Featured on PDR in the collection Alexander in the Bathysphere

While the bathysphere was not named until the 1930s (“bathy” from the Greek prefix for deep), humans may have been using diving bells for millennia. In the Problemata, a text contentiously credited to Aristotle, the philosopher tells how his student Alexander the Great descends to the depths of the sea in “a very fine barrel made entirely of white glass”, as a later poet would put it. The reasons for this descent differ across time. For some, it was to scout submarine defenses surrounding the city of Tyre during its siege. Others depict the Macedonian king met with a cruel vision of the great chain of being, stating, upon resurfacing, that “the world is damned and lost. The large and powerful fish devour the small…