him to connive at his assassination of the vezīr, Dawlat Bi, under circumstances of peculiar atrocity. Then he gathered all the threads of authority in Bokhārā into his own hands, and, when the dotard Dāniyāl Bi died, in 1770,[470] none of his brethren ventured to dispute his claims to the successorship.[471] He was at first content to govern without reigning; and Abū-l-Ghāzi, the grandson of Abū-l-Fayz, was permitted to retain the trappings of royalty. In 1784, however, Ma´sūm had rendered intrigue and overt opposition to his rule hopeless, and felt strong enough to deprive the forlorn descendant of Chingiz of his shadowy crown. From that year dates the commencement of the reigning house, although the founder eschewed the title of king and adopted that of “Dispenser of Favours.” Ma´sūm, secure at home, turned his eyes to foreign conquest. Khorāsān, the richest province of Persia, was powerless to resist his encroachments; but the road thither was blocked by Bahrām `Alī Khān, a Persian of the Kajar tribe to which the present Shāhs belong. This remarkable man had established himself in the chief strategical position of Central Asia in 1781.[472] He had built for himself a citadel out of the ruins of Old Merv, which, even in its decay, conveys the impression of overwhelming strength; and his stern rule had reduced his kinsmen, the Turkoman tribes, to abject submission.[473] In vain did he attempt to propitiate the ruthless Amīr by an embassy, and offering prayers for the repose of the soul of Dāniyāl Bi. In 1785 Ma´sūm set out for Merv at the head of 6000 Uzbeg horsemen. After lulling Bahrām `Alī into security by one of those ruses in which he was so great an adept, he suddenly appeared before Merv, and drew its defenders into an ambuscade, in which Bahrām `Alī was slain. But the royal city defied his forces, secure in the wealth poured into her lap by a system of irrigation, the work of the Sultan Sanjar of the Seljūk line. Its headworks were a mighty barrage on the Murghāb, thirty miles above Merv, which was guarded by a strong castle.[474] The governor of these defensive works quarrelled desperately with Mahammad Khān,[475] the son and successor of Bahrām Khān; the _causa teterrima belli_ being, as is generally the case, a woman. In the torments of disappointed love he had recourse to the Amīr Ma´sūm, to whom he delivered his charge. Thus Merv’s relentless foe was enabled to strike at the root of its prosperity. He destroyed the Sultan Band, as the barrage was called, and turned the most fertile spot on the world’s surface into a desert. Famine stared the inhabitants in the face, and they had no other resource but to submit to the ruthless Amīr. He obtained possession of the coveted prize without striking a blow, and transported the bulk of its population to Bokhārā, where they have left indelible traces in the population.[476]