at hand a strange sound between a snort and a hiss; and turning instinctively to the quarter from which it came, I saw emerging from a dark fissure in the rock a vast and terrible head, with open jaws and dull, ghastly, hungry eyes—­the head of a monstrous reptile resembling that of the crocodile or alligator, but infinitely larger than the largest creature of that kind I had ever beheld in my travels.  I started to my feet and fled down the valley at my utmost speed.  I stopped at last, ashamed of my panic and my flight, and returned to the spot on which I had left the body of my friend.  It was gone; doubtless the monster had already drawn it into its den and devoured it.  The rope and the grappling-hooks still lay where they had fallen, but they afforded me no chance of return; it was impossible to re-attach them to the rock above, and the sides of the rock were too sheer and smooth for human steps to clamber.  I was alone in this strange world, amidst the bowels of the earth.

Chapter III.

Slowly and cautiously I went my solitary way down the lamplit road and towards the large building I have described.  The road itself seemed like a great Alpine pass, skirting rocky mountains of which the one through whose chasm I had descended formed a link.  Deep below to the left lay a vast valley, which presented to my astonished eye the unmistakeable evidences of art and culture.  There were fields covered with a strange vegetation, similar to none I have seen above the earth; the colour of it not green, but rather of a dull and leaden hue or of a golden red.

There were lakes and rivulets which seemed to have been curved into artificial banks; some of pure water, others that shone like pools of naphtha.  At my right hand, ravines and defiles opened amidst the rocks, with passes between, evidently constructed by art, and bordered by trees resembling, for the most part, gigantic ferns, with exquisite varieties of feathery foliage, and stems like those of the palm-tree.  Others were more like the cane-plant, but taller, bearing large clusters of flowers.  Others, again, had the form of enormous fungi, with short thick stems supporting a wide dome-like roof, from which either rose or drooped long slender branches.  The whole scene behind, before, and beside me far as the eye could reach, was brilliant with innumerable lamps.  The world without a sun was bright and warm as an Italian landscape at noon, but the air less oppressive, the heat softer.  Nor was the scene before me void of signs of habitation.  I could distinguish at a distance, whether on the banks of the lake or rivulet, or half-way upon eminences, embedded amidst the vegetation, buildings that must surely be the homes of men.  I could even discover, though far off, forms that appeared to me human moving amidst the landscape.  As I paused to gaze, I saw to the right, gliding quickly through the air, what appeared a small boat, impelled by sails shaped like wings.  It soon passed out of sight, descending amidst the shades of a forest.  Right above me there was no sky, but only a cavernous roof.  This roof grew higher and higher at the distance of the landscapes beyond, till it became imperceptible, as an atmosphere of haze formed itself beneath.