,134
Mean	—	—	29,002	29,141

      The height 29,141 is still, Burrard thinks, too small, as it has yet to be corrected for the deviations of gravity. But though it is a more reliable result than 29,002, the latter is still to be retained in maps and publications of the Survey of India.

      As to the name, it was called Everest after the distinguished Surveyor-General of India under whose direction the triangulation had been carried out, one result of which was the discovery of the mountain. From the Indian side and Nepal it is not a conspicuous peak on account of its lying so far back. No native name for it could be discovered and Sir Andrew Waugh, the successor of Sir George Everest, called it after his predecessor. From the Tibetan side it is much more conspicuous and, as General Bruce stated in his lecture to the Royal Geographical Society in November 1920, and as Colonel Howard-Bury found in 1921, the Tibetans call it Chomolungma, which Colonel Howard-Bury translated, the “Goddess Mother of the Mountains”—a most appropriate name. But the name Mount Everest is now so firmly established throughout the world that it would be impossible to change it. It is therefore now definitely adopted.

      Now, this mountain so coveted by mountaineers is unfortunately situated exactly on the border between two of the most secluded countries in the world—Nepal and Tibet. To reach it the climbers must pass through one or other of these countries and the difficulty of getting the necessary permission is what has so far prevented any attempt being made to attack Mount Everest. But recently access through Tibet has become more possible, and it so happens that it is on the Tibetan side that the summit seems most accessible. From the distant views that could be obtained of it from Sandakphu beyond Darjeeling and from Kampa Dzong in Tibet, a ridge running from the summit in a northerly direction seemed to give good promise of access. Major Ryder and Captain Rawling in 1904, viewing the mountain from a distance of sixty miles almost due north, thought the mountain might be approached from that direction. At the same time the Tibetans were distinctly more favourable to travellers than they had ever been before. The chances therefore of at least exploring Mount Everest were much more promising, and Major Rawling was planning an expedition of exploration when the war broke out and he was killed.

      Mr. Douglas Freshfield would certainly have taken the matter up during his Presidency of the Royal Geographical Society, but he had the misfortune to hold that post during the years of the war and no action was possible. But as СКАЧАТЬ