[ 30 ] 
whether borelli, or any other of its hifloriographers, 
takes notice of any fa6t, by which this conjedture is 
proved. The fame feems alfo probable, for fimilar rea- 
fons, of mount Hecla, the Pic of Tenerif, See. And if 
this be true of lingle or ifolated volcanos, like Vefuvius 
and .Ttna, that carry fuch ftrong external marks of hav- 
ing been exclufively produced by the accumulated lava 
of eruptions, much more is it likely to be fo of others, 
that are not only conhderably higher, but form parts of 
a continued chain, like the volcanos of the Andes, as I 
imagine. Is it not, moreover, highly improbable, that 
Chimborofo, which is one of thofe volcanos, and the 
higheft mountains in the known globe, meafuring, ac- 
cording to the French academicians, 3220 toifes, which 
exceed four Italian miles, allowing 764 toifes to a mile; 
is it not, I fay, highly improbable, that fuch a mountain 
Ihould exclufively owe its origin and formation to the 
accumulated materials of eruptions only ? May not the 
fame be faid of the mountains Antifana, Kotopaefi, Pi- 
chincha, and the other volcanos of the Andes, of which 
fome are little inferior in height to Chimborofo, and 
conftitute in general the higheft parts of that vaft chain ? 
And though the fummits of thefe mountains, in all pro- 
bability, form ifolated points, yet, I prefume, they unite 
in an uninterrupted mafs below, like other chains of 
mountains. irAnd if this be true, it is hardly credible, 
that the mafles where thefe volcanos refpedtively exift, 
call have been indebted folely to them for their origin, 
or that they can have been fortuitoufly caft up from the 
7 bowels 
