54 



and above all to substitute for them, where the 

 cultivation of the country permits, trigonometric 

 operations. On the two borders of the llanos, 

 that extend like a gulf from the delta of the 

 Oroonoko to the snowy mountains of Merida, 

 two granitic chains, toward the north and to- 

 ward the south, stretch parallel to the equator. 

 These ancient coasts of an interior basin are 

 visible from afar in the steppes, and might serve 

 to establish signals. The Peak of Guacharo, 

 Cocollar, and Tumiriquiri, the Bergantin, the 

 Morros of San Juan and San Sebastian, the Ga- 

 lera, that bounds the llanos like a rocky wall, 

 the little Cerro de Flares which I saw at Cala- 

 bozo, and this at a moment when the mirage 

 was almost null, will serve for the series of 

 triangles toward the northern limit of the plains. 

 A great part of these summits is visible at the 

 same time in the llanos, and in the cultivated 

 stripe of the coast. Toward the south the gra- 

 nitic chains of the Oroonoko or the Parima are 

 a little distant from the borders of the steppe, 

 and less favorable to geodesic operations. The 

 mountains however, that rise above Angostura 

 and Muitaco, the Cerro del Tirano near Cay- 

 cara, the Pan de Azucar, and Sacuima near 

 the confluence of the Apure and the Oroonoko, 

 may be very useful ; especially if the angles be 

 taken in cloudy weather, so that the play of 

 extraordinary refractions over a soil strongly 



