and the inscription of the Dinar, though it might be censured by some timorous casuists, proclaimed the unity of the God of Mahomet. Under the reign of the caliph Walid, the Greek language and characters were excluded from the accounts of the public revenue. If this change was productive of the invention or familiar use of our present numerals, the Arabic or Indian ciphers, as they are commonly styled, a regulation of office has promoted the most important discoveries of arithmetic, algebra, and the mathematical sciences. Whilst the caliph Walid sat idle on the throne of Damascus, whilst his lieutenants achieved the conquest of Transoxiana and Spain, a third army of Saracens overspread the provinces of Asia Minor, and approached the borders of the Byzantine capital. But the attempt and disgrace of the second siege was reserved for his brother Soliman, whose ambition appears to have been quickened by a more active and martial spirit. In the revolutions of the Greek empire, after the tyrant Justinian had been punished and avenged, an humble secretary, Anastasius or Artemius, was promoted by chance or merit to the vacant purple. He was alarmed by the sound of war; and his ambassador returned from Damascus with the tremendous news, that the Saracens were preparing an armament by sea and land, such as would transcend the experience of the past, or the belief of the present age. The precautions of Anastasius were not unworthy of his station, or of the impending danger. He issued a peremptory mandate, that all persons who were not provided with the means of subsistence for a three years' siege should evacuate the city: the public granaries and arsenals were abundantly replenished; the walls were restored and strengthened; and the engines for casting stones, or darts, or fire, were stationed along the ramparts, or in the brigantines of war, of which an additional number was hastily constructed. To prevent is safer, as well as more honorable, than to repel, an attack; and a design was meditated, above the usual spirit of the Greeks, of burning the naval stores of the enemy, the cypress timber that had been hewn in Mount Libanus, and was piled along the sea-shore of Phnicia, for the service of the Egyptian fleet. This generous enterprise was defeated by the cowardice or treachery of the troops, who, in the new language of the empire, were styled of the _Obsequian Theme_. They murdered their chief, deserted their standard in the Isle of Rhodes, dispersed themselves over the adjacent continent, and deserved pardon or reward by investing with the purple a simple officer of the revenue. The name of Theodosius might recommend him to the senate and people; but, after some months, he sunk into a cloister, and resigned, to the firmer hand of Leo the Isaurian, the urgent defence of the capital and empire. The most formidable of the Saracens, Moslemah, the brother of the caliph, was advancing at the head