SYR-DARYA RIVER (Gr. and Lat. Jaxartes; Arab. Shash or Sihun), a river of Asia, flowing into the Sea of Aral, and having a length of 1500 m. and a drainage area of about 320,000 sq. m. Its headstream is the Naryn, which rises in the heart of the Tianshan complex south of Lake Issyk-kul, on the southern slope (12,000 ft.) of the Terskei Ala-tau. After its union with another mountain stream, the Barskaun, it flows W.S.W. at 1 1, 060 to 10,000 ft. above the sea, in a barren longitudinal valley between the Terskei Ala-tau and the foothills of the Kokshal-tau. On entering a wild narrow gorge in the southwest continuation of the Terskei Ala-tau it receives the name of Naryn. Within this gorge it descends some 4000 ft.; Fort Narynsk, 20 m. below the confluence of the Great and the Little Naryn, is only 6800 ft. above the sea. Here the river enters a broad valley formerly the bottom of an alpine lake and flows past the ruins of Fort Kurtka, for 90 m. westward, as a stream some 50 yds. wide and from 3 to n ft. deep. Its waters are utilized by the Kirghiz for irrigating their cornfields, which contrast strangely with the barren aspect of the lofty treeless mountains. The At-bash, a large mountain stream, joins the Naryn at the head of this valley and the Alabuga or Arpa at its lower end, both from the left. Before reaching the lowlands the Naryn cuts its way through three ridges which separate the valley of Kurtka from that of Ferghana, and does so by a series of wild gorges and open valleys (170 m.), representing the bottoms of old lakes; the valleys of the Toguztorau, 2000 ft. lower than Kurtka, and the Ketmen-tube are both cultivated by the Kirghiz. Taking a wide sweep towards the north, the river enters Ferghana also the bottom of an immense lake where, after receiving the Kara-darya (Black River) near Namangan, it assumes the name of Syr-darya. 1 The Kara-darya is a large stream rising on the northern spurs of the Alai Mountains. As it deflects the Naryn towards the west, the natives look upon it as the chief branch of the Syrdarya, but its volume is much smaller. At the confluence the Syr is 1440 ft. above sea-level.
The waters of the Syr-darya and its tributaries are in this part of its course largely drained away for irrigation. It is to the Syr that Ferghana is indebted for its high, if somewhat exaggerated, repute in Central Asia as a rich garden and granary; cities like Khokand, Marghilan and Namangan, and more than 800,000 inhabitants of the former khanate of Khokand, subsist by its waters. Notwithstanding this drain upon it, the Syr could be easily navigated, were it not for the Bigoyat rapids at Irjar, at the lower end of the valley, where the river pierces the Mogol-tau.
On issuing from this gorge the Syr enters the Aral depression, and flows for 850 m. in a north-westerly and northerly direction before reaching the Sea of Aral. On this section.it is navigated by steamers. Between the Irjar rapids and Baildyr-turgai (where it bends north) the river flows along the base of the subsidiary ranges which flank the Chotkal Mountains on the north-west, and receives from the longitudinal valleys of these alpine tracts a series of tributaries (the Angren, the Chirchik, the Keles), which in their lower courses fertilize the wide plains of loess on the right bank of the Syr.
Some 50 m. below Chinaz (770 ft. above sea-level) the Syr bends northwards, but resumes its north-westerly course 150 m. farther down, following with remarkable persistency the edge of the loess. Its low banks, overgrown with reeds and rendered uninhabitable in summer by clouds of mosquitoes, are inundated for 20 m. on both sides when the snows begin to melt. These inundations prevent the moving sands of the Kyzyl-kum desert from approaching the Syr; below Perovsk, however, the steppe does gain the upper hand. Down to Perovsk the river rolls its muddy yellow waters, at the rate of 3 to 5 m. an hour, in a channel 300 to 600 yds. wide and 3 to 5 fathoms deep; at Perovsk its vertical section is 8220 sq. ft., and 312,500 cub. ft. of water are discharged per second. The Arys and the Bugun are the only tributaries worthy of notice along this part of its course; the other streams which descend from the Kara-tau fail to reach the river. The Kirghiz rear numerous herds of cattle and sheep in the valley of the Arys, while lower down, as far as Julek, the Iginchis carry on agriculture. All this applies of course only to the right bank ; on the left the moisture is absorbed by the hot winds which cross the Kyzyl-kum sands towards the river. The dryness of the atmosphere has a marked effect upon the Syr when it gets below Julek, the Kara-kum sands being then on its right. Ten miles below Perovsk the river traverses a marshy depression (the bottom of a lake not yet fully dried up), where it divides into two branches the Jaman-darya and the Kara-uzyak. The latter spreads out into marshes and ponds, from which it again issues to join the former at Karamakchi, after a course of 80 m. The main arm, owing to its shallowness and sinuosity, is very difficult to navigate, and the difficulty is increased by the rapidity of the current and the want of fuel. Between Kazalinsk and the Sea of Aral (158 ft.) navigation becomes somewhat easier, except for the last 10 m., where the river divides into three shallow branches before entering the " Blue Sea." All three have at their mouths sandy bars with only 3 ft. of water.
1 Syr and darya both signify " river," in two different dialects.
Two former right-hand tributaries of the Syr the Chu and the Sary-su now disappear in the sands some 60 m. before reaching it. The Chu, which is 600 m. in length, rises in the Tian-shan south-west of Lake Issyk-kul, and as the Kashkar flows towards Lake Issyk-kul, but a few miles before reaching that lake turns suddenly to the northwest, enters under the name of Chu the narrow gorge of Buam, and, piercing the snow clad Kunghei Ala-tau, emerges on its northern slope, having descended from 5500 ft. to less than 2000 in a distance of not more than 50 m. In this part of its course it receives from the right the Kebin, whose high valley equals in size that of the upper Rhone. It then flows north-westwards through the valley of Pishpek, and, avoiding the Muyun-kum sands, describes a wide curve to the north before finally taking a western direction. Numberless streams flow towards it from the snow-clad Alexander Mountains, but they are for the most part lost in the sands before reaching it. The Talas, 170 m. long, formerly an affluent of the Chu, which rises in the highest parts of that range, pierces the Cha-archa Mountains, and, flowing past Aulie-ata on the south border of the Muyun-kum, enters the salt lake of Kara-kul 60 m. from the Chu. The Chu terminates in the Saumal-kul group of lakes, 60 m. from the Syr. Another elongated group of lakes the Uzun-kul near the above, receives the Sary-su, which has a length of nearly 570 m. and flows rapidly in a narrow channel along the western edge of the northern Famine Steppe (Bekpak-dala).
The delta of the Syr begins at Perovsk, whence it sends a branch to the south-west, the Jany-darya (New River), which formerly reached the south-eastern corner of the Sea of Aral, very near to the mouth of the Amu-darya. The Kirghiz affirm that a canal dug for irrigation by the Kara-kalpaks gave origin to this river. It had, however, but a temporary existence. A dam erected by the people of Khokand at Ak-mechet (Perovsk) caused its disappearance, and the Russians found nothing but a dry bed in 1820. When the dam was removed the Jany-darya again reappeared, but it failed to reach the Sea of Aral; in 1853 it terminated in Lake Kuchka-denghiz, after a course of 250 m. ; all traces of its bed were then lost in the sand. Five centuries ago, in the time of Timur, the Mongol prince of Samarkand, the Jany-darya brought the waters of the Syr to the Daukara lakes, close by the present mouth of the Amu. The series of old river-beds in the Kyzyl-kum, which are still seen above Perovsk, indicates that the Syr had a constant tendency to seek a channel to the south-west, and that its present delta is but a vestige of what it was once. At a still more remote period this delta probabjy comprised all the space between the Kara-tau and the Nura-tau in Samarkand ; and the series of elongated lakes at the base of the Nuratau the Tuz-kaneh and Bogdan-ata lakes represent an old branch of the delta of the Syr which probably joined the Zarafshan before reaching the Amu. The cause of this immense change is simply the rapid desiccation of all the northern and central parts of Asia, due to the fact that we are now living in the later phase of the Lacustrine period, which has followed the Glacial period. The extension of the Caspian Sea as far as the Sary-kamysh lakes during the post-Pliocene period and the extension of the Sea of Aral at least 100 m. to the east of its present position are both proved by the existence of post-Pliocene marine deposits. (P. A. K. ; J. T. BE.)
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)