Cave

or Cavern, an opening proluced by nature in the solid crust of the earth. Caves are principally met vith in limestone rocks, in gypsum, “ometimes in sandstone, and in volwanic rocks (basalt, lava, tufa, etc.). The most celebrated caverns in the United States are Madison’s Cave, in Rocking ham Co., Va.; Weyer’s Cave, in the same county; Luray Cave, in Page Co., Va.; and the Mammoth Cave, in Edmondson Co., Ky., which incloses an extent of about 40 miles of subterraneous windings. One of its ehambers, called the Temple, is said to cover a space of nearly 5 acres, and to be surmounted by a dome of solid rock 120 feet in height. The Cumber land mountains, in Tenne ee, contain some curious caverns, in one of which, at a depth of 400 feet, a stream was found with a current sufficiently powerful to turn a mill. Another cave in the same State is named Big Bone Cave, from the bones of the mastodon which have there been discovered. In the Raccoon mountains, near the N. W. extremity of Georgia, is a cave called Nickojack Cave, which has been explored to the distance of 3 miles. A stream of considerable size runs through it, which is interrupted by a fall. Caves are sometimes found which exhale poisonous vapors, The most remarkable known is the Grotto del Cane, a small cave near Naples. In Iceland there are many caves, formed by the lava from its volcanoes. In the volcanic country near Rome there are many natural cavities of great extent and coolne , which are sometimes resorted to as a refuge from the heat. In South America is the cavern of Guacharo, which is said to extend for leagues, Caveat. In the United States this name is given to a notice lodged in the patent-office by a person who wishes to patent an invention, but desires to be protected till he has perfected it. It stands good for a year.