CONNEXION OF THE PLAINS. 95 



and July, communicate with the basin of the Amazon and 

 the Rio Negro, bounded on one side by the Cordillera of 

 Chiquitos, and on the other by the mountains of Parime. 

 The opening which is left between the latter and the 

 Andes of New Grenada, occasions this communication. The 

 aspect of the country here reminds us, but on a much 

 larger scale, of the plains of Lombardv. which also are only 

 fifty or sixty toises above the level o, 53? ocean ; and are 

 directed first from La Brenta to Turin, east and west ; and 

 then from Turin to Coni, north and south. If we were 

 authorized, from other geological facts, to regard the three 

 great plains of the Lower Orinoco, the Amazon, and the 

 Rio de la Plata as basins of ancient lakes,* we should 

 imagine we perceived in the plains of the Rio Vichada and 

 the Meta, a channel by which the waters of the upper 

 lake (those of the plains of the Amazon) forced their way 

 towards the lower basin, (that of the Llanos of Caracas,) 

 separating the Cordillera of La Parime from that of the 

 Andes. This channel is a kind of land-strait. The ground, 

 which is perfectly level between the Guaviare, the Meta, 

 and the Apure, displays no vestige of a violent irruption of 

 the waters ; but on the edge of the Cordillera of JParime, 

 between the latitudes of 4 and 7, the Orinoco, flowing in 

 a westerly direction from its source to the mouth of the 

 Guaviare,* has forced its way through the rocks, directing 

 its course from south to north. All the great cataracts, as 

 we shall soon see, are within the latitudes just named. 

 When the river has reached the mouth of the Apure in tha*; 

 very low ground where the slope towards the north is met 

 by the counter-slope towards the south-east, that is to say, 

 by the inclination of the plains which rise imperceptibly 

 towards the mountains 'of Caracas, the river turns anew and 

 flows eastward. It appeared to me, that it was proper to 

 fix the attention of the reader on these singular inflexions 

 of the Orinoco because, belonging at once to two basins, its 

 course marks, in some sort, even on the most imperfect 

 maps, the direction of that part of the plains intervening 



* In Siberia, the great steppes between the Irtish and the Obi, espe- 

 cially that of Baraba, full of salt lakes (Tchabakly, Tchany, KarasouK, 

 nd Topolony), appear to have been, according to the Chinese traditioi * 

 even within historical times, an inland sea. 



