FRENCH COLONIAL EXPANSION 143
and Mangin, which had come from Kong to the north-
western part of the Ivory Coast colony by way of Touba.
Thus was established effective connection between the
three protectorates, the Sudan, Guinea. and the Ivory
Coast.
The union of all the French colonial possessions in Africa
was now accomplished; yet four things remained to be done
before this union could be said to be permanent and com-
plete: the complete pacification of the Upper Congo; the
subjugation of Mauretania, making connection between the
Senegal and Algeria possible; the extension of the French
control over the Algerian hinterland and the central Sahara;
and the establishment of proper means of communication
and transport between the various parts of this colonial
empire. The first of these was speedily accomplished, dur-
ing the years 1899-1901, through the capture of Dikoa and
the subjugation of the kingdom of Rabah, by Commandant
Lamy and Captain Dangeville with the combined forces of
the three missions.
Several attempts were made to penetrate the western
Sahara, notably by M. Soleillet in 1880, by Camille Douls
in 1887, and by Fabert between 1889 and 1893; but a suc-
cessful connection of these territories with the other French
protectorates was not accomplished until Paul Blanchet
reached Atar, the capital of Adrar (T-Marr), in 1900. On
June 27, 1900, the Sebkha d’Idjil was added in a delimita-
tion treaty with Spain. In the two years that followed, the
French power was firmly established in the northern portion;
and in 1903 the districts of Trarza and Brakna, just north
of Senegal, were taken over. Finally, the whole region was
formed into the Territory of Mauretania and governed by a
commissioner.
During the years 1859 to 1861, Henri Duveyrier exe-
cuted a series of remarkable explorations covering nearly