NATURAL BRIDGES—ANDES. O27 
eades where it enters the chasm, and where it again 
escapes from it. A natural arch, 474 feet in length 
and 39 in breadth, stretches across the fissure at 
a height of 318 feet above the stream. Sixty-four 
feet below this bridge is a second composed of three 
enormous masses of rock, which have fallen so as to 
‘support each other. In the middle of it is a hole 
through which the bottom of the cleft is seen. The 
torrent, viewed from this place, seemed to flow 
through a dark cavern, whence arose a doleful 
sound, emitted by the nocturnal birds that haunt 
the abyss, thousands of which were seen flying over 
the surface of the water, supposed by Humboldt 
from their appearance to be goatsuckers. 
In the kingdom of New Grenada, from 2° 30’ toe 
5° 15’ of north latitude, the cordillera of the Andes 
is divided into three parallel chains. The eastern 
one separates the valley of the Rio Magdalena from 
the plains of the Rio Meta, and on its western de- 
clivity are the natural bridges of Icononzo above 
mentioned. The central chain, which parts the 
waters between the basin of the Rio Magdalena 
and that of the Rio Cauca, often attains the limits 
of perpetual snow, and shoots far beyond it in the 
colossal summits of Guanacas, Baragan, and Quin- 
diu. The western ridge cuts off the valley of Cauca 
from the province of Choco and the shores of the 
South Sea. In passing from Santa Fe to Popayan 
and the banks of the river now mentioned, the tra- 
veller has to descend the eastern chain, either by the 
Mesa and Tocayma or the bridges of Icononzo, tra- 
verse the valley of the Rio Magdalena, and cross the 
central chain, as Humboldt did, cis the mountain of 
Quindiu. 
