fNTRODUCTION xxxi different branches (pp. 1-7). The Golapada which deals. with the celestial sphere and spherical astronomy is also prefixed with 2. special introductory section (pp. 118-22). Suryadeva's explanations are generally elucidative and his statements are sometimes backed by the citations of earlier authorities. The mathematics set out in the Ganita-pada is generally illustrated by worked out examples and the computations of planets set out in the Golapada with directions for practical demonstrations. 2. Notable points 1. Date of Aryabhata While divergent views have been held as to whether the Kali year 3600 mentioned in ABh, iii. 10 refers to the date of Aryabhata's birth or to the date of the composition of Aryabhaṭīya,” Sūryadeva categorically agrees with the latter view. Thus he gives the meaning of ABh, iii. 10 as follows: “When 600 solar years have elapsed in Kali, which is the fourth part of the current (maha-)yuga, this treatise (Aryabhatiya) has been composed by me who am 23 years old.” (p. 93). Explaining the purpose of the mention of the date of the work as above by Aryabhata, Suryadeva adds: “What is the purpose of this statement ? I shall explain. At this point of time, the mean positions of the planets, and their apogees and nodes, as computed using their revolution-numbers given in the Gitika-pada, would be exact (and, so, do not stand in need of any correction). At that point of time, the Sun's northward and southward transits, respectively, occurred exactly at the commencement of Capricorn and Cancer, (the precession of the equinoxes being zero).” (com. on iii. 10, p. 93). Corrections in computations could, therefore, be counted from this date. 2. Dasagitika and Aryastasata-Two works While the Gitika-pada, on the one hand, and the Ganita, Kalakriya and Gola-padas, on the other, together make up the Aryabhatiya, Suryadeva points out that essentially, the two are independent works. Posing a question, "Then, how is this discipline constituted of two Vir 1. For the details of these views, see Pt. I, pp. 95-98.
