Geodetic survey is actually a vast area survey process. The line joining any two points is considered as a curved line. The triangle formed by any three points is considered to be spherical and the angle of the triangle is assumed to be spherical angles. Geodetic survey is conducted by the Survey Of India department, and is carried out over an large area exceeding 250 KM2.
The first geodetic survey of note was observed in France during the latter part of the 17th and early 18th centuries and immediately created a major controversy. JEAN PICARD began an arc of triangulation near Paris in 1669-70 and continued the work southward until his death about 1683. His work was resumed by the Cassini family in 1700 and completed to the Pyrenees on the Spanish border prior to 1718 when the northern extension to Dunkirk on the English Channel was undertaken.
The survey created a major controversy. For the results indicated that the earth was a prolate ellipsoid, which contradicted Issac Newton's 1687 postulate that it was an oblate figure. To resolve the hue and cry that followed, the French Academy of Sciences in Paris proposed in 1733 that the length of the meridian be measured near the equator and compared with that obtained in France. Later it was decided to do the same in the Arctic region. The Torne River valley north of Tornio in Lapland on the Swedish-Finnish border was chosen as the northern site and observations were begun in 1736 and completed two years later.
The results showed conclusively that one degree of the meridian was longer in Lapland than at Paris and proved Newton's postulate to be correct. The expedition to Peru, the present day Ecuador departed in 1735 and returned nine years later with results that confirmed the Lapland finding, i.e. one degree of the meridian is shorter at the equator than in France.
The first geodetic survey of note was observed in France during the latter part of the 17th and early 18th centuries and immediately created a major controversy. JEAN PICARD began an arc of triangulation near Paris in 1669-70 and continued the work southward until his death about 1683. His work was resumed by the Cassini family in 1700 and completed to the Pyrenees on the Spanish border prior to 1718 when the northern extension to Dunkirk on the English Channel was undertaken.
The survey created a major controversy. For the results indicated that the earth was a prolate ellipsoid, which contradicted Issac Newton's 1687 postulate that it was an oblate figure. To resolve the hue and cry that followed, the French Academy of Sciences in Paris proposed in 1733 that the length of the meridian be measured near the equator and compared with that obtained in France. Later it was decided to do the same in the Arctic region. The Torne River valley north of Tornio in Lapland on the Swedish-Finnish border was chosen as the northern site and observations were begun in 1736 and completed two years later.
The results showed conclusively that one degree of the meridian was longer in Lapland than at Paris and proved Newton's postulate to be correct. The expedition to Peru, the present day Ecuador departed in 1735 and returned nine years later with results that confirmed the Lapland finding, i.e. one degree of the meridian is shorter at the equator than in France.
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