THE EARTH. 1R7 



force enough to push its weeds and sliclls, by insensible ap- 

 proaches, to the shore. 



There are other shores, beside those already described, which 

 either have been raised by art, to oppose the sea's approaches, 

 or, from the sea's gaining ground, are threatened with imminent 

 destruction. The sea's being thus seen to give and take away 

 lands at pleasure, is, without question, one of the most extraor- 

 dinary considerations in all natural history. In some places it 

 is seen to obtain the superiority by slow and certain approaches ; 

 or to burst in at once, and overwhelm all things in undistinguish- 

 ed destruction ; in other places it departs from its shores, and 

 where its waters have been known to rage, it leaves fields cover 

 ed with the most beautiful verdure. 



The formation of new lands by the sea's continually bringing 

 its sediment to one place, and by the accumulation of its sands 

 in another, is easily conceived. We have had many instances 

 of this in England.* The island of Oxney, which is adjacent 

 to Romney-niarsh, was produced in this manner. This had for 

 a long time been a low level, continually in danger of being over- 

 flown by the river Rother ; but the sea, by its depositions, has 

 gradually raised the bottom of the river, while it has hollowed 

 the mouth ; so that the one is sufficiently secured from inunda- 

 tions, and the other is deep enough to admit ships of considerable 

 burthen. The like also may be seen at that bank called the 

 Dogger-sands, where two tides meet, and which thus receives 

 new increase every day, so that in time the place seems to pro- 

 mise fair for being habitable earth. On many parts of the coasts 

 of France, England, Holland, Germany, and Prussia, the sea 

 has been sens'bly known to retire.^ Hubert Thomas asserts, 

 in his description of the Country of Liege, that the sea formerly 

 encompassed the city of Tongres, which, however, is at present 

 thirty-five leagues distant from it : this assertion he supports 

 by many strong reasons ; and, among others, by the iron rings 

 fixed in the walls of the town, for fastening the ships that came 

 into the port. In Italy there is a considerable piece of ground 

 gained at the mouth of the river Arno ; and Ravenna, that once 



* It is supposed that there existed an istlimus between Great Britain and 

 l-'rame, whidi is conceived to have been broken down by the sea, before tho 

 commentciiient of any accurate historical records lespectii'g the^c islaiida 

 ."i rinfton, vol. vi. p. KX. 



