QUESTION When was Mount Everest first measured with any degree of accuracy? How exactly is it measured today?
The Great Trigonometrical Survey of India was a geographical survey of the Indian subcontinent that began in 1802.
Much of the work was done by Sir George Everest, who was the Surveyor General of India until 1843.
He was succeeded by Sir Andrew Waugh, and it was Waugh, who was in post from 1843 to 1861, who surveyed the Himalayas and provided measurements for the Himalayan giants: Everest, K2 and Kangchenjunga.
At the time of the survey, Kangchenjunga was believed to be the highest mountain in the world.
Much of the work was carried out by Sir George Everest, who was the Surveyor General of India until 1843. Pictured: View of Mount Everest
To measure Peak XV, as Everest was then called, Waugh’s surveyors used triangulation.
Observers surveyed the peak from several points at known distances; they were then able to measure the angle from Everest’s summit to their observation points.
It took years to calculate the results, and when they found it to be exactly 29,000 feet (8,839.2 m), Waugh publicly stated in 1856 that Everest was 29,002 feet, to avoid the impression that it was an approximation.
As one log later put it, Waugh was the first person ‘to set two feet on the summit of Mount Everest’.
The mountain was measured several times over the next century, with about 27 feet added to the height.
To measure Peak XV, as Everest was then called, Waugh’s surveyors used triangulation. In the picture: Trekkers on their way to Everest base camp
In the latest calculations, Chinese and Nepalese scientists used the Global Navigation Satellite Systems (GNSS) to produce about 300 control points that were used to collect trigonometric data.
On May 22, 2019, an expedition team carried a GNSS receiver and antenna to the summit of Everest to obtain satellite data.
Everest’s height is now officially 29,031.69 feet or 8,848.86 m.
However, the exact height of any great mountain is disputed due to variations in snow level, among other factors.
JS Lewis, Oxford.
QUESTION Did Isaac Newton borrow his famous phrase ‘standing on the shoulders of giants’?
Issac Newton noted in a letter to his rival Robert Hooke, dated 5 February 1675: ‘What Des-Cartes (sic) did was a good step.
‘You have added much in several ways, and especially in taking the colors of thin plates into philosophical consideration.
“If I have seen further, it is by standing on the shoulders of giants.”
By this time Hooke and Newton were on good terms – they were later to become enemies – and it appears that Newton complimented Hooke.
Pictured: Sir Isaac Newton, an English mathematician and physicist
Newton was alluding to a simile used much earlier by Bernard of Chartres, a 12th-century philosopher.
His contemporary, John of Salisbury, wrote in his 1159 Metalogicon that Bernard would say that “we (the moderns) are like dwarfs sitting on the shoulders of giants (the ancients), and thus we are able to see more and longer than the latter.’
L. Weston, Solihull, W. Mids.
QUESTION Was the Sabbath observed during the battles of the American Civil War?
To the early settler, strict observance of the Lord’s Day was a sacred and necessary part of the religious life.
In the 19th century, America’s success led to increased commerce and leisure that put pressure on Sabbath observance.
Organizations such as the Philadelphia Sabbath Association and the influential New York Sabbath Committee arose to combat this.
The Civil War (1861-65) between the states further eroded the social fabric of the nation.
The demand for Sunday work was increased by the urgency of the war, Sunday transport of troops and supplies became part of the war effort, and the desire for news from the front led to an expansion of the Sunday postal service.
The New York Sabbath Committee caused President Lincoln to issue the General Order Respecting the Observance of the Sabbath in 1862, in which: ‘The President, Commander-in-Chief of the Army and Navy, desires and enjoins the orderly observance of the Sabbath. of officers and men in military and naval service.
The New York Sabbath Committee prompted President Lincoln (pictured) to issue the General Order Respecting Sabbath Observance in 1862
‘The importance to man and beast of the prescribed weekly rest, the sacred rights of Christian soldiers and sailors, a growing respect for the best feelings of a Christian people… demand that the Sunday work in the army and navy be reduced to that end. of strict necessity.’
Under the stress of war, however, these commands proved impossible to comply with. In the South, the exigencies of war pained General Lee.
He wrote to his daughter in December 1861: ‘One of the miseries of war is that there is no Sabbath, and the present work and strife have no cessation.’
T. McPherson, Daventry, Northants.