ves which were to cheer our eyes for many a long month--many a
long year, maybe. Their dark masses covered the swells right and left,
and near at hand isolated trees formed pleasant patches of shadow.

We left our camping-ground at length next day, having overcome the
obstinate sluggishness of the blacks, and marched nearly nine hours. The
barren forms of the desert begin now to appear, the ground being broken
up into huge hills that run mostly in circles, and groups, and broad
stony valleys. The formation is limestone, often containing flints, with
a little sandstone. Patches of barley here and there splashed this arid
surface with green. At a great distance we saw two or three Arab tents,
and one flock of sheep. Towards evening began to appear a number of
beautiful bushy trees, somewhat resembling our oak in size and
appearance. The Arabs call them "Batoum." They do not seem to have yet
received their proper botanical classification. Desfontaines describes
the tree as the _Pistacia Atlanticis_. It greatly resembles the
_Pistacia lentiscus_ of Linnaeus. A few solitary birds, a flight of
crows, lizards and beetles on the ground; no other signs of life.

The next day the country became more barren still, and the batoum
disappeared. The patches of barley likewise ceased to cheer the eye; and
little pools of water no longer sparkled in the rocky bottoms, as near
Kaleebah. The geological formation was nearly the same as yesterday; but
pieces of crystalline gypsum covered the ground, and the limestone here
and there took the form of alabaster. Some of the hills that close in
the huge basin-like valleys are of considerable elevation, and have
conic volcanic forms. All was dreary, and desolate, and sad, except that
some ground-larks whirled about; lizards and beetles still kept crossing
our path; and a single chameleon did not fade into sand-colour in time
to escape notice. No animals of the chase were seen; but our blacks
picked up the dung of the ostrich, and a horn of the aoudad. Here and
there we observed the broken columns of Roman milestones, some of them
covered with illegible inscriptions. The sockets generally remain
perfect. We saluted the memory of the sublime road-makers.

About noon, as we were traversing these solitudes in our usual irregular
order of march, a crowd of moving things came in sight. It proved to be
a slave-caravan, entirely composed of young girls. The Gadamsee
merchants who owned them recognised