This cavern is about 25 feet by 35 feet, and from 2 feet to 10 feet high. From it there is a fall of about 20 feet, opening into another chamber, to the left of which is a pretty fimbriated tray, 10 feet by 12 feet, filled with little knobs of formation, with points so sharp that any pressure of the hand would cause pain. These nodes and points are almost as clear and spotless as the drops of a glass chandelier before they have been converted into fly-walks. Then there is another tray or basin with looped edges containing crystals which are a little "off colour;" and yet another, with escalloped border and formation of a milky hue—that is, pure milky—opaque white, not cerulean blue. This basin is about 14 feet by 16 feet. The roof immediately over the basin is like delicate coral. To the right is a sort of illusion representing solidified water round about black limestone pebbles. This crystal has been formed by a run of water from a rock, the summit of which is about 20 feet away, and which slopes down from the wall at an angle of about 45 degrees.
The sloping rock is beautifully reticulated and marked by curved lines, which gradually diminish towards the base, where the formation changes to nodules and curiously-formed, irregular combinations of the preceding figures massed together. From the ceiling descend various formations of cave decoration, some clear as the skin of a Mayfair beauty at her first ball, others of a delicate fawn colour, and the remainder tinged with oxide of iron. There is a range from the delicate lily of the valley to the rough bronze of the muscular navvy, not to speak of the dusky brown of the unwashed sundowner who arrives at a "station" when "the shades of night are falling fast," and whose motto is not "Excelsior."
The next chamber is about 14 feet by 12 feet, at the end of a slight declivity as white as snow. It is in the form of an ordinary retort, and is succeeded by another chamber of somewhat similar contour, the principal ornamentation being on the floor. Thence the course is upwards, and the most attractive formation is from the roof. The stalactites are in clusters, and for the most part small. Some of them are like twigs, but clear as a limpid stream. Here also are stalagmites about nine inches high, formed on the ends of huge rocks. In addition to these are other smaller stalagmites near to a hole about 14 feet deep, and on the floor are fossil remains. In this hole are passages unexplored. Hard by is a pretty "shawl" hanging from the roof, and beyond it a rock about three feet high, the edge of which is covered with a fine substance like down, which, when blown upon, flies about like the winged seeds of thistles. Descending from this cavern, about 10 yards through a narrow passage, there is a steep fall of nearly 10 feet, which leads to a chamber, the roof of which is about 10 feet high. On the right hand side of this cave are some very white shawl pattern formations and stalactites, and to the left are fine shawls, clear as glass, from four to eight feet long, and from 6 to 12 inches deep. Just beyond is a crisp, velvety floor, like that which characterises a chamber previously described, but not of the same colour. This floor is in some parts very red, as though it had been coloured with clay, and other parts are like glass stained with red ochre. The stalactites are thin, and formed in all sorts of peculiar shapes. The floor is uncommon, being of a piebald character, appearing as though buckets of solution of lime had been cast upon it, in the midst of some large stalactites that give character to the cave, which is about 40 feet by 40 feet. Passing on you come to a pretty chamber ornamented with stalactites, composed mostly of yellow crystal. The cave then runs nobody at present knows where. There are unexplored chambers all around. This cave is named after the Government geologist, and is to be known as the Wilkinson Cave.
Mr. C. S. Wilkinson has contributed some valuable matter to Cave literature. His account of the Jenolan Caves, written for the Government, contains several beautiful passages bearing upon the physical and chemical agencies at work in the formation of limestone caverns. And here it may be interesting to refer to one or two other authorities also on the same subject. Dr. Wright, an American scientist, says, "There can be no doubt that the solvent action of water holding carbonic acid in solution" is the primary agency concerned in the formation of limestone caves. "Limestone," he says, "is not soluble in water until it combines with an additional proportion of carbonic acid, by which it is transformed into the bicarbonate of lime. In this way the process of excavation is conducted until communication is established with running water, by which the mechanical agency of that fluid is made to assist the chemical. Little niches and recesses, which seem to have been chiselled out and polished by artificial means, were formed in this manner; for when these points are strictly examined, a crevice will be observed at the top or at the back of them, through which water issued at the time of their formation, but which has been partially closed by crystals of carbonate of lime or gypsum." Dr. Wright, referring to the different conditions and different periods of cave formation, says:—"The sulphate of lime, which is known under the name of gypsum, plaster of Paris, selenite, alabaster, etc., exerts a much greater influence in disintegrating rock than the sulphate of soda. The avenues in which gypsum occurs are perfectly dry, differing in this respect from those that contain stalactites. When rosettes of alabaster are formed in the same avenue with stalactites, the water which formed the latter has for ages ceased to flow, or they are situated far apart, as the former cannot form in a damp atmosphere."
Mr. Wilkinson also alludes to separate periods of formation in connection with the Jenolan Caves. He says:—"There appear to have been two distinct periods during which stalactitic growth formed; one of comparatively remote age, and very local in character, being chiefly confined to the caves known as the Lurline and Bone Caves; and another but recent and still in operation. The older growth is essentially of a stalactitic type, and the stalactites are remarkably thick, though in one or two cases a huge stalagmite is to be seen. The newer growth exhibits every fantastic and beautiful form known, from the thin hollow reed and transparent veil to the snow-white dome stalagmites, the crystal-fringed pool, the wave-lined floor, and the crooked-fringed shapes that are turned in all directions." But there is one passage in Mr. Wilkinson's account which takes us far beyond the time when the limestone mountains were formed, and describes a complete circle of natural transmutation and reproduction, and which may be appropriately quoted in connection with the cave which bears his name. Here it is:—"First, the decaying vegetation of some ancient forest is invisibly distilling the gas known as carbonic acid; then a storm of rain falls, clearing the air of the noxious gas, and distributing a thousand streamlets of acid water over the surrounding country, and which, as it drains off, not only wears the rocks it passes over, but dissolves them in minute quantities, especially such as contain much lime, and then, laden with its various compounds, flows off to the distant sea, where reef corals, lying in fringing banks round the coast, are slowly absorbing the lime from the water around them, and building the fragile coatings that protect them during life. Slowly as the land sinks the coral bank increases in height, for reef corals can only live near the surface of the water; and soon a considerable thickness has been obtained; while below the upper zone of live corals lies a vast charnel-house of dead coral coverings; then comes a change; suitable temperature, or some other essential condition, fails, killing out all the corals, and through long ages other deposits accumulate over them, gradually crushing and consolidating the coral bank into a firm rock. At last a convulsion of the earth's crust brings it up from the buried depth in which it lies, leaving it tilted on its edge, but still, perhaps, below the surface of the ground; rain, frost, and snow slowly remove what covers it, until it lies exposed again to the sunlight, but so changed that but for the silent but irresistible testimony of the fossil forms of which it is composed, it were hard to believe that this narrow band of hard grey rock was once the huge but fragile coral bank glistening in the bright waters with a thousand hues. And now the process is repeated; the decaying vegetation of the surrounding forest produces the carbonic acid, the rains spread it over the ground, which is now the most favourable for being dissolved, and the consequence is that the acid water saturates itself with the limestone rock, and whenever the least evaporation takes place, has to deposit some of its dissolved carbonate of lime in one of the many stalactitic forms, before it can flow off to the sea and distribute its remaining contents to fresh coral banks. Thus the old coral reef melts away far inland, and the lime that formed the coatings of its corals is again utilised for the same purpose. What a simple succession of causes and effects, and yet before the circle is completed long ages of time have come and gone; and what a fine example of the balance between the waste and reproduction that takes place in Nature!" And thus the diurnal motion of the earth and its annual journey round the solar circle, as well as the repetitions of history, have impressive geological analogies. How many hearts have begun to beat—how many have throbbed with passion and ambition, and waxed cold as an extinct volcano in the years required to form a small stalactite? How many ages have come and gone since the Jenolan Caves were coral reefs in the azure sea?
