“It was the ring,” she cried, handing it to him.

Kennedy took the ring and looked at it for a moment.  Then he turned to us blankly.

All the rooms were empty.

Elaine had been spirited away.

CHAPTER III

THE WATCHING EYE

Not a clue was left by the kidnappers when they so mysteriously spirited Elaine away from the apartment of Wu Fang.  She had disappeared as completely as if she had vanished into the thin air.

Kennedy was frantic.  Wu and Long Sin themselves seemed to have vanished, too.  Where they held her, what had happened to her was a sealed book.  And yet, no move of ours was made, no matter how secret, that it did not seem to be known to them.  It was as though a weird, uncanny eye glared at us, watching everything.

Craig neglected no possibility in his eager search.  He even visited the little house in the country which Elaine had given to Aunt Tabby, and spent several hours examining the collapsed subterranean chamber in the vain hope that it might yield a clue.  But it had not.

It was half filled with debris from above, where the pillar had given way that night when we had all so nearly lost our lives.  Still, there was enough room in what remained of the cavern so that we could move about.

Kennedy had even dug away some of the earth and rock, in the hope of discovering some trace of the strange visitor whom we had surprised at work.  But here, also, he had found nothing.

It was maddening.  What might at any moment be happening to Elaine--and he powerless to help her?

Unescapably, he was forced to the conclusion that not only Elaine’s amazing disappearance, but the tragic succession of events which had preceded it, had been caused, in some way, by the curiously engraved ring which Aunt Josephine had taken from Elaine.

Craig had taken possession of the mystic ring himself, and now, forced back on this sole clue, it had occurred to him that if the ring were so valuable, other attempts would, without doubt, be made to get possession of it.

I came into the laboratory, one afternoon, to find Kennedy surrounded by jeweler’s tools, hard at work making an exact copy of the ring.

“What do you think of it, Walter?” he asked, holding up the replica.

“Perfect,” I replied, admiringly.  “What are you going to do with it?”

“I can’t say—­yet,” answered Kennedy, forlornly, “but if I understand these Chinese criminals at all, I know that the only way we can ever track them is through some trick.  Perhaps the replica will suggest something to us later.”

He placed the copy in a velvet-lined box closely resembling that in which the real ring lay, and dropped both into his pocket.

“Let’s see if Aunt Josephine has received any word,” he remarked abruptly, putting on his hat and coat, and nodding to me to follow.