Indian timekeeping

Ghatis and water bowls

Traditional Indian timekeeping divided the day into 60 ghatis; sinking-bowl water clocks (ghati yantra) measured them in temples and courts.

Jantar Mantar

Between 1724 and 1734 Sawai Jai Singh II built masonry observatories at Delhi, Jaipur, Ujjain, Varanasi and Mathura. The Samrat Yantra at Jaipur, a giant equinoctial sundial, reads local time to about two seconds; the Jaipur observatory is a UNESCO World Heritage Site.

Clocks at court

Mughal and princely courts collected European clocks; the Salar Jung Museum in Hyderabad preserves a famous English musical clock among many others.

Astronomy and the measurement of time

Indian astronomical texts divided the day into 60 ghatis of 24 minutes, each ghati into 60 palas and each pala into 60 vipalas. The sinking-bowl water clock — a copper bowl with a small hole that fills and sinks in a set time — is described in the Surya Siddhanta tradition and was used in temples and courts into the 19th century. Astrolabes made in Lahore and other Mughal centres from the 16th century, often by families of instrument makers, carry Persian and sometimes Sanskrit inscriptions.

Court clocks and standard time

Mughal emperors received European clocks from embassies, and princely states built up large collections; the musical clock by Cooke and Kelvey of London in the Salar Jung Museum, Hyderabad, in which a small figure strikes the hours, draws crowds every hour. Railways and the telegraph spread standard time: Indian Standard Time, 5 hours 30 minutes ahead of Greenwich, was adopted in 1906, although Calcutta and Bombay kept their own local time for decades.

Timeline

1. 1724–1734Sawai Jai Singh II builds monumental observatories, including the Samrat Yantra sundial at Jaipur — Sawai Jai Singh II