'Handbook of Hejaz' [‎11r] (28/204)

Ridge, one draining the Kheibar harrah, the other the
'Aweiridh harrah, is useful in its upper basin, though
uncultivated in its lower course. One of its feeders
gives Medina its underground waters and extensive subur
ban oasis; the other supplies the palm groves of el-'Ala.-
Other wadis of considerable size debouch near Umlej,
Yambo , Bureika, Rabugh, Jiddah, and Lith, and, in their
middle courses, support a good deal of cultivation and con
siderable hamlets. Most noteworthy m this respect are
Wadis Yambo', Safrah, Fura, Leinuin, and Fatimah.
The valleys of the southern wadis do not affect communi
cations so adversely as in Midian. Many, indeed, facilitate
communication from the coast, e.g. from Umlej to el-'Ala
or Stab) 'Antar, from Yambo' to Medina, from Rabugh to
Medina, and from Rabugh and Jiddah to Mecca.
Hie principal superficial characteristic of FTejaz is general
barrenness, relieved m the first and second zones by rare
oases. 1 he littoral, except near wadi A seasonal or intermittent watercourse, or the valley in which it flows. mouths, is throughout
dusty sand and coralline rock ; the hills of the second zone
are of dusty surface where not harrah or naked rock, and
only at the bottoms of valleys is there rare fertility. The
third zone is stony steppe, softening in the north to sheer
nefud.
2.— C limate.
• ^ needs , therefore, to be stated, that precipitation
is insufficient throughout Hejaz. The Midian highlands get
a little more than the Egyptian Delta ; the rest of Heiaz
more than Middle Egypt, but not much more. Except at
Ta if, in the extreme south, there are no sufficient seasonal*
rams as in Asir and Yemen. On the Ridge and the upper
parts of the seaward slope (including Mecca) precipitation
occurs, both in winter, and occasionally in summer, during
bnef thunderstorms, and water flows down the surface
of Hejaz jiumaras at very rare intervals, though some
times m great volume for a day or two. At Jiddah and in