1843.] 229 



ruptly, and apparently to as great a depth beneath the waves. This 

 is the deepest section of the limestone that is to be seen anywhere 

 in the Maltese Islands. 



In Gozo, to the north of the fault, the coral limestone, the yellow 

 sandstone, and the blue clay have not been so much degraded as 

 they have in the south-eastern part of the island of Malta. On the 

 south-western side of Gozo, however, there is a considerable tract 

 from which these upper deposits have been entirely swept away. 

 Throughout the remainder of the island, north of the fault, it is these 

 deposits which form the crests of a number of detached flat-topped 

 hills, rising from 130 to 200 feet above the valleys, these valleys 

 being excavated down to the level of the inferior deposits. The 

 highest level above the sea which any of these crests attain, is about 

 640 feet. All these table-hills have steep, escarped sides, and present 

 perfect sections of the newer series of deposits. Their number and 

 abruptness gives a more diversified and picturesque character to the 

 island of Gozo than belongs to the scenery of the island of Malta. 



It remains to speak of that portion of the two islands which lies 

 between the two faults. To the north of the fault in Malta, it is 

 only the coral limestone, the yellow sandstone, and the blue clay 

 that are visible, with the exception of some of the upper strata of the 

 freestone deposit, which appear in some places on the western coast 

 just above the sea-level. (See Sections I. and IV,) In whatever 

 parts of the sunken tract the softer strata of the above-mentioned 

 newer deposits are exposed to the sea, the coast becomes indented 

 with bays and inlets. It is by this action, partly, that the two deep 

 bays of St. Paul and Melleha, in the north-eastern corner of the 

 island of Malta, have been formed ; but these bays, and also the two 

 valleys that open into these bays respectively, owe their origin prin- 

 cipally to undulations in the strata, the valleys following the course 

 of the troughs in the strata occasioned by the undulations in question. 

 Most of the valleys in the Maltese Islands follow the course of 

 the dip of the strata. Among the Ben-gemma hills lie the valleys 

 of Boschetto and Entahkleb, which are noted for their picturesque 

 scener}'', and also for their fertility. Their fertility is owing to the 

 springs which break out at the outcrop of the blue clay, in conse- 

 quence of its retaining the moisture which fails on the porous sub- 

 stance of the superincumbent coral limestone and yellow sandstone. 

 From one of the springs in the valley of Entahkleb the water is con- 

 ducted by an aqueduct to Valetta. There are no springs in Malta 

 or Gozo, but when there is clay to retain the water. 



The longitudinal gorges of Siggieni in Malta, and of Highin Selim 

 in Gozo, are exceptions to the ordinary direction of the valleys in 

 these islands ; but these hollows appear to be owing to natural rents 

 in the substance of the hard semi- crystalline limestone. On the 

 precipitous sides of these gorges, and at dift'erent levels, horizontal 

 markings are seen, which appear to be the effects of the sea, acting 

 at different epochs of the progressive elevation of the land. Better 

 evidence, however, of these epochs is afforded by the succession of 

 natural terraces which line the face of every hill in these islands. 



