[ 54 ] 
P, S. If it flioiild be afked, how a perfon, cither 
to their feet or in {looping or laying down to make 
the obfervations, could endure fuch a degree of heat; 
I anfwer, that the heat, both at top and in the mouth 
of the mountain, was only in particular places. This 
was known by the fumes ; the hard maflcs of lava 
are only warm, and even fo tolerable as to permit me, 
to lay on them, as I was often obliged to do, when 
the thermometer was immerged, to make a true 
obfervation. 
V. Dc. 
