The English horses drew them swift as the wind. It seemed but a short half-hour ere they stopped at a gate opening into a wood, shadowy, dark, and dreadful, after the dusty road and level meadows glistening silver-white in the moonlight. The two Musketeers, accustomed to look about them, perceived at their feet a track of wheels, which had obviously preceded their carriage. Bras-de-Fer felt a little disappointed. “_L’affaire commence!_” whispered the Regent, loosening his sword, as he prepared to follow Bartoletti through the wood. “Keep close to me, gentlemen, and look that we be not taken in rear!” The path was narrow, winding, and exceedingly dark; but after a furlong or two the party emerged on an open space, and found their progress stopped by a level wall of rock, hewn perfectly smooth, and several yards in height. Bathed in a strong moonlight, every particle on its gritty surface glistened like crystal, and its crest of stunted trees and thick-growing shrubs cut clear and black against the cloudless sky. Here the adept halted and looked round. “Highness,” he whispered, “we have reached our journey’s end; have you courage to enter the cave?” The Duke’s face was pale, but he glanced at his two Musketeers, and answered, “After you, monsieur!” Then the four, in Indian file, turned through an opening, or rather a mere hole in the rock, to follow a low, narrow passage, in which, ere they had advanced three paces, the darkness became impenetrable. They groped their way in silence, each listening to the hard breathing of his predecessor. Bras-de-Fer, who was last, fervently hoping their ghostly enemy might not attack them until, as he would have expressed it, they could “deploy into line.” The corridor, however, as we may call it, grew wider and loftier at every step. Presently they marched upright, and two abreast. There was a constant drip from the damp stone that encircled them, and the hard smooth surface on which they trod felt cool and refreshing to their feet. Bras-de-Fer could not restrain a sneeze. It resounded above their heads, and died away farther and fainter in a hundred whispering echoes. Bartoletti started violently, and the Duke’s hand went to his sword. Then the magician halted, pulled a vial from his breast, and dipping a match in it, produced a strong rose-coloured flame, from which he lit the small lamp that hung at his belt. Whilst the match flared and shone, they saw plainly for several yards in every direction. They were in a low vaulted cavern, hewn, to all appearance, by no mortal hands, out of the rock. They stood on a slightly-elevated platform, and at their feet lay a glistening sheet of black that could only be water. It was, however, a hasty examination, for the match soon spent itself, and Bartoletti’s lamp gave but light enough, as Bras-de-Fer observed, “to show how dark it was.” “Are we on the banks of the Seine or the Styx?” asked the Regent, jestingly, yet with a slight tremor in his voice.