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SCIENCE-GOSSIP. 



All of the gorges of Malta and Gozo possess 

 similar scenic characters, and all apparently owe 

 their origin to the same or to analogous causes. 

 They form the main lines of drainage of the 

 islands ; and all cut deep down into the Lower 

 Coralline limestone, the basement bed of the 

 Maltese series. Their general configuration, their 

 accumulations of rounded boulders, undercuttings, 

 long curvilinear groovings, and the conglomerates, 

 with their contained hippopotami and elephantine 

 remains, that are invariably found in the vicinity 

 of the gorge mouths, appear to indicate the former 

 action of considerable bodies of running water. 

 Still, the absence of fluviatile remains and the 



levels in their cliff-like sides, and to break off and 

 transport blocks of limestone of considerable size. 



The cliff-bound coastline of L'Ahmar, on the 

 north-western shore abounds with caverns in 

 which myriads of gulls and other sea-birds find a 

 home. At Niescfa there is a spacious marine cave 

 which has been eroded out of the Coralline lime- 

 stone by wave action. It is one of many that 

 occur in the neighbourhood. The entrance, which 

 is situated at the sea-level, is but a small one, and, 

 when the Levante blows, the swell of the waves 

 surges through it and thunders onwards into its 

 depths. The air, which is thus imprisoned and 

 compressed, produces a concussion resembling the 



La Fenestra Azzurra, Gozo. 

 (Lower Coralline Limestone.) 



limited hydrographical areas of the gorges render 

 it difficult to conceive that any of them ever 

 formed the bed of a permanent stream. Their 

 physical features and the position and arrangement 

 of the organic remains found in them point to the 

 agency of powerful torrents of water that swept 

 them periodically at a time when the Maltese area 

 formed a portion of the great land barrier between 

 Europe and Africa, and when the climate and 

 rainfall were different to those that now endure. 

 The power and volume of these rapid torrents were 

 such as to cut deep canon-like gorges, with vertical 

 escarps of from fifty to a hundred feet in height, 

 from out the massive and compact Lower Coralline 

 limestone ; to form long undercuttings at various 



muffled roar of a volley of artillery, and the sounds 

 are projected to a considerable distance in the 

 neighbourhood. Within, the cavern attains to 

 spacious proportions, but as it has been eroded 

 out of a perpendicular cliff face, the entrance is 

 only accessible in fine weather by means of a 

 boat. When the waters are calm it is possible 

 to penetrate to all the branches ; but the under- 

 taking is always both difficult and dangerous, 

 owing to the sunken rock masses which impede 

 the navigation of the passages. Looking from the 

 interior seawards the vista revealed through the 

 irregularly-shaped contracting walls of the main 

 gallery is very imposing and picturesque. Through- 

 out its length the roof and walls are fissured and 



