296 CLIMATE OF 



sea, about two thousand miles long and seven or eight hundred 

 wide. 



The rivers and mountain-torrents pouring into it on every 

 side, would gradually fill up this great basin ; and the volcanic 

 action still visible in the scoriae of the Tocantins and Tapajoz, 

 and the shattered rocks of Montealegre, would all tend to the 

 levelling of the vast area, and to determining the channels of 

 the future rivers. This process, continuing for ages, would at 

 length narrow this inland sea, almost within the limits of what 

 is now gapo, or flooded land. Ridges, gradually elevated a 

 few feet above the waters, would separate the tributary streams ; 

 and then the eddies and currents would throw up sandbanks 

 as they do now, and gradually define the limits of the river, as 

 we now see it. And changes are yet going on. New islands 

 are yearly forming in the stream, large tracts of flooded land 

 are being perceptibly raised by the deposits upon them, and 

 the numerous great lakes are becoming choked with aquatic 

 plants, and filled up with sediment. 



The large extent of flat land on the banks of the river will 

 still continue to be flooded, till some renewed earthquakes 

 raise it gradually above the waters ; during which time the 

 stream will work for itself a wider and deeper bed, capable of 

 containing its accumulated flood. In the course of ages per 

 haps this might be produced by the action of the river itself, 

 for at every annual inundation a deposit of sediment is formed, 

 and these lands must therefore be rising, and would in time 

 become permanently elevated above the highest rise of the 

 river. This, however, would take a very long time, for as the 

 banks rose, the river, unable to spread its waters over the 

 adjoining country, would swell higher, and flow more rapidly 

 than before, and so overflow a country elevated above the 

 level of its former inundations. 



The complete history of these changes, the periods of 

 elevation and of repose, the time when the dividing ridges 

 first rose above the waters, and the comparative antiquity of 

 the tributary streams, cannot be ascertained till the country 

 has been more thoroughly explored, and the organic remains, 

 which must doubtless exist, be brought forward, to give us 

 more accurate information respecting the birth and growth of 

 the Amazon. 



