On the south side of the Grand Arch are several known caves. The curator has been lowered about 100 feet into one of small dimensions, with a large chamber from it, containing many sonorous stalactites of large proportions, as well as much elaborate formation. Next to this is a cavern called the Specimen Cave. It is about 20 feet deep, with a large number of bones on the floor, which has been broken away. The fracture shows that it was largely composed of red clay. The broken face is full of bones. This cave would be worth special examination, because it is believed many of the bones belonged to animals which have disappeared from New South Wales. Farther on is a cave into which, five years ago, the curator was lowered about 240 feet. At a still greater distance, three miles from the Cave House, is a cave, with a strong stream of water flowing out of it. That is the farthest limestone visible on this side of the mountain. The stream sinks into the ground at a short distance after it leaves the mouth of the cave. It is believed that this water runs underneath all the caves on the south side into the Lucas Cave, and is not seen again until it re-appears under "The Bridge." The range of limestone rocks seen from the Cave House extends north and south five-and-a-half or six miles. At each end water in considerable volume sinks into the earth suddenly and re-appears in caves near the centre of the valley; the northern stream flowing through the Imperial Cave, and the southern through the Lucas Cave. Both streams come to the surface in Camp Creek, and chatter away towards the sea. CHAPTER XXXI. CONCLUSION. The journey from Sydney to the Caves is long and expensive, but the route is interesting all the way. Thirty-six miles from the city after crossing the Emu Plains and the magnificent bridge over the Nepean at Penrith, 87 feet above sea-level, the train begins to climb the mountain range, and after travelling 52 miles it attains an altitude of 3,658 feet. The first zigzag up Lapstone Hill brings into view a splendid panorama, and, notwithstanding the disregard of railway surveyors for fine scenery when it is placed in the balance against economical construction, there are many glorious glimpses to be obtained from the carriage windows during the journey between Sydney and Tarana. If the traveller has time to stop _en route_ he will find much to interest him round about Lawson and Katoomba, Blackheath and Mount Victoria. The great Zigzag into the Lithgow valley is one of the most remarkable feats of engineering in the world. There is a fall of about 230 yards in five miles of running. Even after this sudden descent the country is still very elevated, and at Tarana, where it is necessary to take coach for the Caves, it is upwards of 2,500 feet above the level of the sea.