Great Trigonometrical Survey
Also called: GTS, Great Arc · Topic: Maps and Map Scale · NCERT: Beyond NCERT
Meaning
The Great Trigonometrical Survey (GTS) was a long project to measure India exactly. It was begun in 1802 at Madras by William Lambton. It used triangulation, which means fixing the position of points with chains of triangles. It ran along a long north–south line called the Great Arc. George Everest carried it on and was Surveyor General from 1830 to 1843. The GTS gave India accurate maps and helped give the country a fixed territorial shape.
Example
Using GTS data, the Indian mathematician Radhanath Sikdar worked out around 1852 that Peak XV in the Himalayas was the highest peak. It was named Mount Everest in 1865.
Don't confuse with
- Survey of India: the Survey of India is the mapping department, set up in 1767. The GTS was one major survey that it carried out from 1802.