Hell Is Above Us: The Epic Race to the Top of Fumu, the World's Tallest Mountain Jonathan Bloom (free children's online books .TXT) đź“–
![](/uploads/posts/books/3/2/2/3/4/kniga-hell-is-above-us-the-epic-race-to-the-top-of-fumu-the-world's-tallest-mountain.jpg)
- Author: Jonathan Bloom
Book online «Hell Is Above Us: The Epic Race to the Top of Fumu, the World's Tallest Mountain Jonathan Bloom (free children's online books .TXT) 📖». Author Jonathan Bloom
Measuring Fumu has been a source of much tension ever since the first summit attempt was made in 1881. At that time, it was given short shrift for a variety of reasons and assumed to be almost one thousand feet shorter than Everest. It was not until Hoover’s fateful summit attempt of 1939 that people started learning what many had already felt might be true – that Fumu was the tallest mountain in the world. But before the Hoover expedition, people did what they often do: Rely on the word of experts who may or may not know what they are talking about in order to understand their world.
The experts in this case were geodesists, people who study the size and shape of the Earth. Fumu was first measured by geodesists who cared little about its height. They were in the middle of much larger projects at the time and the measurement of the Himalaya was of secondary importance.
William Lambton of Yorkshire had been in India since the turn of the 19th Century, trying to figure out nothing less than the shape of the Earth. Other geodesists had recently completed measurements in the Arctic Circle and at one point on the equator. They had surmised the Earth was an “oblate spheroid.” In other words, the world is not round as many had assumed, but rather shaped like a grapefruit; flattened at the poles and sticking out further at the equator. Lambton wished to supplement these findings by continuing the measurements in a small region of India called Mysore.
The British liked the idea of measuring India. It was, after all, their spoils, and it would be nice to know the size of the prize. The Raj could only be strengthened by this knowledge. Therefore, Lambton was pushed to measure more than just Mysore. Soon he had minions reporting to him and the Great Trigonometric Survey of India had begun.
Lambton’s plan was to survey a straight line up the sub-continent along the Great Indian Arc of the Meridian and another line across the sub-continent from Mangalore to Madras. The north-south line along the Great Arc would ultimately end up covering 1,600 miles from Cape Comorin in the south to Mussoorie in the north, and would take about 47 years and untold lives to complete. Off of the Great Trigonometric Survey would sprout countless secondary series by other surveyors, until almost all of India and modern-day Pakistan were shackled under a chain of triangles.
At its core, the survey method used by Lambton was just very basic trigonometry. Hold three flags up in different locations, creating a triangle (These were big triangles. Many were several miles along the hypotenuse). Measure the distance between any two of the three flags - A and B - using something like a chain, giving you length of side AB. This is your baseline. From A and B, get a site line of the third flag - C - and calculate the angles of those site lines from the baseline. You can then use that data to calculate the length of AC and BC, and the angle of the third corner C. Viola. The whole triangle of land has been measured! Now you can start a new triangle using one of the sides of the triangle you just measured.
Of course, that description only describes measurements on a horizontal plane, like a map. But heights of locations needed to be recorded as well. This also required basic trigonometry, but with the added challenge that one of the corners of the triangle was inevitably hidden under the earth because no ground is perfectly flat. Start by planting a flag at sea level – corner A. Go to some nearby high point and plant another flag – corner B, again connected by a chain. Calculate the angle from straight vertical at the high point B and the angle from straight horizontal at the low point A. This gives you the other two sides of the right triangle, and thus the height of the second point. As one moves up from sea level to mountainous ranges, one just keeps adding and adding elevations, triangle by triangle.
Based on the description just given, the reader may be led to think a trigonometric survey of India was technically simple but repetitive, as if the surveyors were machines, running basic calculations over and over again. But nothing could be further from the truth. Lambton, and later George Everest after Lambton’s death, faced untold challenges while measuring the sub-continent and it was these challenges that would ultimately lead to the faulty measurement of Fumu.
First there are the challenges inherent to trigonometric surveying. Take even the basic notion of measuring altitude from “sea level.” Do you start your measurement at the high tide mark, the low tide mark, or an average of the two? How do you ensure other surveyors running secondary series are doing it the same way?
There is also the issue of the Earth being an “oblate spheroid.” When calculating the vertical triangles, you must take into account the curvature of earth. Even if the effect is tiny for a single triangle, less than an inch perhaps, the error will be compounded as you tack on more triangles, Altitude measurements will soon be out of whack. So if the world is not a perfect sphere, what formula can you use reliably?
When you look over an expansive vista at mountains or other large objects in the distance, what you are seeing is actually bent by water in the atmosphere, much like looking at a fish in a fish bowl. This phenomenon is called refraction. Surveyors trying to get a site line on distant objects are not immune to refraction,
Comments (0)