DRIFT ORIGIN. 155 



snch communications, which, when first mentioned, we hardly 

 believe to exist, form the character of the whole river system 

 which we know by the name of the Amazon. And it is not a 

 particular feature, only to be found in the connection of the 

 Rio Negro with the Oronoco through the Cassiquiare, but it is a 

 general fact ; it is the character of the inter-communications of 

 this great river system. All the water from the tributaries of 

 the Amazon, passing from so low a level, covers such an exten- 

 sive tract, that as the water rises or falls, the main river sends 

 branches into its tributaries, as the tributaries send their water 

 into the main stream. 



It requires hardly a further illustration to show how easy 

 must be the communications in that country ; but it is to be 

 forever a water communication. There are such small tracts of 

 continuous land above the water through the whole year, that 

 railroads will forever be out of the question in that country ; 

 and even common roads cannot be used there for extensive 

 travel. Tbe land is generally low. That is one of the peculiar 

 characteristics of the whole country — even and low. Where 

 the banks of the river are most abrupt, where the river has cut 

 new channels, and where, in consequence of these erosions, 

 masses of land have fallen in and formed steep banks, they rise 

 hardly more than thirty or forty feet, at most sixty feet, above 

 the level of the river anywhere. It is probably the most exten- 

 sive and most even plain in the world, unless the great, desert of 

 Africa has as extensive and flat a surface as the valley of the 

 Amazon. 



Geologically speaking, it is the most curious country known 

 to science. The whole of that land consists of materials ground 

 and carried along by the same cause which has accumulated our 

 drift. It is drift, and the similarity to our drift is most striking. 

 All these drift-beds which cover New England, and which form 

 such a rich soil after the large masses of pebbles have been 

 taken out from it — rich because it is the result of the attrition 

 of the most diversified rocks — all that drift is of the same char- 

 acter as the materials which form these Amazonian plains ; and 

 you see at once what singular vistas it opens into the past when 

 we consider the probable causes or forces which have ground 

 these materials to their present condition ; for if our drift has 

 been ground by glaciers, the drift of the Amazon is so like the 



