"I had some very narrow escapes at first, but I have gradually learned to go about. There is a certain system to it, but it is one which a lost man, if he were in the dark, could not possibly find out. Even now I always spin out a ball of string behind me when I am going far into the catacomb. You can see for yourself that it is difficult, but every one of these passages divides and subdivides a dozen times before you go a hundred yards." They had descended some twenty feet from the level of the byre, and they were standing now in a square chamber cut out of the soft tufa. The lantern cast a flickering light, bright below and dim above, over the cracked brown walls. In every direction were the black openings of passages which radiated from this common centre. "I want you to follow me closely, my friend," said Burger. "Do not loiter to look at anything upon the way, for the place to which I will take you contains all that you can see, and more. It will save time for us to go there direct." He led the way down one of the corridors, and the Englishman followed closely at his heels. Every now and then the passage bifurcated, but Burger was evidently following some secret marks of his own, for he neither stopped nor hesitated. Everywhere along the walls, packed like the berths upon an emigrant ship, lay the Christians of old Rome. The yellow light flickered over the shrivelled features of the mummies, and gleamed upon rounded skulls and long, white armbones crossed over fleshless chests. And everywhere as he passed Kennedy looked with wistful eyes upon inscriptions, funeral vessels, pictures, vestments, utensils, all lying as pious hands had placed them so many centuries ago. It was apparent to him, even in those hurried, passing glances, that this was the earliest and finest of the catacombs, containing such a storehouse of Roman remains as had never before come at one time under the observation of the student. "What would happen if the light went out?" he asked, as they hurried onwards. "I have a spare candle and a box of matches in my pocket. By the way, Kennedy, have you any matches?" "No; you had better give me some." "Oh, that is all right. There is no chance of our separating." "How far are we going? It seems to me that we have walked at least a quarter of a mile." "More than that, I think. There is really no limit to the tombs--at least, I have never been able to find any. This is a very difficult place, so I think that I will use our ball of string." He fastened one end of it to a projecting stone and he carried the coil in the breast of his coat, paying it out as he advanced. Kennedy saw that it was no unnecessary precaution, for the passages had become more complex and tortuous than ever, with a perfect network of intersecting corridors. But these all ended in one large circular hall with a square pedestal of tufa topped with a slab of marble at one end of it.