Camping and woodcraft - Scoutmastercg.com

CAVE EXPLORATION 347a stalagmite will join, forming a pillar. If theseepage from above exudes chiefly through a long fissure,the dripstone will join along- this line intoa solid partition. In this way small chambers areformed out of large ones, passages are obstructed,defiles are closed, ceilings and floors grow towardeach other, until finally a whole cavern may beclosed up by the same process that started its excavation.Dripstone is the general name given to all depositsmade by dripping water, regardless of theirforms and composition. Originally it is nothingbut soft sulphate or carbonate of lime, with perhapsa trace of iron or other metal soluble in carbonicacid. Gradually it hardens into gypsum oralabaster or calcite, as the case may be. Often itscrystalline forms are of great beauty, both in structureand in coloration. The shapes that dripstoneassumes in stalactites, in pillars, and on cavernwalls, are as varied as those in a kaleidoscope, rangingfrom delicate filigree to baronial ruins, fromboiling" springs or cascades of water to imitations ofanimals or grotesque figures suggesting phantasm^of mythology.The thickness of dripstone is a very uncertainmeasure of the age of a deposit. Limestone rocksvary in composition and in the solubility of theirlime. Underground waters vary in their percentageof carbonic acid, from weak solutions to those thateffervesce and have an acid taste. The rate ofseepage varies. So a stalagmite may grow at therate of nearly an inch a year, for a time, and afterwardless than that in ten or twenty or fifty years.How TO Explore.—Before trying to explore acavern it is advisable to study the topography ofthe surrounding country. Note where the mainstream of the district lies. Its level determineshow deep the cave can possibly go. The thicknessof the limestone bed above that level shows themaximum possible altitude of the cave chambers.