"نجد الجنوبية: رحلة إلى الخرج والأفلاج والسليل ووادي الدواسر في سنة ١٩١٨." [ظ‎‎٤‎٣] (١٠٠/٩١)

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feet, beside which under the grateful shade of the poplars lolled
idle groups of Arabs eking out the weary hours of the long fast.
Making our midday halt near some unoccupied wells of
this description we pursued our course later in the afternoon
up Shaib Ghuwianam, a small and tortuous tributary of the
Ain, and after a march of nearly two miles to its head climbed
out of it by a steep path to the plateau, here about 2,400 feet
above sea-level. At rather less than two miles further on we
came to a rise in the level of the plateau (about 2,570 feet above
sea-level) from which we commanded a magnificent view right
back to the ridge of Jebel Alaiya on the west and over the ridges
encircling the Kharj valley on the east, while ahead of us beyond
the ridges of the Nisah valley appeared the distant summit of
the Jubeil ridge.
Descending from this eminence for about one and a half
miles we camped for the night in the first of the Balajin depressions
and crossing the remaining two on the following morning finally
passed out of the Alaiya section of Tuwaiq into the broad valley
of Shaib Nisah, which as I have already noted is a great level-
crossing through the barrier of Tuwaiq and brings down the
drainage of part of the plains and hills of Nejd proper. The
valley was here nearly a mile broad and of a sandy character,
running almost due west and east between low lumpy ridges.
Pushing on across the Nisah we ascended the hilly mass
of the ridge on its left bank and soon found ourselves on the
Aridh plateau with a view down on to the Wadi Hanifa and the
ridges behind it ending in Jubeil on the right and a monotonous
expanse of plateau on the left. In front of us at some distance
lay a low black lump, the ridge of Abda, rising abruptly out of
the sloping plateau.
Reaching the Abda ridge after a march of six miles in a
north-west direction from the edge of the Nisah valley we
descended a steep slope, partly rock and partly loose sand,
into the Dahu depression, whose exit into the Wadi Hanifa
lay a short distance to our right. On our left hand the important
Shaib of Baaija, which appears to receive part of the drainage
of the Dhruma plain through the Ausat Shaib, ran down into the
depression along a depressed ridge and re-entered the Tuwaiq
at its further extremity. Striking across the Dahu depression
and entering the Baaija at this point, we marched down the valley
of the latter slightly west of north between high rock cliffs