TYPICAL TASSILI
Wherefore, in many strange ways, it comes back to one, always, that the Sahara is a decadent land. And that is a steadfast impression, that the traveller is always catching, even when least expected.
And, now, to broadly picture the aspect of the country, the Sahara is not, of course, as is often popularly believed, simply a vast track of desert sand. The “floor” of its vast area is made up, principally, of four types of country, which I describe as follows, along with the names by which they are known to the nomads:
| (1)[6] | “Tenere” (Tamascheq[6]) | =Absolute sandydesert.[6] |
| “Arummila” (Arabic) | ||
| (2) | “Adjadi” or “Igidi”(Tamascheq) | =Regions of permanentsand-dunes, sometimes barren, sometimes with scatteredvegetation. |
| “Erg” (Arabic) | ||
| (3) | “Tanezrouft” (Tamascheq) | =Regions where the sand ishard and interspersed with plains of pebbles. Sometimes greatgravel plains as barren as sand desert and hence often calledBlack Desert by the Tuaregs. |
| “Reg” (Arabic) | ||
| (4) | “Tassili” (Tamascheq) | =Regions of chieflyhorizontal, rough, rocky, much crevassed ground, often of shelfrock, where decomposition is very rapid and outcrops much crackedand broken apart. The ground surface, or plateau surface, isusually as barren as sand desert, but in deep ravines in suchcountry there is often a sparse growth of vegetation. |
| “Elkideà” (Arabic) |
As a whole all those regions are practically horizontal, and, except in the north, are on a level well above the sea. Between longitude 5° and 10°, from south to north, the altitudes of the Saharan plains, above sea-level, are approximately:
| Latitude 15° | 1,525 feet (north of Tanout) | ||
| 1,800 feet (Tanout). | |||
| „ 18° | 1,000 feet (desert west of Aïr) | ||
| 1,600 feet (desert east of Aïr) | |||
| 1,220 feet (Bilma Oasis. Longitude 13°) | |||
| „ 20° | 1,500 feet (Gara Tindi) | ||
| 1,350 feet (In-Azaoua) | |||
| „ 22° | 3,100 feet (Zazir) | ⎫ ⎬ ⎭ | Land rising to the AhaggarMountains. |
| 3,700 feet (Tenacurt) | |||
| 4,200 feet (Tamanrasset) | |||
| „ 30° | 350 feet (Hassi Inifel) | Land that falls graduallyaway to a low basin in the El Erg region between the Ahaggar andAtlas Mountains. | |
| 600 feet (Messedli) | |||
The widespread aspect of the Sahara is of vast desolate plains of rock and sand. But a fact which has been overlooked to an astonishing degree, by popular consent, is that the Great Desert is relieved by some very remarkable mountain groups, chief of which are Aïr, Ahaggar, and Tibesti—each in extent as large as the whole of England, and towering majestically to altitudes of 6,000 to 10,000 feet.
They are mountains that are lost to the world; full of mystical silence, like the rest of the Sahara, and bleak and wild, yet they are vast and rich in rugged grandeur; and the greys and browns of their slopes are a feast to the eyes of traveller weary of scanning limitless plains of sand.
A DEEP RAVINE IN THE TASSILI OF AHAGGAR