HELMUND, a river of Afghanistan, in length about 600 m. The Helmund, which is identical with the ancient Etymander, is the most important river in Afghanistan, next to the Kabul river, which it exceeds both in volume and length. It rises in the recesses of the Koh-i-Baba to the west of Kabul, its infant stream parting the Unai pass from the Irak, the two chief passes on the well-known road from Kabul to Bamian. For 50 m. from its source its course is ascertained, but beyond that point for the next 50 no European has followed it. About the parallel of 33° N. it enters the Zamindawar province which lies to the N.W. of Kandahar, and thenceforward it is a well-mapped river to its termination in the lake of Seistan. Till about 40 m. above Girishk the character of the Helmund is that of a mountain river, flowing through valleys which in summer are the resort of pastoral tribes. On leaving the hills it enters on a flat country, and extends over a gravelly bed. Here also it begins to be used in irrigation. At Girishk it is crossed by the principal route from Herat to Kandahar. Forty-five miles below Girishk the Helmund receives its greatest tributary, the Arghandab, from the high Ghilzai country beyond Kandahar, and becomes a very considerable river, with a width of 300 or 400 yds. and an occasional depth of 9 to 12 ft. Even in the dry season it is never without a plentiful supply of water. The course of the river is more or less south-west from its source till in Seistan it crosses meridian 62°, when it turns nearly north, and so flows for 70 or 80 m. till it falls into the Seistan hamuns, or swamps, by various mouths. In this latter part of its course it forms the boundary between Afghan and Persian Seistan, and owing to constant changes in its bed and the swampy nature of its borders it has been a fertile source of frontier squabbles. Persian Seistan was once highly cultivated by means of a great system of canal irrigation; but for centuries, since the country was devastated by Timur, it has been a barren, treeless waste of flat alluvial plain. In years of exceptional flood the Seistan lakes spread southwards into an overflow channel called the Shelag which, running parallel to the northern course of the Helmund in the opposite direction, finally loses its waters in the Gaod-i-Zirreh swamp, which thus becomes the final bourne of the river. Throughout its course from its confluence with the Arghandab to the ford of Chahar Burjak, where it bends northward, the Helmund valley is a narrow green belt of fertility sunk in the midst of a wide alluvial desert, with many thriving villages interspersed amongst the remains of ancient cities, relics of Kaiani rule. The recent political mission to Seistan under Sir Henry McMahon (1904–1905) added much information respecting the ancient and modern channels of the lower Helmund, proving that river to have been constantly shifting its bed over a vast area, changing the level of the country by silt deposits, and in conjunction with the terrific action of Seistan winds actually altering its configuration. (T. H. H.*)