A voice whose prompting he could not resist, impelled Tristan, after his parting from the Monk of Cluny, to follow the Grand Chamberlain, who had taken the direction of the Pincian Hill. His retreating form became more phantom-like in the misty moonlight, as viewed from the ramparts of the Emperor's Tomb. Nevertheless, mindful of the parting words of the monk, and filled with dire misgivings, Tristan set out at once. True to his determination, he procured a small lantern and a piece of coarse thick cloth, which he concealed under his cloak, then, by a solitary pathway, he followed the direction he had seen Basil take. The Bridge of San Angelo was deserted and not a human being was abroad. After a time he arrived at a small copse, where Basil's form had disappeared from sight. Clearing away the underbrush, Tristan came to what seemed a fissure in a wall, which cast a tremendous shadow over the surrounding trees and bushes. Creeping in as far as he dared, he paused, then, with mingled emotions of expectancy and apprehension which affected him so powerfully that for a moment he was hardly master of his actions, he slowly and carefully uncovered his lantern, struck two flints and lighted the wick. His first glance was intuitively directed to the cavity that opened beneath him. Of Basil he saw no trace, notwithstanding he had seen him enter the cavity at the point where he himself had entered. Ere long however, he heard a thin, long-drawn sound, now louder, now softer; now approaching, now receding, now verging toward shrillness, now returning to a faint, gentle swell. This strange, unearthly music was interrupted by a succession of long, deep rolling sounds, which rose grandly about the fissures above, like prisoned thunderbolts striving to escape. Roused by the mystery of the place and the uncertainty of his own purpose, Tristan was, for a moment, roused to a pitch of such excitement that almost threatened to unsteady his reason. Conscious of the danger attending his venture, and the fearful legends of invisible beings and worlds, he was constrained to believe that demons were hovering around him in viewless assemblies, calling to him in unearthly voices, in an unknown tongue, to proceed upon his enterprise and take the consequences of his daring. Thus he remained for a time, fearful of advancing or retracing his steps, looking fixedly into the trackless gloom and listening to the strange sounds which, alternately rising and falling, still floated around him. The fitful light of his lantern suddenly fell upon a shape that seemed to creep through one of the stone galleries. In the unsteady gleam it appeared from the distance like a gnome wandering through the bowels of the earth, or a forsaken spirit from purgatory. Had it been but a trick of his imagination, or had his mortal eyes seen a denizen of the beyond? At last he aroused himself, trimmed with careful hand his guiding wick and set forth to penetrate the great rift.