Passage: The Great Trigonometrical Survey was a project which aimed to measure the entire Indian subcontinent with scientific precision. It was begun in 1802 by the infantry officer William Lambton, under the auspices of the East India Company. Under the leadership of his successor, George Everest, the project was made a responsibility of the Survey of India. Everest was succeeded by Andrew Scott Waugh and after 1861 the project was led by James Walker, who saw the first completion of it in 1871.

Question: What was the purpose of the Great Trigonometrical Survey?
measure the entire Indian subcontinent