Æthna

Historical definition

Æthna is invisible, sulphurous subterranean fire, which burns stones into coals like jet in mountains full of resin and bitumen.

Meaning

The entry gathers several features into an account of underground burning: hidden fire, sulphurous character, combustible mountain materials and stone altered into a coal-like product. Jet appears as a comparison within that account. The definition should not be reduced to the name of an ordinary furnace, because its setting and agency are natural and subterranean.

Its descriptive language also differs from a modern geological explanation. We can report how the author connects these materials without turning the sentence into evidence that every dark stone was produced by the same process. For reading purposes, the links among fire, sulphur and earth are more secure than an exact present-day mineral identification.