PHYSIOGRAPHY OF EASTERN PERSIA. 
229 
Evidences of the strength of the wind and the paucity of rain abound every- 
where. In many parts of the Hehnund delta the fierce "Wind of One Hundred 
and Twenty Days " has scooped in the smooth plain great hollows 6 or 8 feet deep, 
20 or 30 feet wide, and hundreds of feet long. Universally the long axis is directed 
to tlie north-northwest. At first sight these hollows appear to have been formed by 
running water, but the testimony of the natives, the location of the depressions 
where no water could come, the uniform orientation, and the known force and 
direction of the wind iniite to make it certain that they are of teolian origin. In 
this same region a peculiar effect was called to my notice by Mr. G. P. Tate, 
topographer of the Sistan Arbitration Commission. Sistan abounds in ruins made 
of sun-dried brick. Wherever the old walls stand in a north-and-south direction, 
parallel to the prevailing course of the wind, they remain standing indefinitely, 
Fig. 151. — Ruins at the Mil-i-Kasimabad, near Zahidan. These mud wails are at least five hundred years old. 
Only those in a north-and-south direction remain standing. 
although gradually worn ver}- thin by attrition. Wherever the walls stand in the 
other direction, and are exposed to the full power of the wind, they are speedily 
blown away and disappear entirely. Thus it happens that tlie ruins often present 
the appearance shown in the illustration (fig. 151), where numerous north-and-south 
walls stand intact, with almost no east-and-west walls to connect them. Besides 
these more unusual results, the wind plays its well-known part in beveling pebbles 
and bricks and in etching out and carrying away the softer parts of the rocks. 
In winter the winds, although prevailingly from the northwest, are less severe 
and less regular than in summer. Occasional cyclonic storms are accompanied by 
southeast winds (St. John, p. 7), which bring the scant rainfall of the couutr\-. At 
its best the rainfall is sufficient to tinge the mountains with green for a few weeks 
in spring and to support a scanty population of villagers and nomads ; at its worst, 
it supports nothing but a few prickly bushes, and famine destroys unnumbered 
people and animals. The curse of Persia is the aridity due to the continental 
position of the country and to its rim of high mountains. 
