202 THE EMPTY QUARTER

the chief advantage accruing from our prolonged sojourn at
<Ain Sala was the opportunity afforded for an useful series
of star and sun observations for the determination of its
Latitude and possibly also of its Longitude.

Next morning at 9 a.m. we broke camp and started off for
Naifa, the baggage pursuing the direct route while I, accom-
panied by Ibn Ma'addi and Farraj, made a slight diversion
more to the south to inspect two exposures of rock, which
they had noted the previous day while out in search of game.
Such patches of rock in the midst of the desert sands were as
interesting to me as uncharted islands in unknown seas are
to the wandering mariner, and I always found the Arab ready
to examine any spot where the presence of water might be
suspected.

After half an hour we came to the first exposure—a patch
of rock in a hollow of the sands which seemed to be an
incipient horseshoe. Here again we found a number of fox
earths and the sand was strewn with fulgurites. Only a well
mouth was wanted to complete the picture but we found it
not. So we christened the spot Al Sailan with reference to
its nearness to 'Ain Sala and passed on until, after about 20
minutes' marching, we came upon a regular hillock about
30 feet high situated in the pit of a typical horseshoe cavity
of the low, adjoining sandridge. There were other lesser
exposures of rock strata in the sand-slopes around, while
fox earths were numerous both in the flanks of the eminence
and on its summit. We again however drew blank for the
suspected well and contented ourselves with adding a new
name to the local map—calling the place Al Manifa, at
Farraj's suggestion, by reason of its comparatively great
elevation.

A few moments later we passed from Hadh <Ain Sala into
Khilla Naifa, a tract of some half dozen rather bare dune
ranges of the now usual NE.-SW. orientation, which are
separately grouped under the name of Bani Riman on
account of the strikish whiteness of their colouring in con-
trast with the brown or ruddy hue of the sands we had left
behind. Tracks of bustard, hare and fox were seen abun-
dantly, but we had little time to waste in search of game as