George Maw — Notes on the Mediterranean. 549 



Corsica, and the adjacent islands of Elba, Capriera, and Monte- 

 Christo, are also remarkable for the absence of cliffs, and are want- 

 ing in those abrupt escarpments separating land and water which 

 are so abundant on our own coasts. Their aspect is that of moun- 

 tain to]DS rising out of the sea, suggesting to the eye the seaward 

 prolongation of their sub-aerial contour of sloping hill-sides and 

 river-cut valleys, as though the sea had not stood sufficiently long at 

 its present level to excavate an escarpment. The deep intersecting 

 bays that occur along the coast from Marseilles to the Eeviera, sug- 

 gest the same conclusion, the undulating land surface spreading 

 down to the water's edge, and the deep bays running up the inter- 

 vening valleys, which must have had an origin common with that 

 of their landward prolongations. 



One of the most noticeable of these inlets, is the Etang de Berre, 

 skirted by the railway between Aries and Marseilles. It has a 

 superficial area of about 90 square miles. It is entirely land-locked, 

 shut in by high ground of Jurassic limestone, and connected with 

 the sea by only a very narrow outlet. There is an absence of cliff 

 structure on its border, to which the surrounding land slopes down 

 in gentle undulations. The sea cannot have effected its excavation 

 through the existing narrow channel, and its basin must be a valley 

 of sub-aerial denudation, into which the salt water has recently 

 entered from the Mediterranean on the subsidence of the land. It 

 is altogether different in character from the Stagnos or salt-water 

 lakes on the low coasts. The almost complete isolation of this 

 curious sheet of water suggests an affinity with the salt lakes of 

 Algeria and other parts bordering on the Mediterranean coast, in- 

 cluding perhaps the Dead Sea ; all of which, probably, owe their 

 saline character to connexion at some time with the Mediterranean. 

 The various heights at which they occur both above and below the 

 sea-level, and the various degrees of concentration of saline ingre- 

 dients, in relation to the surrounding areas of drainage, involve 

 intricate questions bearing on the changes of level and relative 

 antiquity of the movements, which it would be of the greatest 

 interest to carefully work out. 



2nd. The Inset Current from tie Atlantic — Several theories have 

 been offered in explanation of the causes inducing the current that 

 sets in towards the Mediterranean through the Straits of Gibraltar. 

 Keceiving as it does the sub-aerial drainage of more than a third of 

 Europe and a large area of Africa, the natural inference is, that its 

 accumulation would pass outwards through the Straits, and it has 

 been suggested that a deeper return current towards the Atlantic 

 compensates for the influx on the surface.^ 



Another theory is, that evaporation reduces the water of the Medi- 

 terranean at a greater rate than the supply from river drainage. 

 This, however, would only be tenable supposing the area of evapo- 



1 Sir C. Lyell stated in the discussion that the existence of a reverse current at a 

 greater depth had heen disproved. 



