The main purpose for establishing it was to assist in navigation and mapping by recording the latitude and maintaining time standards.

Sir Charles Oakley accepted Petrie's plea to establish an official observatory for the purpose of "promoting the knowledge of astronomy, geography and navigation in India".

At the centre a granite pillar of 10 tons supported a 30-centimetre (12 in) azimuth transit circle instrument made by Troughton.

Goldingham returned in 1812 and served until 1830 when he was replaced by Thomas Glanville Taylor who measured the positions of 11,000 stars which were published in five volumes which came to be known as the "Madras Catalogue".

Tennant was in charge of the observatory and magnetic observations began to be made using vertical force and declination magnetometers.

Pogson was succeeded after his death by C. Michie Smith who moved to Kodaikanal to study solar physics in 1899 was replaced by R.L.