[ & 47 ] 
that the fea grows quiet. Thefe feven waves fuccel-- 
fively fill the caverns, which are all along the coaft 
and when the feventh comes to open itfelf, the air 
at the bottom of the caverns being greatly com- 
prefled, adted by its elafticity, and immediately made 
thole fountains and gufhings I have mentioned ; and 
the waters continuing in the caverns, up to the very, 
place of the hole, began to produce that dull noife, 
caufed the emotion or earthquake, and finifhed with 
the violent wind forced up thro’ the hole ; after 
which the water retired into the fea, and having no 
further impelling caufe, on account of the waves,., 
rendered every thing quiet again. 
I obferved, that this phenomenon happened at no 
limited time, but according to the approach of the 
waves, being ftrongly put in motion after the fe- 
venth. I remained near half an hour to obferve it>, 
and nearly followed the courfe of the cavern to its 
entrance, diredted by the difpofition of the coafi. I 
made my negroes go down where the water broke - r 
for they doubted the report of the greatnefs of thefe 
caverns ; and when the fea was calm one of them 
ventured in, but returned very quickly, or he mull 
have perifhed. Therefore I conclude, that, thefe 
fmail earthquakes round the hole, about forty paces 
from the wave, were only caufed by the comprefled 
air in fome great vault about this place, and that by 
its force was driven up the hole that appeared : that 
this air in the caverns, comprefled to a certain de- 
gree, firft caufed the dull noife, by the rolling of the 
waters, which re fi fired in the cavern ; then adting 
more violently, caufed the fmail earthquake, which 
csafed when the wind pafled out of the hole, and 
