[5] "First modern scientific survey of India" was undertaken by John Mather in 1793–96 on instructions of Superintendent of Salem and Baramahal, Col. Alexander Read.

[6] The Great Trigonometrical Survey (1802–1852) was started by British surveyor Col. William Lambton on 10 April 1802, heading from St. Thomas Mount in Chennai to the foothills of the Himalayas.

[citation needed] 36 inch huge half ton weight Theodolite was used, which took 57 days to measure the 12-km base line.

Pioneering mathematician and Surveyor Radhanath Sikdar measured Mount Everest in 1852, with a height of 29,002 feet.

Appointments to Group 'A' Civil Stream posts in the Junior Time Scale (Dy Supdtg Surveyor) in Survey of India are made on the basis of competitive Indian Engineering Services examination conducted by the Union Public Service Commission .