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…vapours, baths; winding labyrinths, also every where obvious; as Kircher with greatest diligence observed; and gapes with burrow’d breathing-holes, which when they send forth a blast, presently, no without terrour of standers-by, are perceived more inward crackings, as it were, of burning and blazing fires, and sounds of waters; as in the Phlegraean…
https://www.wichita.edu/academics/fairmount_las/geology/wparcell/Kircher/volcanoes/chapter3.php