The source of supply was an immense dam erected across the stream thirty-five miles southwards, called Sultān Band, the destruction of which 114 years ago by the Amīr Murād brought utter ruin on the oasis. The mischief wrought by that fanatic has already been, in part, repaired by the Russians; and the charming house of Colonel Kashtalinski, superintendent of the state domains, is embowered in gardens and orchards which will soon restore to this much harassed spot some share of its ancient prosperity. CHAPTER IX BOKHĀRĀ, A PROTECTED NATIVE STATE The 141 miles which separate Merv from the Bokhāran frontier were the costliest and the most depressing section of the Transcaspian Railway. It includes that terror of Russian engineers known as the Sandy Tract,[684] and no trace of cultivation is met with until the weary eye finds solace in the restful green which marks the course of the mighty Oxus. The border stronghold, Charjūy, crowns a hill to the south of the railway line, and bears in its rugged outlines a faint resemblance to Edinburgh Castle. The little town which nestles at its foot is garrisoned by a Russian force consisting of a battalion of Turkestān Rifles and a squadron of Cossacks. At Kerki, 110 miles up stream, three more rifle battalions and a regiment of Cossacks serve as a reminder of the power of Russia. The source of the Amū Daryā is Lake Victoria, a beautiful sheet of water embosomed in the Pamirs 15,600 feet above sea-level, which was visited by Marco Polo, and rediscovered in 1838 by Captain Wood of the Indian Marine.[685] The bed of the great river is 350 yards wide at the point where it leaves the hills at Khwāja Sālih, 90 miles north-west of Balkh; and 200 miles down stream it swells to 650 yards. The mean velocity is 3½ miles an hour, the average depth 9 feet, increasing to a maximum of 29 in August after the annual rains. The course of the Oxus in our day is north-westerly, and it discharges into the Sea of Aral above Khiva. The stream once before bifurcated at Kohna Urganj, 70 miles south of the great inland lake; and one branch flowed south-westwards, entering the Caspian by the Balkhan Bay. At some period in the fifteenth or sixteenth century the Khivans attempted to restrain the course by a dam, and so caused a diversion of the western channel, which can still be traced through the Turkoman Desert.[686] To restore it has been the dream of the Russians since the days of Peter the Great. Elaborate surveys have demonstrated that the operation is perfectly practicable; and those who advocated it urged with truth that the canalisation of the river would turn many thousands of square miles of desert into a garden. The railway has, however, won the day; and the only use made of the Amū Daryā by the Russian authorities is to support a steam flotilla. This service was inaugurated in 1887,[687] and is now carried on by steel-built steamers drawing 2 feet of water, and carrying 200 tons of cargo.