Crawford avalanche. (Grayling, Mich.) 1879-19??, 1892-11-03

Description Of the Worlds Greatest
Desert.

Desert.
The Sahara is an immense zone Of des-
ert which commences on the shores of
the Atlantic Ocean, between the Canaries
and Cape de Verde, and traverses the
whole OF North Africa, Arabia, and Per-
sin, as far as Central Asia. The Mediter-
rancan portion of it may be said roughly
to extend between the 10Th and Both de-
grces of north latitude.
This was popularity supposed to have
been vast inland sea in very recent
timea, but the theory was supported by
geographical facts wrongly. interpreted.
IL has been abundantly proved by. the
researches OF travellers and gcologists
that such a sea was neither the cause nor
the origin of the Libyan Desert.
Rainless and sterile regions of this ma
ture are not peculiar to North Africa,
but occur in two belts which go round
the world in either hemisphere, at about
similar distances north and south of the
equator. These correspond in locality
to the great inland drainage areas from
which no water can be discharged into
the ocean, and which occupy about one
fifth Of the total land surface of the
globe.
The African Sahara is by no means n
uniform plain, but forms several distinct
basins containing considerable extent
of what may almost be called mountain
land. The Hoggar mountains, in the cen
ter OF the Sahara, are 1000 feet high, and
are covered during three months with
snow. The general average may be taken
at 1, 500. The physical character of the
region is very varied. In some places,
such rs Tout, Touat, and other GASES in or
bordering on Morocco, there are well-wat-
cred valleys, with fine scenery and almost
European vegetation, where the fruits
oil the North flourish side by side with
the palm tree. In Others there are rivers
like the Uied CUR, an affluent of the
Niger, which the French soldiers, who
saw it in 1870, compared to the Loire.
Again, as in the bed of the Uied Rir,
there lisa subterranean river which gives
a sufficient supply of water to make
chain of rich and well-peopled GASES equal
in fertility to some of the finest portions
of Algeria. The greater part of Sahara,
however, is hard and undulating, cut up
by dry water courses, such as the Ighar-
CHAR, which descends to the Chott
Mclghigh, and almost entirely without
animal or vegetable life.
About one-sixth of its extent consists
of dunes of moving sand, a vast accumu-
lation of detritus washed down from
more northern and southern regions
perhaps during the glacial epoch-but
with no indication of marine formation.
These are difficult and even dangerous
to traverse, but they are not entirely
destitute of vegetation. Water is found
at rare but well known intervals, and
there is an abundance of salsolaceaus
plants which serve as food for the camel.
This sand is largely produced by wind
action on the underlying rocks, and is
not sterile in itself-it is only the want
of water which makes it so. Wherever
water does exist or artesian wells are
sunk, Gases of great fertility never fail to
follow.
Some parts of the Sahara are below the
level of the sea, and here are formed
what arc called chotts or sebkhas, open
depressions without any outlets, mum
dated by torrents from the southern
slopes of the Atlas in winter and covered
with saline efflorescence in summer.
This salt by no means proves the former
existence of an inland sea. 1t is pro-
duced by the concentration of the natu-
raj salts, which exist in every variety of
soil, washed down by winter rains, with
which the incorporated residue of water
becomes saturated.