ON THE GEOGRAPHY AND GEOLOGY OF THE ATLAS KANOES. 165 



Report of the Committee, consisting of General J. T. Walker, Mr. 

 H. W. Bates {Secretary), General E. Strachey, Mr. W. T. 

 Thiselton-Dyer, and Professor W. Boyd Dawkins, appointed 

 to investigate the Geography and Geology of the Atlas ranges 

 in the Empire of Morocco. 



Report to the Committee. By Joseph Thomson. 



In laying before the General Committee of the British Association a 

 general report on the results achieved by my expedition to the Atlas 

 Mountains, I gladly take the opportunity of cordially thanking the Com- 

 mittee for its substantial and welcome grant of lOOZ. towards the expenses 

 of the work. 



Briefly stated, I left England on March 9, 1888, and returned home 

 in October of the same year, my explorations prematurely, and, as it 

 turned out, quite unnecessarily, cut short by a summons to take command 

 of an expedition for the relief of Bmin Pasha. 



In summarising the results of these seven months' travel in what Sir 

 Joseph Hooker describes as the most difficult of all countries to explore 

 (an opinion in which I heartily agree), it will perhaps be well to consider 

 them under their various heads of Geography, Geology, &c. 



1. Geography. — It is unnecessary to dwell on my travels in the more 

 frequented parts of Morocco. New ground was first touched on my 

 arrival at Demnat among the lower ranges of the Atlas. 



From Demnat I made two excursions across the secondary heights of 

 the great range, on both occasions reaching close to the central crest. By 

 these trips I was enabled to map out the upper course of the Wad Demnat, 

 and partially of the WadTessaout. Among other discoveries of an inter- 

 esting nature in this region, I may refer to the remarkable natural bridge- 

 aqueduct of Iminifiri, which spans a deep narrow gorge, and not only 

 carries a stream of water from one side to the other, but is also used as 

 a bridge by the inhabitants. Noteworthy also were some extensive ancient 

 ruins on the top of Mt. Irghalnsor, and a great series of artificial caves at 

 Tasiraset. 



My next line of exploration lay up the glen of the Wad Gadat from 

 Sidi Rehal. By this glen I penetrated to the very heart of the Atlas, 

 and crossed to the southern side of the mountains by the Tizi-n- Telnet. 

 From the valley of Teluet I made several minor excursions, in one of 

 ■which I ascended Jebel Taurirt (11,168 ft.), the first occasion on which 

 the summit of the Atlas had been reached in this part. 



Proceeding further west, a new attempt was made on the mountain 

 fastnesses from Amsmiz. Following the Wad Amsmiz to its source, the 

 Atlas was again crossed by the pass of Nenieri (9,902 ft.), the head- 

 waters of the Wad Nyfis were explored, and the southern slopes reached 

 by penetrating the canyon of the Wad Agandice. Returning to the 

 Plain of Morocco, the lower mountain course of the Wad Nyfis was traced 

 out, and Amsmiz reached by the Tizi-n-Gerimt (7,215 ft.). 



Further west from Amsmiz the Asif-el-Mel offered a new means of 

 access to the main chain. This glen 1 explored as far aa was practicable, 

 and then, leaving it, crossed by a new pass, the Tizi-n-Nsht (9,715 ft.), to 



