charged with a mission in the Soudan.

This vast region is situated between the fifteenth and
tenth degrees of north latitude; that is to say, that, in
order to approach it, the explorer must penetrate fifteen
hundred miles into the interior of Africa.

Until then, the country in question had been known
only through the journeys of Denham, of Clapperton, and
of Oudney, made from 1822 to 1824. Richardson, Barth,
and Overweg, jealously anxious to push their investigations
farther, arrived at Tunis and Tripoli, like their predecessors,
and got as far as Mourzouk, the capital of Fezzan.

They then abandoned the perpendicular line, and made
a sharp turn westward toward Ghat, guided, with difficulty,
by the Touaregs. After a thousand scenes of pillage, of
vexation, and attacks by armed forces, their caravan
arrived, in October, at the vast oasis of Asben. Dr. Barth
separated from his companions, made an excursion to the
town of Aghades, and rejoined the expedition, which
resumed its march on the 12th of December. At length it
reached the province of Damerghou; there the three travellers
parted, and Barth took the road to Kano, where he
arrived by dint of perseverance, and after paying
considerable tribute.

In spite of an intense fever, he quitted that place on
the 7th of March, accompanied by a single servant. The
principal aim of his journey was to reconnoitre Lake Tchad,