192 JOSEPH THOMSON ON THE GEOLOGY OF [May 1 899, 



between Saffi in the north and Agadir in the south, the apex being 

 the district of Demnat, on the northern slopes of the Atlas Moun- 

 tains, and some 60 miles east of the city of Slorocco. 



Regarded geographically, this area may be described as consisting 

 of three sections : — (1) A comparatively small tract of coastal low- 

 lauds rising to a height of 700 feet, and forming the province of Abda. 

 (2) A larger area of plateau-land occupying the greater portion of 

 the triangle and consisting of two platforms, the northern rising in 

 altitude from 1000 to 2000 feet, forming the provinces of Bled 

 Hummel, Shiedma, Rahamna, and the minor Kaidships into which 

 the plain of Morocco is divided ; while the southern platform 

 consists of more irregular highlands, ranging from 3500 to nearly 

 5000 feet above sea-level, and comprisiug the important provinces 

 of Haha and Mtuga. (3) The third great feature in this part of 

 Southern Morocco is the Atlas itself. Formerly this magnificent 

 range of mountains was described as beginning at the coast, but 

 as the result of my observations I have come to the conclusion that 

 geologically and geographically it commences in reality as a range 

 nearly 30 miles inland, where the glen of the Asif Ig forms a sharp 

 line of demarcation between the plateau and the mountain-chain. 



Assuming, then, that the Atlas range commences at the Asif Ig, 

 we find that it trends east by north, rapidly rising to heights 

 varying between 8000 and 10,000 feet, and forming a massive range 

 which towers up from a broad pediment 2000 to 4000 feet lower. 

 Farther east, or some 60 miles from its western end, the range 

 attains a general altitude of nearly 11,500 feet, the highest summit 

 at this part being Jebel Ogdimt, which I ascended and found to be 

 more than 12,700 feet high. 



Erom Jebel Ogdimt eastward for a distance of 60 miles, the 

 Atlas displays its highest summits, reaching an altitude which 

 I estimated at 14,500 feet, in the culminating mass of the 

 Tizi-n-Tamjurt. At the Tizi Likumpt, on its eastern shoulder, I 

 reached a height of 13,150 feet, and was therefore in a position to 

 form an approximate estimate of the height of the Tizi-n-Tamjurt. 

 Along this central part of the range, the trend of the main axis is north- 

 easterly, a direction which it maintains for a considerable distance. 



Though thus attaining exceptionally high altitudes, the Atlas 

 exhibits scarcely any conspicuous peaks or mountain-masses. Now 

 and again, a part of the range seems to promise such a feature, but 

 in almost every case an alteration of the point of view shows it to 

 be more illusory than real. Seen from the citj^ of Morocco, the 

 only peaks that can be easily identified are Jebel Erduz, Jebel 

 Tezah, Jebel Sig — the Miltsin of Adm. "Washington^ — and Jebel 

 Glauwa; and even these, as compared with the general altitude and 

 imposing mass of the range, are but small protuberances. 



On the whole, the general appearance of the Atlas is disappointing, 



vol. xi (1889), facing p. 64. Views of the mountain and glen scenery, repro- 

 duced from the author's photographs, appear in his popular account of 

 'Travels in the Atlas & Southern Morocco,' London, 1889. — En]. 



^ [' Geographical Notice of the Empire of Marocco,' Journ. Roy. Geogr. See. 

 vol. i (1832) p. 140.] 



