
How the Great Trigonometric Survey led to the mapping of India
Chennai, then Madras, 1819. Syed Mir Mohsin Husain, a jeweller from Arcot, was working in the store of his employer, George Gordon, when some British military officials stopped by with a strange instrument, asking if Mohsin could fix it. Though he had never seen such an instrument before, he managed to repair it, a skill…