Cave

Rock-hollow of natural formation. The agencies by which caves occur are river and sea-erosion during gradual upheaval, landslips, lava-flows and the action of subterranean water. The latter produces the most extensive caves, such as the series at Luray, Va., and the Mammoth Cave, Ky. Fingal's Cave, Scotland, is a noted example of sea-action, and the famous Fo a dell a Palomba of Etna is a lava-cavity, others occurring in Iceland, the Azores, Canary and Hawaiian Islands. For artificial caves see BAMIAN, ELEPHANT A, etc.