Wednesday, April 30, 2008

The Great Arc

I read very few books these days, but I am glad that The Great Arc was one among the few. It is wonderful book written by John Keay, an Englishman, about one of the greatest scientific feats of the 19th century. Before you start thinking about mile-long bridges or sky-high buildings, hey... There are things in life that people rarely know about and the science(and art) of Surveying is one of them.



I am in fact gifted to have learned this subject as part of my curriculum, though I wonder how many of my classmates share my opinion. People have often asked me what Surveying is. I am no expert in it and therefore my explanation does not make any impact on them. I say,"It involves getting the measurements from ground about the features there and transferring it to a map." People say,"Oh great. Is that all? You study only that for a year at college?" The point is I would recommend to these people the book I just mentioned.

The book is about a series of measurements made by two Englishmen, William Lambton and George Everest, of the entire Indian subcontinent spanning a period of fifty years. They made what are called triangulations across the entire subcontinent in times when there were no lights, no telegraph, no telephone, etc. It was no simple feat. For example, the beginning of the series of triangulations, called the Great Indian Arc of the Meridian, was at St.Thomas Mount in Chennai. A baseline of 12 Km was measured for some 50 days. The presicion with which these measurements were made was phenomenal. In a distance of about 1 m, the error would not exceed 1 mm. (In today's measurement the tolerances are 1 um in 1 m !!!). This was a stupendous task for times when no modern equipment like GPS were available. The author of the book goes so far to say that the amount of computations performed by the surveyors back then would take several days to complete in a supercomputer today.

The measurements were made in the field for years together in places where tigers roamed free and malaria wrecked havoc. There are more things I would like to mention but might end up writing an entire book!

The second name is probably familiar to many, George Everest. You guessed it, Mt.Everest is named after him, but not because he measured its height but because of the services he rendered by looking after the Great Arc for 30 years. This comes to show the respect these two commanded for their feats. Had it not been for the Great Arc we would never have had maps of India and we would never have known the heights of the Himalayas.

I read the book twice, once in my III semester and once in my IV. I found that it complemented my Survey course. I understood it better when I read it for the second time, since I knew a lot about the instruments like theodolites, levels, chains, etc.

The Great Arc was also publicised as a documentary in NDTV's Documentary 24x7. But it did not go beyond what I read in that book. I hope that I have made a little effort in bringing some light to this mammoth event that took place 200 years ago.

Links

Survey of India's Celebration

Surveying

P.S.: I took the photograph of the book myself. One of my many efforts in photography.

6 comments:

geodexter said...

Amazing! I have a strange satified feeling after reading this post. Dude, you indeed have a hand at writing! Congrats.

Buddy, include me in your list of die hard surveying fans. True, I too share the same opinion of yours.

George Everest!! long time ago (guess I was in the first to second year holidays) i read about everest\'s adventures and endeavour in surveying the great India. He was a promising student of the Orient Survey school in the Great Britain and surveying the Indian terrain was such a challenge that could be given only to enterprising surveyors. Everest was their immediate choice. It was featured as an article in Current Science magazine.

Well, the Great Arc is my next book :)

By the way, have you read \"The Longitude\" ? by Dava Sobel? Check that one too, it would leave you spellbound. I became such a fan of Sobel that I went all way to purchase the rest of all the books she had written. (Yet to read them though)

Srinath S said...

Thank you if you think I have a hand at writing. But I must tell you that, unlike your blog that deals with all issues ranging from societal problems to the latest in technology(often in an artistic style), mine is more focussed on what I do everyday and what interests me.

Cool! Then Longitude is undoubtedly my next book. Haven't read it yet.

I must also point the fact that it seems more often that Everest takes all the credit for the Great Arc. This is not the case. William Lambton was actually the one behind this mammoth achievement and truly deserves as much, if not more, credit as Everest. But it is sad to note that his(Lambton's) grave somewhere in MP is now being used as a public convenience.

geodexter said...

OH is it? Lambton.. i faintly remember this name. Oh, it sad to note that some people hardly come to limelight.

Nitin said...

well...where to start...yeah,now i remember..
a year ago u took a seminar on this very book...Flawless!Brilliant!
I must admit that you inspired me to a great deal.
After hearing from you, analogous to "Anyone can cook" in Ratatouille, i felt "Anyone Can WIN"!!!!!!keep posting your wonderful,out-of-the-world thoughts.

Srinath S said...

Thanks Tintin!

Aziza said...

Well said.