Nuniz states that the successor of Harihara II. greatly improved the city of Vijayanagar, raising fresh walls and towers, increasing its extent, and building further lines of fortification. But his great work was the construction of a huge dam in the Tungabhadra river, and the formation of an aqueduct fifteen miles long from the river into the city. If this be the same channel that to the present day supplies the fields which occupy so much of the site of the old city, it is a most extraordinary work. For several miles this channel is cut out of the solid rock at the base of the hills, and is one of the most remarkable irrigation works to be seen in India. No details are given of the wars he engaged in, except that, besides his campaigns against the Moors, he took "Goa, Chaul, and Dabull," and reduced the Choromandel side of the peninsula to loyalty and obedience to his rule. We learn a great deal more about the doings of Bukka II. and Deva Raya I. from Firishtah than from Nuniz, and I make no apology for quoting copiously from the former author, whose writings throw much light on the period. Bukka's first war began with the invasion already alluded to. It took place during his father Harihara's reign, apparently about the month of December A.D. 1398 (rather later than earlier). The wide cotton plains of that tract are only passable during prolonged dry weather, and the prince would certainly not have risked an advance while there was any likelihood of rain falling. Bukka's son accompanied his father, and the objective was the country of the Doab, and particularly the fortresses of Mudkal and Raichur, then in the hands of the Bahmani Sultan. Sultan Firuz moved to meet him, slaughtering on the way a Hindu chief or zamindar and seven or eight thousand of his followers, "who had always been very troublesome and refractory." The Raya had advanced to the northern frontier of the debatable land and was encamped on the river Krishna, then in full flood, having large bodies of troops posted to oppose the passage of the Muhammadans. "Sultan Feroze Shaw,[84] on his arrival near the river, held a council of war with his chief officers, but received no advice that to him appeared satisfactory. "While the sultan was debating in his own mind how to act, Cauzi Serauje, seeing his concern, offered, if the sultan would permit him, to cross the river with a few of his friends, whom he would select for that purpose, to assassinate Dewal Roy or his son, as he found most convenient....