Indian Science and Technology in the Eighteenth Century: Some Contemporary European Accounts c9.70

c9.70

In seeking for the cause of the secular equations, which modern astronomers have found it necessary to apply to the mean motion of Jupiter and Saturn, M. De La Place has discovered, that there are inequalities belonging to both these planets, arising from their mutual action on one another, which have long periods, one of them no less than 877 years; so that the mean motion must appear different, if it be determined from observations made in different parts of those periods. 'Now, I find,' says he, 'by my theory, that at the Indian epoch of 3102 years before Christ, the apparent and annual mean motion of Saturn was 12°, 13', 14", and the Indian tables make it 12°, 13', 13".