Spanish, Dutch, French and British Governments in the 16th and the 17th centuries offered huge prize money for anyone who could produce reliable navigational charts. Sailing expeditions in the fifteenth and the sixteenth centuries faced severe impediments because of poor nautical maps. A few Jesuits scholars traveled to India to study the Hindu Panchang system which were known to make use of ready made tables based on local “longitudes” to produce accurate calendars for different parts of the subcontinent. Astronomers in Europe were aided by the information which the Jesuits gathered. Famous astronomer Cassini consulted the famous Siam Table while some others used the Krishnapuram and the Thiruvallur tables which were known equally for their accuracy. Thiruvallur is a town close to Channai, India. An interesting Panchang revolution took place two hundred years later close to Thiruvallur.
|Temple at Thiruvallur|
By the close of the 19th century native Hindu calendar makers, however, had lost touch with an important principle of predicting the position of planets and this delayed the start of the Hindu year by three days. The Panchang calendar were off by 24 minutes in its prediction of the solar eclipse in the year 1878. Ragoonathachary, who hailed from a family of Panchang makers, therefore, proposed a revision to the Panchang tables. He pointed out the fact that the Bija or the “Seed” formulas used in calculating the current position of the planets had not been adjusted for a couple of centuries and that the Panchang makers of the nineteenth century were using outdated formulas. Ragoonathachary, a prudent observer reminded others that astronomers of India such as Aryabhata and Brahmagupta had emphasized the importance of updating Bija formulas based on new observations every couple of centuries.