Immediately attached to the person of the Assyrian monarch was the Rab-saki, “the chief of the princes,” or vizier. He is called the Rab-shakeh in the Old Testament, by the side of whom stood the Rab-saris, the Assyrian Rab-sa-risi, or “chief of the heads” of departments. They were both civil officers. The army was under the command of the Tartannu, or “Commander-in-Chief,” the Biblical Tartan, who, in the absence of the King, led the troops to battle and conducted a campaign. When Shalmaneser II., for example, became too old to take the field himself, his armies were led by the Tartan Daian-Assur, and under the second Assyrian empire the Tartan appears frequently, sometimes in command of a portion of the forces, while the King is employing the rest elsewhere, sometimes in place of the King, who prefers to remain at home. In earlier days there had been two Tartans, one of whom stood on the right hand side of the King and the other on his left. In order of precedence both of them were regarded as of higher rank than the Rab-shakeh. The army was divided into companies of a thousand, a hundred, fifty, and ten, and we hear of captains of fifty and captains of ten. Under Tiglath-pileser III. and his successors it became an irresistible engine of attack. No pains were spared to make it as effective as possible; its discipline was raised to the highest pitch of perfection, and its arms and accoutrements constantly underwent improvements. As long as a supply of men lasted, no enemy could stand against it, and the great military empire of Nineveh was safe. It contained cavalry as well as foot-soldiers. The cavalry had grown out of a corps of chariot-drivers, which was retained, though shrunken in size and importance, long after the more serviceable horsemen had taken its place. The chariot held a driver and a warrior. When the latter was the King he was accompanied by one or two armed attendants. They all rode standing and carried bows and spears. The chariot itself ran upon two wheels, a pair of horses being harnessed to its pole. Another horse was often attached to it in case of accidents.