Sixty generations have passed since the period I describe and what mighty changes have occurred in this interval! The land has extended, rivers have changed their courses, the ancient cities have disappeared and new languages have been formed by sections of the Tamil people. The alluvial deposits which accumulated every year, during the monsoons, at the mouths of the large rivers gradually extended the land as may be seen from the map of India in which the coast line projects into the sea at the mouths of the rivers Godaveri, Kistna, Kaviri, Vaigai, and Tamraparni. In this manner, the backwater that extends from Quilon to Cochin on the Western Coast was formed subsequent to the period of which I treat, as already stated by me in my description of the Ancient Geography of Tamilakam. On the Eastern Coast the land has extended six miles east of the site of Korkai, which was formerly a flourishing seaport. Further north near Guntoor also, the sea coast has receded several miles, and there are traces of the old coast still visible to a length of about 30 miles.
Some of the rivers have changed their courses owing to natural or artificial causes. The Palar which formerly flowed through the bed of the modern Kodu-thalai-âru has quitted its old bed near Tiruvellum, now flows in the south-easterly direction and enters the sea at a place nearly sixty miles south of its former mouth. But the old bed of the river which joins the Kodu-thalaiâru is still known as Palaiya-pâlâru or Vriddha-Kshiranadhi. There is no trace of the river Kaviri, at the site of Kavirip-paddinam, where it was once a broad and navigable river. Many centuries ago, the river breached its banks, after the construction of a dam across it near Tiru-chirap-palli, and formed a new branch now known as Kollidam. The waters of the old Kaviri, east of the dam, are now drawn off by more than a hundred channels to paddy fields stretching over an area of several thousand square miles, and the noble river shrinks to the dimensions of a small channel spanned by a bridge of a single arch before it reaches Mâyâveram, ten miles west of Kavirippaddinam. On the Malabar Coast, the Kotta river which found its way to the sea through Agalap-pula, by the side of the port Thondi, now enters the sea, at a place about eight miles north of the site of Thondi, the channel near which has silted up.
