with their twenty-nine gates, opening on the land and sea, and the area they enclose, remain without augmentation or diminution, still unaltered in shape or size, under all the vicissitudes of the city, for fifteen hundred years. When the city had thus increased in magnitude and opulence, it became the great mark for the ambition of the barbarians that surrounded it. Placed at the extremity of Europe, it was the bulwark, as it were, against Asiatic aggression, and, filled with the riches of the earth, the great object of cupidity. In the year 668, after it had stood for three centuries unmolested by strangers, the Saracens attempted to take it. They were at that time a great maritime nation, and had made immense naval preparations. They had been converted to Mohammedanism about forty years, and were under an impression that the sins of all those who formed the first expedition against this Christian town would be forgiven; and they set out with a vast fleet. They disembarked on the shores of the Sea of Marmora, and assaulted the city on the land-side along the whole extent of the wall of Theodosius. The height and solidity of it defied them. For six years they persevered in their attacks, till sickness, famine, and the sword nearly annihilated their vast army. Their attempts were renewed at several times afterwards, and defeated by the terror of the _Greek fire_, which was then for the first time discovered and made use of. The attacks of the Saracens having failed, and the Asiatics having desisted from a hopeless attempt, a new enemy advanced against the devoted city, and from a very different quarter. In the year 865, in the reign of Michael, son of Theophilus, the Sarmatians, Scythians, and the barbarous people now composing the empire of Russia, collected a vast fleet of boats, formed out of the hollowed trunks of single trees, and from hence called by the Greeks _monoxylon_. They descended the great rivers, and, from the mouth of the Borysthenes, fearlessly pushed out into the open sea in those misshapen and unmanageable logs which are still seen in the same regions. Their vast swarms of boats, like squadrons of Indian canoes, arrived at the mouth of the Bosphorus, and darkened the waters of the strait with their countless numbers. But the rude navy of these undisciplined barbarians was either sunk by the Greek fleet, or consumed by the Greek fire. For a century they continued, with unsubdued perseverance, in their fierce attacks, fresh swarms always succeeding to those that were destroyed, till at length one great and final attempt was made to obtain the object of their cupidity.