LURAY CAVERN  , a large

cave in Page county, Virginia, U.S.A., 390 35' N. and 78° 17' W., near the village of Luray, on the Norfork & Western railway . The valley, here ro m. wide, extends from the Blue Ridge to the Massanutton Mountain . The ridges lie in vast folds and wrinkles; and elevations in the valley are often found to be pierced by erosion . Cave Hill, 300 ft. above the water-level, had long been an object of local interest on account of its pits and oval hollows or sink-holes, through one of which, on the 13th of August 1878, Andrew J . Campbell and others entered, thus discovering the cavern now described . The Luray cavern does not date beyond the Tertiary period, though carved from the Silurian limestone . At some period, long subsequent to its original excavation, and after many large stalactites had grown, it was completely filled with glacial mud charged with acid, whereby the dripstone was eroded into singularly grotesque shapes . After the mud had been mostly removed by flowing water, these eroded forms remained amid the new growths . To this contrast may be ascribed some of the most striking scenes in the cave . The many and extraordinary monuments of aqueous energy include massive columns wrenched from their place in the ceiling and prostrate on the floor; the Hollow Column, 40 ft. high and 30 ft. in diameter, standing erect, but pierced by a tubular passage from top to bottom; the Leaning Column nearly as large, undermined and tilting like the campanile of Pisa; the Organ, a cluster of stalactites in the chamber known as the Cathedral; besides a vast bed of disintegrated carbonates left by the whirling flood in its retreat through the great space called the Elfin Ramble . The stalactitic display exceeds that of any other cavern known . The old material is yellow, brown or red; and its wavy surface often shows layers like the gnarled grain of costly woods .

The new stalactites growing from the old, and made of hard carbonates that had already once been used, are usually

white as snow, though often pink, blue or amber-coloured . The Empress Column is a stalagmite 35 ft. high, rose-coloured, and elaborately draped . The double column, named from Professors Henry and Baird, is made of two fluted pillars side by side, the one 25 and and all perfectly translucent . Down the edge of each a tiny rill glistens like silver, and this is the ever-plying shuttle that weaves the fairy fabric . Streams and true springs are absent, but there are hundreds of basins, varying from 1 to 5o ft. in diameter, and from 6 in. to 15 ft. in depth . The water in them is exquisitely pure, except as it is impregnated by the carbonate of lime, which often forms concretions, called according to their size, pearls, eggs and snowballs . A large one is known as the cannon ball . On fracture these spherical growths are found to be radiated in structure . Calcite crystals, drusy, feathery or fern-like, line the sides and bottom of every water-filled cavity, and indeed constitute the sub- the other 6o ft. high, a mass of snowy alabaster . Several stalactites in the Giant Hall exceed 50 ft. in length . The smaller pendants are innumerable; in the canopy above the Imperial Spring it is estimated that 40,000 are visible at once . The " cascades " are wonderful formations like foaming cataracts caught in mid-air and transformed into milk-white or amber alabaster .

The

Chalcedony Cascade displays a variety of colours . Brand's Cascade, the finest of all, is 40 ft. high and 30 ft. wide, and is unsullied and wax-like white, each ripple and braided rill seeming to have been polished . The Swords of the Titans are monstrous blades, eight in number, 5o ft. long, 3 to 8 ft. wide, hollow, 1 to 2 ft. thick, but drawn down to an extremely thin edge, and filling the cavern with tones like tolling bells when struck heavily by the hand . Their origin and also that of certain so-called scarfs and blankets is from carbonates deposited by water trickling down a sloping and corrugated surface . Sixteen of these alabaster scarfs hang side by side in Hovey's Balcony, three white and fine as crape shawls, thirteen striated like agate with every shade of brown, Scale 500 ft. to the inch . 19 . Chalcedony Cascade . 20 . Coral Spring . 21 . The Dragon . 22 .

Bootjack

Alley . 23 . Scaly Column . 24 . Lost Blanket . 25 . Helen's Scarf . 26 . Chapman's Lake . 27 . Broaddus Lake . 28 .

Castles on the

Rhine . 29 . Imperial Spring . 30 . The Skeleton . 31 . The Twin Lakes . 32 . The Engine Room . 33 . Miller's Room . 34 .

Hawes Cabinet . 35 . Specimen Avenue . 36 . Proposed Exit.stance of which they are made . Variations of level at different periods are marked by rings, ridges and ruffled margins . These are strongly marked about Broaddus Lake and the curved ramparts of the Castles on the Rhine . Here also are polished stalagmites, a rich buff slashed with white, and others, like huge mushrooms, with a velvety coat of red, purple or olive-tinted crystals . In some of the smaller basins it sometimes happens that, when the excess of carbonate acid escapes rapidly, there is formed, besides the crystal bed below, a film above, shot like a sheet of ice across the surface . One pool 12 ft. wide is thus covered so as to show but a third of its surface . The quantity of water in the cavern varies greatly at different seasons . Hence some stalactites have their tips under water long enough to allow tassels of crystals to grow on them, which, in a drier season, are again coated over with stalactitic matter; and thus singular distortions are occasioned .

Contiguous stalactites are often inwrapped thus till they assume an almost globular

form, through which by making a section the primary tubes appear . Twig-like projections, to which the term helictite has been applied by the present writer, are met with in certain portions of the cave, and are interesting by their strange and uncouth contortions . Their presence is due to lateral outgrowths of crystals shooting from the side of a growing stalactite, or to deflections caused by currents of air, or to the existence of a diminutive fungus peculiar to the locality and designated from its habitat Mucor stalactitis . The Toy-Shop is an amusing collection of these freaks of nature . The dimensions of the various chambers included in Luray Cavern cannot easily be stated, on account of the great irregularity of their outlines . Their size may be seen from the diagram . But it should be understood that there are several tiers of galleries, and the vertical depth from the highest to the lowest is 26o ft . The large tract of land owned by the Luray Caverns Corporations covers all possible modes of entrance . The waters of this cavern appear to be entirely destitute of life; and the existing fauna comprises only a few bats, rats, mice, spiders, flies and small centipedes . When the cave was first entered, the floor was covered with thousands of tracks of raccoons, wolves and bears—most of them probably made long ago, as impressions made in the tenacious clay that composes most of the cavern floor would remain unchanged for centuries . Layers of excrementitious matter appear, and also many small bones, along with a few large ones, all of existing species . The traces of human occupation are pieces of charcoal, flints, moccasin tracks and a single skeleton embedded in stalagmite•in one of the chasms, estimated, from the present rate of stalagmitic growth, to have lain where found for not more than five hundred years .

The temperature is uniformly 540 Fahr., coinciding with that of

Mammoth Cave, Kentucky . The air is very pure, and the avenues are not uncomfortably damp . The portions open to the public are now lighted by electric lamps . The registered number of visitors in 1906 was 18,000 . A unique and highly successful experiment merits mention, by which the cool pure air of Luray Cavern is forced through all the rooms of the Limair sanatorium erected in 1901, by Mr T . C . Northcott, president of the Luray Caverns Corporation, on the summit of Cave Hill . Tests made for several successive years by means of culture media and sterile plates, demonstrated the perfect bacteriologic purity of the air, first drawn into the caverns through myriads of rocky crevices that served as natural filters, then further cleansed by floating over the transparent springs and pools, and finally supplied to the inmates of the sanatorium . For a full description see an article by Dr G . L . Hunner, of Johns Hopkins University, in the Popular Science Monthly for April 1904 . (H .

C .