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…up and down with so great a security: The Earth as hot, as sufferable, being hollow underneath; where the Fire and Water make a horrible rumbling, conjoining together, as if one were fuel to the other: here and there bubling up, as such time as the Sea is inraged with tempests. In some places; of the colour of Water, which is mingled with Soot; in other, as …
https://www.wichita.edu/academics/fairmount_las/geology/wparcell/Kircher/volcanoes/chapter5.php