THE EARTH. 97 



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, 

 m the memory of man, a beautiful and large island formed 

 in this manner at the mouth of the river Nanquin, in China, 

 made from depositions of mud at its opening : it is not 

 le^s than sixty miles long, and about twenty broad. La Lou- 

 bere informs us,' in his voyage to Siam, that these sand-banks 

 increase every day, at the mouths of all the great rivers in Asia; 

 and hence, he asserts, that the na\agation up these rivers be- 

 comes every day more diiBcult, and will, at one time or other, 

 be totally obstructed. The same may be remarked with regard 

 to the Wolga, which has at present seventy openings into the 

 Caspian sea ; and of the Danube, which has seven into the 

 Euxine. We have had an instance of the formation of a new 

 island not very long since at the mouth of the Humber, in Eng- 

 land. " It is yet within the memory of man," says the relator,* 

 " since it began to raise its head above the ocean. It began its 

 appearance at low water, for the space of a few hours, and was 

 buried again tiU the next tide's retreat. Thus successively it 

 lived and died, until the year iC66, when it began to maintain 

 its ground against tlie insult of the waves, and then first invited 

 the aid of human industry. A bank was thrown about its ris- 

 ing grounds, and being thus defended from the incursions of the 

 sea, it became firm and solid, and, in a short time, afforded good 

 pasturage for cattle. It is about nine miles in circumference, 

 and is worth to the proprietor about eight hundred pounds a 

 year." It would b^ endless to mention aU the islands that have 

 been thus formed, and the advantages that have been derived 

 from them. How ever, it is frequently found, that new islands 

 may often be considered as only turning the rivers from their 

 former bed ; so that in proportion as land is gained at one part, 

 it is lost by the overflowing of some other. 



Little, therefore, is gained by such accession ; nor is there 

 much more by the new islands which are sometimes formed from 



1 Lvttres Cnneuses et Edifiantes, sec. xi. p. 231. 



2 Pliil. Trans, vol.iv. p. 251. 



I 



