492 



by a ridge or knot of mountains* known by 

 the names of Altos de las Cocuyzas (845 t.) and 

 the Higuerote (835 t.) between Los Teques and 

 La Victoria, in 69° 80' and 69° 50' of longitude. 

 On the west of this ridge lies the basin, entirely 

 inclosed-}-, of the lake of Valencia or the Valles 

 de Aragua; and on the east, the basin of the Ca- 

 raccas and of the Rio Tuy. The bottom of the 

 former of these basins is from 220 to 250 toises 

 high; the bottom of the latter is 460 toises 

 above the waters of the Caribbean Sea. It re- 

 sults from these measures, that the most western 

 of the two longitudinal vallies of the Cordillera 



* Vol. iv, p. 77, 80. 

 r f This basin contains a small system of inland rivers, which 

 do not communicate with the Ocean. The southern chain 

 of the Cordillera of the shore of Venezuela is so depressed 

 towards the south-west, that the Rio Pao is separated from 

 the tributary streams of the lake of Tacarigua or Valencia 

 (Vol. iv, 149 and 154). Towards the east, the Rio Tuy, 

 which takes its rise on the western declivity of the knot of 

 mountains of Las Cocuyzas, appears at first to throw itself 

 into the vallies of Aragua ; but hills of calcareous tuf, form- 

 ing a ridge between Consejo and Victoria (Vol. iv, p. 80), 

 force it to take its course south-east. In order to rectify 

 what is said above (Vol. iv, p. 162, note *) on the compo- 

 sition of the waters of the lake of Valencia, I shall here men- 

 tion that MM. Boussingault and Rivero found no traces in 

 them of nitre of potash, but of carbonat of soda and of 

 magnesia, muriate of soda and sulfate and carbonate of 

 lime. 



