As they were talking they had rounded a sudden bend in the defile, and the salute he had jocosely directed to the dead Syyed--if such a person had ever existed in fact--had been caught up by a most astounding echo, which, for no apparent reason, was given forth precisely at that spot. Still, it was not a little curious that they should have entered within its scope simultaneously with the utterance of the half-mocking words, which, mingling with the rattle of the horses' hoofs upon the loose stones of the _tangi_, had produced the horrible din. Now it was she who said in a whisper,-- "We had better not talk out loud or these horses will go quite mad. It is all I can do to stay on mine as it is." In fact the animals were in the wildest stage of snorting, trembling fear, and could hardly be persuaded to proceed at all. Their shying and plunging created a rattle which the echo reproduced and magnified as before. At length they quieted down. "We may be through the sphere of the echo," said Raynier, tentatively raising his voice a little. And the result showed that they were. "How is it the same thing did not happen when you came through here before?" said Hilda Clive, as soon as it became safe to converse again. "Easily explained. I left my horse at the entrance and walked. I always wear very silent boots, and I had nobody to talk to. Look, we are through now, but we sha'n't have much time to admire the view on the other side because it's rather late, and we ought to get back to camp." A tower of light now rose in front of them, light only in comparison to the gloom of the _tangi_. It was the exit at the other end, similar in every particular to the entrance. They stood looking out over a wild wide valley shut in by the same eternal hills. From far beneath among the gloomy rifts and sparse vegetation arose the long-drawn howl of a wolf. "What a wilderness!" exclaimed the girl. "Do you know, it's splendid. I'm so glad I came." She had turned her eyes full upon his face. What wonderful eyes they were, he thought--and they were fascinating too. How on earth had he been so long in making the discovery? He thought, too, how she had been the one whose nerves had remained entirely unshaken during that very startling surprise--how she it was--not he--who had at once seen through its perfectly natural solution, and he felt small accordingly. But his admiration for her had strangely increased. They turned to retrace their way, hardly able to make it out in the gloom. They had been descending all the time, and now it took a little longer, for the floor of the _tangi_ was stony and rough. "I'm not surprised they have set up a ghost here," said Raynier, when they had passed the echo point. "That is one of the most extraordinary effects I have ever experienced."