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… and stretch’d forth all along, descending into the inmost Abysses, without bottom or end; are more frequent. Which as they have swallowed up very many, unadvisedly coming near to view without a guide; so have, by their ruine, left an example to others; not rashly to venture upon those places, which by such occult Artifices and Machines, and hidden deceipts …
https://www.wichita.edu/academics/fairmount_las/geology/wparcell/Kircher/volcanoes/chapter6.php