"دليل بلاد فارس، المجلد I ويشمل محافظات أستراباد، شاهرود-بوستان، خراسان، وسيستان" [و‎‎٨‎٠] (٧٢٢/١٦٤)

DASHT-I-C1 AllMAB— L-vr. , Long. • Elev.
A gently sloping pasture tract in Khurasan, close to Shurab, on the Tehran-
Mashhad road.— (Bellew, Goldsmid.)
DASHT-l-K AV 1 R—Lat. 33° to 36°, Long. 52° to 58°. ; Elev.
The Great Salt Desert that occupies the centre of Khurasan. It com
mences east of Kum, and stretches nearly due east to the boundary
of Turslm, folly 400 miles. Its width varies from 80 to 150
miles. It is composed of dark soil, which has the appearance of having
been turned up by the plough ; but which is covered with a thick salt efflores
cence, which glitters painfully to the eyes. It is absolutely destitute of the
slightest sign of vegetation or of animal life. The surface of the kavir is not
smooth but honey-combed, with small holes about nine inches deep and the
size of a man's head, so as to form very difficult walking for animals; but as
the soil of the kavir binds well, a good road could doubtless be made
over it.
The kavir has every appearance of having been the bed of a shallow sea.
Persians have traditions that it was so ; and though these traditions are
mixed up with fables, still they point to a probable fact. The mountains
bear all the characteristics of strata formed in the bed of a shallow sea or
lake; and their red colour, caused by the presence of oxide of iron, would sup
port this theory.
When the uprising occurred which drained the sea,this desert still remained
considerably below the level of the neighbouring Persian highlands, and
the rivers continued to drain into it and formed marshes. The waters of all
springs and rivers contain salts in minute quantities; but the rivers of Persia
are often so salt as to be undrinkable. The salts brought down by the
rivers are deposited in the marsh, which thus gets salter year by year. It
dries up during the tierce summer heats, to become a marsh again when the
winter floods occur. This process is repeated for ages, and in the course of
time the whole soil over which the marsh extends becomes encrusted with
salt.
When springs are present on a portion of kavir, I have seen the salt extracted
in the following manner. The water is made to pass over a considerable
piece of kavir until it becomes very strongly impregnated with salt; it is
then run down into a shallow basin and allowed to evaporate, leaving a cake
of salt nearly a foot thick. In some places cakes of this thickness are lying
on the surface without any aid from man ; but this is rare. When a com
paratively large river forms the marsh, the extent of country affected is great;
the area" of salt marsh depending upon the volume of water brought
down.
There are various sorts of kavir, depending upon the soil and the amount of
salt. One sort is in ridges looking as if the ground had been ploughed up,
then left fallow for some time, and a glazy coating of salt clay afterwards
poured all over it. When this glazy coating is trodden upon it gives way,
and the horse's hoof sinks into a powdery sort of soil containing much salt.
If this sort of kavir is ridden over, a continued crackling sound is heard,
caused by the horse's feet breaking through the glazy surface. At other
times the whole surface seems rotten, and the horse's feet sink deeply into
it, causing salt to show white on the surface. Sometimes a damp spot is
come upon, looking as if it had sweated up from heiovi.—{MacGregor f
Stewart.)
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