ADEN PENINSULA. 5 



of tlie original volcano which appear to have been since removed. The 

 western flanks forming the outer slope of the volcano, and which must 

 originally have had a much more gentle inclination, are deeply cut into by 

 valleys and ravines, and a huge mass of matter has been denuded away. 

 The section cuts obliquely across the flank here, so that it does not 

 illustrate this point fully. Along the southern part of the edge there 

 are almost vertical precipices of many hundred feet, on the outside as 

 well as on the inside of the crater, and thus the line of hill is reduced to 

 a mere narrow ridge ; h-d is a plateau deeply scored by ravines, ending in 

 one ease in a fine precipice, over which the water pours in a torrent after 

 a heavy fall of rain ; 6 is a small hill (500 yards north-west of the Tawella 

 tanks) as nearly as possible in the centre of the great crater, and contain- 

 ing itself a crater-like hollow, the wall of which is broken through on 

 the east side. This hill at once suggests to one's mind the inner crater 

 so common in volcanoes, and such I believe it to be. A large breach has 

 been opened in the eastern side of the great crater at Front Bay : 

 the wall has been entirely removed and also no doubt the eastern 

 portion of the plateau h-d, which was originally merely the solidified 

 floor of the crater after the last eruptions. 



From the walls of the crater several long spurs are thrown ofi' radi- 

 ally. Of such Marshag is one and Seerah island apparently another; a 

 third runs northward towards the isthmus, and several smaller ones are 

 traceable along the southern shore. The most important one, however, 

 is that which runs westward for 2^ miles from Shumshum to 

 Steamer-point, sending out an oflTshoot northward to the little pass ; and 

 which forms the backbone of all the western part of the Peninsula. 

 It seemed to me possible that the hills from the little pass south- 

 ward and eastward to Shumshum, might be the remains of another 

 crater and not merely a denuded spur from the cantonment crater. 

 The strata (if one may use the expression with reference to volcanic 

 rocks) appear, as seen in a bird^'s eye view from Shumshum, (see Plate A.) 



( 261 ) 



