THE EARTH. 



the volcano before it has time to produce its 

 effects. This extinction, however, is not effected 

 without very great resistance from the fire be- 

 neath. The water, upon dashing into the ca- 

 vern, is very probably at first ejected back with 

 great violence ; and thus some of those amazing 

 waterspouts are seen, which have so often asto- 

 nished the mariner, and excited curiosity. 'But 

 of these in their place. 



Besides the production of those islands by the 

 action of fire, there are others, as was said, pro- 

 duced by rivers or seas carrying mud, earth, and 

 such like substances, along with their currents ; 

 and at last depositing them in some particular 

 place. At the mouths of most great rivers, there 

 are to be seen banks, thus formed by the sand 

 and mud carried down with the stream, which 

 have rested at that place, where the force of the 

 current is diminished by its junction with the 

 sea. These banks, by slow degrees, increase at 

 the bottom of the deep ; the water in those 

 places is at first found by mariners to grow more 

 shallow ; the bank soon heaves up above the sur- 

 face ; it is considered, for a while, as a tract of 

 useless and barren sand ; but the seeds of some 

 of the more hardy vegetables are driven thither 

 by the wind, take root, and thus binding the 

 sandy surface, the whole spot is clothed in time 

 with a beautiful verdure. In this manner there 

 are delightful and inhabited islands at the mouths 

 of many rivers, particularly the Nile, the Po, the 

 Mississippi, the Ganges, and the Senegal. There 

 has been, in the memory of man, a beautiful and 



VOL. I. H 



