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coming in. I endeavoured to advance to the right of 
the cave, but the heat was fo violent, that it ffopt my 
breath. 
It appeared to me pretty extraordinary, that in one 
and the fame cave, 300 feet under-ground, there 
fhould be fuch a ftifling heat on one fide, and on 
the other fuch an agreeable frefh air. Perhaps the 
cool fide anfwers to fome vent, or communicates 
with the great cleft by fome unknown channel, thro’ 
which the outward air penetrates and cools the 
place. 
In coming out we took care to reff a considerable 
time in the fecond cave, to let the violent heat go off, 
and to dry our fliirts, that were foaked through with 
fweat. We brought away fome of the incruftations, 
and fome of the aluminous fait, which I found to be 
a true alum. 
When we came out, I perceived two remarkable 
things upon my waiftcoat j firff, that the filver lace 
was gilt, and looked like tarnifhed gold lace : but 
this I was not furprized at, as I knew, that fulphur 
mixed with fait of tartar will produce that effed: : 
fecondly, that the drops of water, which were fallen 
upon me, were by the heat of the cave turned to alum, 
and had dried and fattened upon my cloaths. In 
this cave we found the fame forts of earth as we had 
met with at the three fprings of the river of Galleons, 
as I mentioned above. They dyed our fingers, and 
were tattelefs, as the former. This is all I obferved 
in the interior cave. 
We fpent the night in the great cavern. I had 
brought with me a thermometer and a barometer ; 
but this laff was broke by the way, fo that I could 
4 D 2 make 
