An excursion into Afghanistan—The salt deposits of God-i-Zirreh—Sand hills—Curious formation of hill range—Barchans and how they are formed—Alexander's march through the country—The water of Godar-i-Chah—Afghans and their looks.
The excursion which I made into Afghan territory to the salt deposit of Gaud- or God-i-Zirreh, and a lower depression to the east of it, was of great interest to me.
There are a great many theories regarding these former salt lakes, and it is not easy to say which is right and which is wrong. The general belief is that these lakes were formed by the overflow of the Halmund swamp into the Shela (river) which carried sufficient water not only to fill up the God-i-Zirreh, but to overflow when this was full into the next depression east of the Zirreh.
There is no doubt that to a great extent this was the case, but these lakes were, I think, also fed more directly by several small streams descending from the mountains to the south and west of the Zirreh, which form the watershed—and very probably also from the north by the Halmund River itself. Both lakes were dry and seemed to have been so for some time. The God-i-Zirreh, forming now a great expanse of solid salt some 26 miles long by 5 or 6 wide, extends in a long oval from west to east. The other lake was somewhat smaller.
To the south of these salt deposits in the zones between them and the present Afghan boundary, and forming the southern fringe of the Afghan desert, the soil is covered with gravel and stones washed down from the mountain sides. Very stony indeed is the desert towards the Malek-Siah end, then further north-east appear brown earth, shale, and sand. To the north of the lakes was a long line of bright yellow sand extending from west to east and broad enough towards the north to reach the bank of the river Halmund. Another shiny patch, which at first, from a distance, I had mistaken for another smaller lake, turned out on examination to be a stretch of polished shale which shone in the sun, and appeared like bluish water.
Stunted tamarisk grows in some parts but not in the immediate neighbourhood of the salt deposits. We have here instead a belt of myriads of small conical sand-hills, also spreading from west to east, quite low to the west and getting higher for several miles towards the east. In the south-west part of the desert, curiously enough, between the zone of conical hills and the salt deposits, and parallel to both, lies a row of semi-spherical sand and salt mounds of a whitish colour.
To the east-south-east of the lakes the sand-hills rise to a great height and eventually form a high ridge, which for some reason or other is cut perpendicularly on its western side, possibly as the result of a volcanic commotion. Of similar origin probably was the gigantic crack caused by an earthquake which we shall examine later on near Nushki. In fact, both the crack at Nushki and the collapse of the west side of this hill range, as well as a great portion of that deep crack in the earth's crest in which the Shela flows, have very likely been formed by the same cause. They are within the same zone of volcanic formation. In the particular case of this hill range in Afghanistan the collapse did not appear to me to be due to the action of water, but to a sudden crumbling which had caused a very sharp vertical cut.
Sand Hills.
To the north of the salt wastes was another long belt of yellow sand extending for some 40 miles, upon which there was absolutely no vegetation, while intervening between the salt and this sand flat were numerous sand barchans, like horseshoes, with a gradual slope on the windward side (north) and a crescent hollow with a steep but not quite vertical bank on the lee side.