32 Dr W. Hibberfs Rtmarks on the 



which has taken place may be seen. I ascertained that hot 

 springs similar to this, but which I had not an opportunity of 

 visiting, existed also at a place several miles to the eastward, 

 and also at Muscat, which is about 1^ days' journey inland. 

 As is usually the case, I think there can be little doubt as to 

 the existence, and that not very far distant, of some internal fire, 

 a circumstance which is in a measure supported by the know- 

 ledge we possess of other parts of the coast,* as well as from 



" The circumstances alluded to above refer to the known existence of a 

 recently extinct volcano, and also volcanic remains in the small islands and 

 coral rocks, so numerous and notoriously dangerous on the Arabian side of 

 the Red Sea. 



The most interestingof these, from the circumstance of its having been seen 

 burning so late as 1 8.33 and 1 834, as well as being the largest, is the island called 

 Jebel Teir or Tor. At the time we saw it some smoke was visible, occasioned 

 by sulphureous exhalations similar to those daily occurring at Vesuvius, and 

 some of the neighbouring phenomena, as Solfatara, &c. It is composed of an- 

 cient as well as modern volcanic rocks, in some parts, having a stratified ap- 

 pearance, as if of layers of tufa and lava, and at the highest point was an 

 immense quantity of sulphur, which had been thrown out at a somewhat late 

 period. The summit contained a crater. 



Situated in a still lower latitude are the seven hills, or Jebal Sebar or Saabe, 

 all equally of volcanic origin, of ancient date, and forming some very fine 

 craters, one in particular, receiving the name of the basin island, from its 

 very perfect form. A few also are curious from their precipitous appearance, 

 and of course all of ancient volcanic rocks. In short, the only modern one in 

 this respect is the Jebel Teir or Tor above mentioned. 



It may be remarked, that all the rocks in this sea shelve very precipitously, 

 in many no ground being found at 240 fathoms even at the eilge, thus exem- 

 plifying their perpendicular height. These are all volcanic, as also are all those 

 from Jidda to the Straits ; but above the former place, they are chiefly coral, 

 yet equally precipitous on all sides. Arkeeko, N. Lat. 15° 33', E. Long. 39° 31', 

 may be cited as an other interesting remain, from the beautiful and safe 

 haven it affords, being a mere ring of rocks, deficient only at one small spot, 

 serving as an entrance to the bay. 



It may also be interesting to note, that many coral rocks occur in this quar- 

 ter besides those in other places, quite close to what are undoubtedly volcanic. 

 Moreover, that an immense or even unfathomable depth is equally found 

 close to the one as to the other, which circumstance would lead to the con- 

 elusion of its not being unlikely that what we call coral rocks, are merely in- 

 crustations of corals upon volcanic rocks, which had never reached the sur- 

 face. 



A circumstance, and in favour of the opinion of many geologists, perhaps it 



