Indian Science and Technology in the Eighteenth Century: Some Contemporary European Accounts c9.36

c9.36

22. The Brahmins place the beginning of their moveable Zodiac, at the time of their epoch, 54° before the vernal equinox, or in the longitude of 10s, 6°, according to our method of reckoning. Now, M. Le Gentil brought with him a delineation of the Indian Zodiac, from which the places of the stars in it may be ascertained with tolerable exactness.³⁰ In particular, it appears, that Aldebaran, or the first star of Taurus, is placed in the last degree of the fourth constellation, or 53°, 20', distant from the beginning or the Zodiac. Aldebaran was therefore 40' before the point of the vernal equinox, according to the Indian astronomy, in the year 3102 before Christ. But the same star, by the best modern observations, was, in the year 1750, in longitude, 2s, 6°, 17', 47"; and had it gone forward, according to the present rate of the precession of the equinoxes, 50" annually, it must have been, at the era of the Calyougham, 1°, 32', before the equinox. But this result is to be corrected, in consequence of the inequality in the precession, discovered by M. De La Grange,³¹ by the addition of 1°, 45', 22", to the longitude of Aldebaran, which gives the longitude of that star 13' from the vernal equinox, at the time of the Calyougham, agreeing, within 53', with the determination of the Indian astronomy.³²