It is based upon a triangulation by the U.S. Coast and Geodetic Survey.
He did much to advance stellar photography and its use in cataloguing the stars, and he was responsible for the geodetic surveys of Natal and Cape Colony, British Bechuanaland, German S.-W.
The close of the 19th century witnessed the forging of the final links in the great geodetic triangulation of India, so far as the peninsula is concerned.
Further geodetic connexion with the European systems remains to be accomplished.