SUBMAlilNE JSPBINGS. 105 



The Gulf of Argos supplies an example of a very 

 abundant source of fresh-water named Anavolco, and 

 situate 1 between Kiveri and Astros. Ancient writers 

 affirm, though this may be a little uncertain, that it 

 has been in activity some 1700 years. Colonel 

 Leake, a traveller remarkable for his minute observa- 

 tion, informs us that the column of fresh-water 

 appears to be not less than 50 feet in diameter. 

 When the atmosphere was calm he observed that the 

 water rose with such force from the bottom of the sea 

 as to swell the surface, and agitate it in concentric 

 circles to a distance of some hundreds of feet. He 

 attributed this to the embouchure of a subterranean 

 river at the bottom of the sea. 



This phenomenon may, in a certain measure, be 

 compared with that of artesian- wells, now so familiar 

 to us. The water finds its way into the earth by fil- 

 tration tlirough certain permeable strata. These are 

 so enclosed by beds of clay, or other matters not per- 

 meable, that they form conduits which accidentally 

 terminate beneath tlie sea. The fresh-water running 

 in these natural conduits is lighter than salt-water. 

 If it exists in sufficient quantity to prevent its being 

 mixed completely with the latter, it rises to the sur- 

 face on the same principle that oil floats on the 

 suiface of ordinary water. 



It is not surprising, therefore, that we should find 



