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journey over Assuay is formidable^ especially in 
the months of June, July^ and August, when 
there are immense falls of snow, and the icy 
winds of the south sweep over these regions. 
As the high road, according to the measures I 
took in 1802, is almost the height of Mount 
Blanc, the travellers are exposed to a cold so 
excessive, that several perish every year from its 
effects. In the middle of this journey, at the ab- 
solute height of four thousand metres, we cross 
a plain, the extent of which is six square 
leagues. This plain (and this remarkable fact 
throws some light on the formation of elevated 
plains) is almost on the level of the savannahs, 
by which the part of the volcano of Antisana 
covered with eternal snows is surrounded. The 
elevated plains of Assuay and of Antisana, the 
geological construction of which has such strik- 
ing resemblances, are nevertheless more than 
fifty leagues distant from each other : they con- 
tain lakes of fresh water of considerable depth,' 
and bordered by a thick turf of Alpine grasses, 
but no fish, and scarcely any aquatic insect, en- 
livens their solitude. ^ 
The soil of the Llano del Pullal, the name 
given to the high plains of Assuay, is excessively 
marshy. We were surprised to find in this 
place, and at heights which greatly surpass the 
top of the Peak of Teneriffe, the magnificent re- 
VOL XIII. R 
