THEORY OF THE EARTH. 179 



the whole waters of this river flowed to the south 

 of Ferrara, in the Po de Volano and the Po di Pri~ 

 maro, branches which enclosed the space occupied 

 by the lagune of Commachio. The two branches 

 which were next formed by an irruption of the wa^ 

 ters of the Po to the north of Ferrara, were named 

 the river of Corbolo, Langola, or Maszorno, and the 

 river Toi. The former, and more northern of 

 these, received the Tartaro, or canal bianco, near the 

 sea, and the latter was joined at Ariano by another 

 branch derived from the Po, called the Goro river. 

 The sea-coast was evidently directed from south to 

 north, at the distance of ten or eleven thousand 

 metres* from the meridian of Adria ; and Loreo, to 

 the north of Mesola, was only about 2000 metres^ 

 from the coast. 



Towards the middle of the twelfth century, the 

 flood waters of the Po were retained on their left 

 or northern side by dikes near the small city of Ft- 

 carolo, which is about 19,000 metres^ to the north- 

 west of Ferrara, spreading themselves southwards 

 over the northern part of the territory of Ferrara 

 and the Polesine of Rovigo, and flowed through the 

 two formerly-mentioned canals of Mazzorno and 

 Toi. It seems perfectly ascertained, that this 

 change in the direction of the waters of the Po 



* Equal to 10,936 or 12,030 yards English measure. Transl. 

 f Or 2,186 yards 2 feet English. Transl. 

 I Or 20,778 yards 1 foot 10 inches. Transl. 



