VI FLOKTJLA ADEKENSIS. 



falls, while towards its northern extremity it is quite unknown. 

 The few streams that enter from the mountains of Arabia Felix 

 are speedily lost in its arid sands ; cultivation is therefore confined 

 to the vicinity of the few towns and villages, and is dependent on 

 a precarious supply of water from wells. The area of the Aden 

 peninsula is about fifteen miles, its greatest breadth being five 

 miles and its least three. It is connected with the Arabian coast 

 by a narrow sandy isthmus, covered at high spring-tides ; but 

 formerly it was probably an island, since the whole district is of 

 recent origin, being evidently a raised sea-beach ; as is shown by 

 the remains, twenty-three miles inland, of the ancient seaport of 

 Mooza, formerly frequented by the Phoenicians. The peninsula is 

 entirely composed of volcanic rocks of apparently great age, forming 

 numerous precipitous peaks and narrow ridges, which on the 

 southern and eastern sides rise from the sea in inaccessible cliffs, 

 attaining their greatest elevation, 1775 feet, in the peak " Jibeel 

 Shumshum." On the eastern side and towards the isthmus is a 

 considerable depression, the crater of the volcano, surrounded on 

 nearly all sides by high walls of rock and cinder. From the ser- 

 rated ridge Jibeel Shumshum, numerous narrow valleys, shut in by 

 precipices, radiate on all sides towards the sea, in which some end 

 abruptly, while on the northern side others widen out into the 

 limited sea-beach. 



The only patches of vegetation occur at the base of these gorges, 

 just above the sea-line; and the loose and tolerably fertile soil 

 accumulated there consists of scoriae mixed with sand and the de- 

 tritus washed from the rocks above by the violent torrents which 

 rush down every ravine after the rare but heavy falls of rain. 

 Along the cliffs utter sterility reigns, except where a ledge of rock 

 or a mass of cinder has allowed the accumulation of sufficient earth 

 to afford sustenance to a few straggling bushes of Capparis galeata 

 or Adeniwm obesum. 



In so low a latitude the sun shines with intense force nearly 

 throughout the year, and at Aden the solar power is increased by 

 every peculiarity of physical conformation and climate. The un- 

 disturbed atmosphere stagnates in the walled-in valleys, where a 

 death-like stillness always reigns. The black and naked rocks 

 absorb by day the scorching rays transmitted through an ever- 

 cloudless sky, only to radiate the pent-up heat by night, thus con- 

 fining to the shore the cool but feeble breezes that occasionally 

 spring up from the Indian Ocean. Accordingly, even in Decem- 

 ber, when the sun's power is at its lowest, Dr. Hooker found the 



