Edmond Halley's version of this theory, which hypothesized that escaping gas created the Aurora Borealis, was functionally disproved by Nevil Maskelyne and Charles Hutton's Schiehallion experiment. For 10 points each:
[10e] Name or describe this crank geophysical theory propounded in the 19th century by John Cleves Symmes, who described a series of concentric shells connected by holes at the North and South Poles.
ANSWER: Hollow Earth [accept descriptive answers indicating that the Earth has some sort of significant interior space]
[10m] Predecessors to the Hollow Earth theory include classical myths about caves leading to the underworld; for example, in the Aeneid, Aeneas and the Cumaean Sibyl descend through a cave near this volcanic crater lake in southern Italy.
ANSWER: Lake Avernus [or Lago d'Averno]
[10h] In Hindu cosmology, asuras and nagas inhabit the seven levels of this subterranean region, located below the earthly realm of Prithvi and above the hellish Naraka.
ANSWER: Patala [or Patalaloka; prompt on Nagaloka]
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