146 llISTuKV OF 



beti of the river is usually lower than any part of the valley, 

 l}ut it often happens, that the t-urface of the water is higher 

 than many vl tlic- grvUiids that are adjacent to the banks of the 

 stream. Jf, after inundations, we take a view of some nvei's, 

 we shall find their banks appear above water at a time that all 

 the adjacent valley is overliovved. This proceeds from the tVe- 

 quent deposition of mud, and such like substances, upon the 

 banks, by the rivers frequently overflowing ; and thus, by de- 

 grees, they become elevated above the plain j and the water is 

 often seen higher also. 



Rivers, as every body has seen, are always broadest at tlie 

 mouth, and grow narrower towards their source, jbut what is 

 less known, and probably more deserving curiosity, is, that they 

 run in a more direct channel as they immediately leave their 

 som'ces ; and that their sinuosities and turnings become more 

 numerous as they proceed. It is a certain sign among the sa- 

 vages of North America, that they are near the sea, when they 

 find the rivers winding, and every now and then changing their 

 direction. And this is even now become an indication to the 

 Europeans themselves, in their journeys through those track- 

 less forests. As those sinuosities, therefore, increase as the 

 river approaches the sea, it is not to be wondered at that they 

 sometimes divide, and thus disembugue by different channels. 

 The Danube disembogues into the Euxine by seven mouths j 

 the Nile by the same number ; and the Wolga by seventy. 



The currents' of rivers are to be estimated very differently 

 from the manner in which those writers, who have given us 

 mathematical theories on this subject, represent them. They 

 found their calculations upon the surface being a perfect plain 

 from one bank to the other . but this is not the actual state (jf 

 nature ; for rivers in general, rise in the middle ; and this con- 

 vexity is greatest in proportion as the rapidity of the stream is 

 greater. Any person, to be convinced of this, need only lay his 

 eye, as nearly as he can, on alevel with the stream, and looking across 

 to the opposite bank, he will perceive the river in the niidst to 

 ,be elevated considerably above what it is at the edges. 'I'his 

 rising, in some rivers, is often found to be three feet high ; and 

 is ever increased in proportion to the rapidity of the stream. In 



1 Buffon de I'Icuvib, pubsiin.vul. ii 



