"العراق والخليج الفارسي" [ظ‎‎٩‎٢] (٨٦٢/١٨٩)

Il6 GEOLOGY AND DESCRIPTION OF THE LAND
the Nafud. East of Lina it begins to curve south-eastwards and
continues with a breadth averaging 15 miles, but sometimes much less,
for a distance of 100 miles, roughly parallel to the Ardh al Madhu but
converging with it eastwards. It reaches and crosses the Wadi Batin,
smothering the depression with sand. Thereafter it sweeps round in
a great curve, at first parallel to the shore of the Persian Gulf and 200
miles distant from it, and then bends round to the south-south-west
till it joins the Ruba al Khali, ‘the empty quarter’ of southern Arabia.
It has a total length of 700 miles.
Between the Nafud and the Wadi Batin the sands of the Dahana
are neither deep nor difficult to cross; occasionally they are scarcely
noticeable as a land feature; elsewhere the dunes, alined from east to
west, are 50 feet high and 300 yards apart from crest to crest. In the
Nafud, where the sand is deeper, horseshoe-shaped hollows (falj)
have been scooped out of the sand, with depths of 150-200 feet.
They vary in size from an acre to more than 100 acres, but all lie with
the deepest part of the horseshoe towards the north-west, the direc
tion of the prevailing wind. Travel is very slow and laborious in the
Nafud because of these hollows, the accompanying dunes, and the
soft texture of the sand.
In the rainy season these sand-deserts support a surprising amount
of vegetation: there are large bushes of ghadha which serve as fuel,
and tall succulent grasses which are so nourishing in spring that
camel-herds become independent of water for weeks at a time.
Thus at this season the nomads wander far into these sandy tracts,
finding abundant fuel and pasture, and living on the milk of their
camels. Moreover, though there are practically no wells within the
dune areas, the margins of the belts are fairly well supplied with water.
The Wadi Batin
From Zubair, 10 miles south-west of Basra, the ground rises gently
to the crest of the desert steppe known as Ar Raha, north of Kuwait
territory, to the west of which is the mouth of the Wadi Batin, marked
by two bluffs, Ar Ratak ash Shamali and Ar Ratak al Janubi. There
is excellent grazing in Ar Raha during March. Where the Wadi Batin
forms the boundary between Iraq and Kuwait (p. 2) it has steeply
sloping banks, with a width of from 1 to 4 miles between crests on
either side. The banks are cut by numerous small dry tributaries
(shaib). A clayey loam covers the bottom of the depression and affords
a fertile soil for grass and bushes.
This depression, which in its lower course is known as the Wadi