MAHOMET'S DIPLOMATIC ACTION 213 him there that which was judged best for the empire and the citizens. Thereupon the sultan with all haste made terms with Rettirns to. Ibrahim Bey of Caramania and returned to his European ^opiTana capital. When there he at once gave orders that the begins his ■ -tin i i --it active pre- pension to Orchan should no longer be paid, and sent to pactions, arrest all the tax-gatherers in the Strymon Valley who were collecting the money to pay it. He had quieted one possible ally of the empire. He addressed himself next to another opponent who had shown that he could be terribly formidable. He made a truce with John Hunyadi for three years and concluded arrangements with the rulers of other states. He strengthened his army. He amassed stores of arms, arrows, and cannon-balls. He superintended the thorough reform of the administration of the revenue, and in the course of a year he accumulated a third of the taxes which would otherwise have been squandered. Then he determined to carry into execution a plan Purposes which would give him a strong base for operations against f<Si on g the city he was resolved to capture. He was already master Bos P orus - of the Asiatic side of the Bosporus. At what is now Anatoiia-Hissar he possessed the strong fortification built by Bajazed. It is at the place where Darius crossed from Asia into Europe and where the Bosporus is narrowest, being indeed only half a mile broad. Mahomet already possessed by treaty, made with his father, the right to cross the straits and to march through the peninsula behind Constantinople to his capital at Adrianople. He now, however, proposed to build another fortification at some point on the opposite — that is the European — shore. It would serve the double purpose of enabling him to com- mand the straits and of giving him a base for obtaining his supplies from Asia and for the attack by sea upon the city. With a fleet already large at the Dardanelles and with the command of the Bosporus, he hoped to isolate Con- stantinople so far as to prevent it from receiving any aid in men or supplies of food. The command of the Bosporus
