"نجد الجنوبية: رحلة إلى الخرج والأفلاج والسليل ووادي الدواسر في سنة ١٩١٨." [و‎‎٤‎٢] (١٠٠/٨٨)

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channel of theFara, at the mouth of which we made our midday
halt in a considerable expanse of high sand dunes projecting
out into the plain.
This point was 2,170 feet above sea-level, our course beyond
it running northward along the outer edge of the long slope of
Jebel Alaiya with the storm channel of the Fara parallel to us
on the right at a distance of a quarter of a mile backed by a
long narrow strip of Nafudh between it and the Shaara ridge
beyond. On our right front opened a view of the Khashm Kalb
and Abu Walad ridges with glimpses of the Kharj plain beyond.
Jebel Alaiya comprises a block of the Tuwaiq system,
bounded on the south by the Fara and on the north by the great
level-crossing of Shaib Nisah, the distance between these points
being some sixty miles. It consists of a vast bare plateau
sloping gently down to the east and rising abruptly at the western
end to a high ridge overlooking the western escarpment; the
plateau is scored by the courses of a bewildering number of
ravines, running down independently into the plain, but con
gregating at its western edge in several primary channels to
flow down into the Kharj valley. These channels in order
from south to north are :—
(1) The Fara, whose tributaries are Shaibs Sulaim, Hamlan,
Abu Sahra, Ashairan, and Ashariya,
(2) The Saut, in reality an old branch of the Fara and
separated from it by a small tract of bare rising ground, its
tributaries being Shaibs Quraina (three branches), Abu Farida,
Qahlul, Abu Fuhaid, Umm Nakala, Tarsh, and Wuthailan, the
last an important channel which usurps the place of the Saut
and flows out into the plain round the southern end of Khashm
Kalb, being known indifferently as Wuthailan and Saut; the
tributaries joining this system from north of the Wuthailan
being Shaibs Khamsa (two branches), Umm Salam, Dahla Quad,
Mandasa, Tumair, Mawan, and Ghubaiyid.
(3) The Ain, whose southern tributaries are Shaibs Suwais
(an important channel), Irza, and Sharaimida, while from the
north it is joined by three channels collectively known as the
Balajin (singular Baljan).
The point at which we had halted for our midday rest at
the mouth of the Fara was marked by a small hill or prominence
called Muraiqib, starting from which somewhat late in the