so Geological Delineation of South Ainertdcti 



zuola, an impetuous current of water must have swept cverv 

 thin'j:; along with it; and the present sea presents large spaces 

 without isTauds : instead of islands there are in the Llanos 

 uhole uninterrupted portions of from 200 to 300 square 

 miles of surface which rise from two to five feet above the 

 plain, and which are called vwsaa or bancos 5 which is a^ 

 much as to sav, that they were shoals or sand -banks in the 

 antient sea. I must here observe, that the middle of the 

 plain of Orinoco is the most beautiful and levcllest part of 

 it. The bottom of this immense bason rises up and becomes 

 unequal at the edge; the plains therefore which one tra- 

 verses between Guyana and Barcelona are less perfect and 

 level than those of Calabozo and Uritucu< 



This remarkable difference which we found between the 

 Cordillera of Venezuola and that of the Cataracts, which is 

 that the latter consist of alluvial mountains entirely bare, is 

 observed between the northern Llano of the Orinoco and that 

 of the Rio Negro and river Amazon. In the former, the 

 orioinal' mountains are every w'here covered with compact 

 limestone, gypsum, and sandstone : in the latter the gra- 

 nite every where appears. The more one approaches the 

 c.'juator the thinner is the stratum of sand which covers the 

 crust of earth on the (M'iginal mountains ; in a laud \\hcre 

 vciretation is so luxuriant, there is seen in the middle of fo- 

 rests spaces of 40,000 square toises scarcely covered with 

 a few lichens, and whicli do not rise two inches above the 

 rest of the surface. Will the same be discovered in Africa? 

 for it is only in America and Africa that there is land under 

 the equator. 



Having taken a view of the direction of the mountains 

 and vallcvs, or the farm of the inequalities ot the earth, let 

 us now turn our attention to objects of more importance 

 which have been loss examined, namely, the rising and fall- 

 ing of the strata of the original mountains which form 

 this part of the earth I have traversed. I have been con- 

 vinced since ] 79- that the rising of the original mountains 

 follows a general l:uv. and that, making allowance for those 

 inequalities v. hich may have been produced by trifling local 

 causes, and particularly veins and strata in mines, or by very 

 old valleys, the stratified coarse-grained granite, the foli- 

 ated granite, and particularly the micaceous schist and ar- 

 gillaceous schist, rise in the league 3 J by the miner's com- 

 pass, as they form with the meridian of the place an angle 

 of 52-i^". The falling of 'the strata is towards the north- 

 west ; that is to sa)-, they fall parallel with a body that 

 might be thrown in the same directioji, or the aperture of 



