[58 in finding the moment of his crossing the equinoctial points, while the general precession of the stars remains unaffected by the slight increase assumed in the length of the year. But credit must be given him for his consistency in the view, how over wrong it may be in the light of the facts disclosed. Another important improvement made by Chandrasekhara is in the sun's parallax. The history of his attempts at determin- ing it is no less interesting than the results he actually obtained. The ancient astronomers of India were satisfied with taking for the parallax of exch planet, th part of its mean daily motion, Accordingly, the sun's horizontal parallax was considered to be 3 56", and that of the moon 52 42." With rough instruments at their disposal, the ancient observers could not but assign wrong values. But awkwardly enough, the parallaxes of the sun and moon come into every prediction of their eclipses. - So while modern astronomy increases the distance of the sun to something like 400 times the distance of the moon, our ancient astronomers placed him no 'farther than 14 times this distance. Chandra- sekhara has removed him to a distance of about 154 times the mean distance of the moon. Chandras'ékbara told me that before he got the parallax, he had passed many an unhappy day. He was then very young, "but was anxious to know the sun's distance. He could not even imagine how the distance could ever be known. The'ancient works were dogmatic in their assertions, and did not say a word about the method employed. By his failure in approaching the problem, he became disheartened. One day thus dejected in Digitized by Google
