I shall never forget that singular chase, which is probably unparalleled in the history of the universe. A prey to anxiety and the most distressing emotions, we did not properly observe the marvellous, the Titanic, I had almost said the diabolical aspect of the country beneath us, and still we could not altogether blind ourselves to it. Colossal jungles, resembling brakes of moss and canes five hundred or a thousand feet in height--creeks as black as porter, gliding under their dank and rotting aisles--mountainous quadrupeds or lizards crashing and tearing through their branches--one of them at least six hundred feet in length, with a ridgy back and long spiky tail, dragging on the ground, a baleful green eye, and a crooked mouth full of horrid fangs, which made it look the very incarnation of cruelty and brute strength--black lakes and grisly reeds as high as bamboo--prodigious black serpents troubling the water, and rearing their long spiry necks above the surface--gigantic alligators and crocodiles resting motionless in the shallows, with their snouts high in the air--hideous toads or such-like forbidding reptiles, many with tusks like the walrus, and some with glorious eyes, crouching on the banks or waddling in the reeds, and so enormous as to give variety to the landscape--volcanic craters, with red-hot lava simmering in their depths, and emitting fumes of sulphur, which might have choked us had we not closed the scuttles--while over all great dragons and other bat-like animals were flitting through the dusky atmosphere like demons in a nightmare. Little by little we gained upon our quarry, but being afraid to run him too close for fear that he might drop his victim, we kept at a safe distance behind him, yet within rifle range, and near enough to make a prompt attack when he should settle on the ground. At length we reached the other side of the valley, and found to our intense satisfaction that the monster was making for a rocky ledge on the shoulder of an extinct volcano, where we could see the yawning mouth of what appeared an immense cavern. "That is probably his den," said Gazen, who was now as collected as I have ever seen him. Nevertheless all his faculties were on the stretch. His keen grey eye was everywhere, and his active mind was calculating every chance. I felt then as I had often felt before that in action as well as in thought the professor was a man of no common mark. The event showed that his surmise was correct, for soon after he had spoken the dragon uttered a startling cry--a kind of squawk like that of a drake, but much louder, hoarser, shriller--and alighted on the ground. "There is not a moment to lose," said Gazen. "We must attack him before he enters the cave."