THE TUAREGS 243 Its source is far away in the north, and it seems to be identical with the Igharghar of the south, alluded to by Duveyrier, the Astapus of the ancients, which comes down from the Atakor or Ahaggar, This would confirm Barth*s suggestion, that the marshy depressions which debouch on the Ngiti Sokoto do not extend beyond the district of Air.

My own opinion is that the Gao Wdy, before it became choked up with sand, was a tributary of the Niger when the course of that river was far more rapid than it is now.

An examination of its banks does in fact lead to the conclusion, that nearly if not quite all along them a line of cliffs, eroded by the action of water, marks what was once the bed of part of the old Niger. In their annual migration the Awellimiden go up as far as the districts near Air, where they come in contact with their enemies the Kel Gheres. Probably competition for the ownership of the pasturages yielding food in the dry season, was the original cause of the feud between the two races, which dates from centuries ago.

The tribes from the left bank of the Niger also move into the kind of islet formed by the bend of the river, advancing to near Dori, where they find a series of ponds and lakes known as Oursi Beli, etc., an idea of which I have tried to give in the map accompanying this volume, but I do not know how far I have succeeded.

There are many very curious and interesting hydrographical problems connected with this bend of the Niger reserved for the future explorer to solve.

Well, what do my readers think of the Tuaregs after the picture I have endeavoured to give of them ? I certainly have not represented them as saints, living in a kind of Utopia, where all is well, where the men have no vices and the women no faults.