But it ended at last. The machine stopped, Helen knew not where, and she was assisted out by the two men, who led her, still blindfolded, along a fairly smooth trail, up the side of a mountain or steep hill, then along a fairly level stretch, until at last the prisoner knew that she was passing under a canopy or roof of some sort, for there was no snow under foot. Moreover their footfalls produced a sound, somewhat of the nature of a soft resonant reverberation of a million tiny echoes.