Indian Science and Technology in the Eighteenth Century: Some Contemporary European Accounts c9.38
Indian Science and Technology in the Eighteenth Century: Some Contemporary European Accounts c9.38
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c9.38
23. Let us next compare the places of the sun and moon, for the beginning of the Calyougham, as deduced from the Indian and the modern astronomy. And, first, of the sun, though, for a reason that will immediately appear, it is not to be considered as leading to any thing conclusive. M. Bailly, from a comparison of the tables of Tirvalore with those of Chrisnabouram, has determined the epoch of the former to answer to midnight, between the 17th and 18th³³ of February of the year 3102 before Christ, at which time the sun was just entering the moveable Zodiac, and was therefore in longitude 10ˢ, 6°. M. Bailly also thinks it reasonable to suppose, that this was not the mean place of the sun, as the nature of astronomical tables require, but the true place, differing from the mean, by the equation to the sun's centre at that time.³⁴ This, it must be confessed, is the mark of greatest unskilfulness, that we meet with in the construction of these tables. Supposing it, however, to be the case, the mean place of the sun, at the time of the epoch, comes out 10ˢ, 3°, 38', 13". Now, the mean longitude of the sun, from De La Caille's tables, for the same time, is 10ˢ, 1°, 5', 57", supposing the precession of the equinoxes to have been uniformly at the rate it is now, that is, 50" annually. But M. De La Grange has demonstrated, that the precession was less in former ages than in the present; and his formula gives 1°, 45', 22", to be added, on that account, to the sun's longitude already found, which makes it 10ˢ, 2°, 51', 19", not more than 47' from the radical place in the tables of Tirvalore. This agreement is near enough to afford a strong proof of the reality of the ancient epoch, if it were not for the difficulty that remains about considering the sun's place as the true, rather than the mean; and, for that reason, I am unwilling that any stress should be laid upon this argument. The place of the moon is not liable to the same objection.