The result of the acquisition of Sarukhan, Aïdin, and Menteshe was the immediate appearance of the Osmanlis upon the Aegaean Sea. This is the beginning of the Ottoman naval power, which did not, however, have any development during the reign of Bayezid. The first Ottoman naval expedition started out in the late autumn of 1390. Sixty vessels made a descent upon Chios, and devastated the island. Negropont (Euboea) and the coast of Attica suffered the ravages of the raiders.[450] Bayezid now forbade the exportation of grain from Asia to Lemnos, Lesbos, Chios, and Rhodes. But he was hardly yet in a position to enforce this embargo. The Christians of the Aegaean islands and of the eastern Mediterranean soon learned that a new design, which had before been lacking, animated the Turkish expeditions. It was the desire not so much for booty as for the permanent possession of land. Everywhere they went, the Osmanlis went as settlers. They fought for homes and wives. In the south, Bayezid took Adalia, the last city of the emir of Tekke. It was in 1391 that the Osmanlis won this seaport, their first on the Mediterranean. If we except the southern ports of the Peloponnesus, a whole century passed before they added another on the Mediterranean. Following up the pretext furnished him by a complaint against Alaeddin from his vassal, the emir of Hamid, Bayezid determined to measure his forces against the Karamanlis. As had been the case in the previous similar expeditions under his father, four years before, Bayezid called out the levies of his European Christian vassals. Among those who responded to the call was Manuel Palaeologos, who passed the winter of 1390-91 in the Ottoman camp at Angora. There he wrote his famous dialogues on the Christian religion, purporting to be discussions with a Moslem professor of theology.[451] Bayezid invaded Karamania, and laid siege to Konia. Alaeddin, who had fled to the Taurus Mountains to escape being shut up in the city, saw soon that Konia could hold out against Bayezid for an indefinite period. The Ottoman emir was far from his base of supplies, and nervous about what was happening in Europe. So, when Alaeddin asked for terms of peace, Bayezid agreed to withdraw from Konia, if Alaeddin would formally cede to him the north-western corner of his dominions, including the cities of Aksheïr and Akseraï, which were already in the hands of the Osmanlis.[452] Bayezid left Timurtash as governor of the new acquisitions, and returned to Adrianople. While Bayezid was occupied in Bulgaria, in 1392, in his first defensive campaign against Sigismund, Alaeddin decided upon a supreme effort to wrest from Bayezid the hegemony of Asia Minor. He reoccupied the ceded cities, and attacked by surprise the Ottoman army in Kermian. Timurtash was taken prisoner. One column of the Karamanlis set out for Angora, and the other for Brusa.