He looked, and sure enough there _was_ an opening, and a dim passage running down through the solid rock. Up he jumped, fired at the prospect of seeing new and wonderful things, and without looking any more to see who had spoken to him, he ran over to it. The passage had a smooth floor of stone, and sloped downward into the earth, and went round and round in an immense spiral; but the circles were so wide that Martin scarcely knew that he was not travelling in a straight line. Have you by chance ever seen a buzzard, or stork, or vulture, or some other great bird, soaring upwards into the sky in wide circles, each circle taking it higher above the earth, until it looked like a mere black speck in the vast blue heavens, and at length disappeared altogether? Just in that way, going round and round in just such wide circles, lightly running all the time, with never a pause to rest, and without feeling in the least tired, Martin went on, only down and down and further down, instead of up and up like the soaring bird, until he was as far under the mountain as ever any buzzard or crane or eagle soared above it. Thus running he came at last out of the passage to an open room or space so wide that, look which way he would, he could see no end to it. The stone roof of this place was held up by huge stone pillars standing scattered about like groups of great rough-barked trees, many times bigger round than hogsheads. Here and there in the roof, or the stone overhead, were immense black caverns which almost frightened him to gaze up at them, they were so vast and black. And no light or sun or moon came down into that deep part of the earth: the light was from big fires, and they were fires of smithies burning all about him, sending up great flames and clouds of black smoke, which rose and floated upwards through those big black caverns in the roof. Crowds of people were gathered around the smithies, all very busy heating metal and hammering on anvils like blacksmiths. Never had he seen so many people, nor ever had he seen such busy men as these, rushing about here and there shouting and colliding with one another, bringing and carrying huge loads in baskets on their backs, and altogether the sight of them, and the racket and the smoke and dust, and the blazing fires, was almost too much for Martin; and for a moment or two he was tempted to turn and run back into the passage through which he had come. But the strangeness of it all kept him there, and then he began to look more closely at the people, for these were the little men that live under the earth, and they were unlike anything he had seen on its surface. They were very stout, strong-looking little men, dressed in coarse dark clothes, covered with dust and grime, and they had dark faces, and long hair, and rough, unkempt beards; they had very long arms and big hands, like baboons, and there was not one among them who looked taller than Martin himself.