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Eiiganean inountains, or the trappean hills of 
Bohemia. The granites^ the micaceous schists, 
the old sand-stones, the calcareous formations, 
which the mineralogists designate under the 
names of formations of the Jura, of the High 
Alps, or transition limestone, give a particular 
character to the outline of the great masses, and 
to the breaches found on the ridges of the Andes, 
the Pyrenees, and the Uralian mountains. The 
nature of the rocks has every where modified the 
external form of the mountains. 
Cotopaxi, the summit of which is represented 
in the tenth plate, is the loftiest of those volca- 
noes of the Andes, which at recent epochs have 
undergone eruptions. Its obsolute height is five 
thousand seven hundred and fifty- four metres 
(two thousand nine hundred and fifty-two toises); 
it is double that of Canigou ; and consequently 
eight hundred metres higher than Vesuvius 
would be, were it placed on the top of the Peak 
of Teneriffe. Cotopaxi is also the most dread- 
ful volcano of the kingdom of Quito, and its ex- 
plosions the most frequent and disastrous. The 
mass of scoriae, and the huge pieces of rock 
thrown out of this volcano, which are spread 
over the neighbouring valleys, covering a surface 
of several square leagues, would form, were they 
heaped together, a colossal mountain. In 1738, 
the flames of Cotopaxi rose nine hundred metres 
above the brink of the crater. In 1744, the 
