time of the Blunts' visit in
1879, of not more than 500 houses. The town with its gardens,
surrounded by a mud wall, covers a space of 2 m. in length by half a
mile in width; the basin in which it lies is barely 3 m. across, and
except for the palm gardens and a few patches of corn, it is a dead
flat of white sand, closed in by high sandstone cliffs, beyond which
lies the open desert. The oases of Sakaka and Kara are situated in a
similar basin 15 m. to the east; the former a town of 10,000
inhabitants and somewhat larger than Jauf according to Huber.

The Nafud.

A short distance south of Jauf the character of the desert changes
abruptly from a level black expanse of gravel to the red sands of the
Nafud. The northern edge of this great desert follows very nearly the
line of the thirtieth parallel, along which it extends east and west
for a length of some 400 m.; its breadth from north to south is 200 m.
Though almost waterless, it is in fact better wooded and richer in
pasture than any part of the Hamad; the sand-hills are dotted with
_ghada_, a species of tamarisk, and other bushes, and several grasses
and succulent plants --among them the _adar_, on which sheep are said
to feed for a month without requiring water--are found in abundance in
good seasons. In the spring months, when their camels are in milk, the
Bedouins care nothing for water, and wander far into the Nafud with
their flocks in search of the green pasture which springs up
everywhere after the winter rains. A few wells exist actually in the
Nafud in the district called El Hajra, near its north-eastern border,
and along its southern border, between J. Shammar and Tema, there are
numerous wells and artificial as well as natural reservoirs resorted
to by the nomad tribes.

Owing to the great extent of the Nafud desert, the formation of
sand-dunes is exemplified on a proportionate scale. In many places
longitudinal dunes are found exceeding a day's journey in length, the
valleys between which take three or four hours to cross; but the most
striking feature of the Nafud are the high crescent-shaped sand-hills,
known locally as _falk_ or _falj_, described by Blunt and Huber, who
devoted some time to their investigation. The falks enclose a deep
hollow (known as _ka'r_), the floor of which is often hard soil bare
of sand, and from which the inner slopes of the falk rise as steeply