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… flames of Fire; to the astonishment of all Beholders; that its Soyl springs abundantly with often and eternal Burnings: Yet those subterraneous fountain of Fire, that continually feed and supply these Vulcano’s; and the abundance of fat, oily sulphureous, and inflammable matter and fuel, or nourishment, wherewith the whole Country thereabouts, and all the…
https://www.wichita.edu/academics/fairmount_las/geology/wparcell/Kircher/volcanoes/chapter6.php