MOUNTAIN OF THE BELL. 287 



state of decay. A few miles to the north, and 

 within a short distance of the sea, lies the Gebel 

 Narkous or Mountain of the Bell, which is said to 

 emit a sound " sometimes resembling musical 

 glasses, sometimes like one piece of metal struck 

 against another." This phenomenon is variously 

 explained by travellers. The Arabs believe that 

 the bell belongs to a convent buried under the sand. 

 The Greeks have their legends about saints, de- 

 mons, and genii, who celebrate their respective mys- 

 teries under this incomprehensible precipice. Mr 

 Fazakerley says the sound was louder or softer, ac- 

 cording as the sand was more or less pressed ; and 

 that at the same time a quivering or vibration was 

 very sensibly felt. Burckhardt observed nothing that 

 could throw any light on it j nor did he discover the 

 slightest mark of volcanic action, to which he sup- 

 posed the thundering noise might be attributable. 

 Perhaps the miracle may be explained by the exist- 

 ence of a cavity underneath, in which steam or rare- 

 fied air is generated ; or by the moving of the fine 

 white sand, of which the bank is composed, over the 

 moister and harder sand beneath.* 



* Similar sounds are not uncommon in other parts of the world 

 (See Edinburgh Cabinet Library, No. X. pp. 235-36). In a paper 

 lately read before the Geological Society in London, Sir John 

 Herschel suggests as the only probable explanation which occurred 

 to him of the sounds at Narkous, that they are caused by the ge- 

 neration and condensation of subterraneous steam ; and belong to 

 the same class of phenomena as the combustion of a jet of hydro- 

 gen gas in glass tubes. He makes the general remark, that 

 wherever extensive subterraneous caverns exist, communicating 

 with each other or with the atmosphere by means of small orifices, 

 considerable difference of temperature may occasion currents of 

 air to pass through those apertures with sufficient velocity for pro- 

 ducing sonorous vibrations. The sounds described by Humboldt, 

 as heard at sunrise by those who sleep on certain granitic rocks on 

 the banks of the Orinoco, may be explained on this principle. 



