“An extremely ingenious method,” commented the professor, “and one that makes me proud of my brother-in-law, if he were the author.”

“What makes you think that my father was the one who did it?” asked Don.

“My thought would have leaped to him at once because of his brilliancy,” replied Phalos. “But I had something a little more definite than that. I turned over the bit of paper I had in my hand and saw that a name had been scribbled on it. Only a few of the letters remained, but I could make out ‘urdy.’”

“Fairly conclusive,” agreed the captain.

“Later on, when I met Mr. Sturdy,” resumed Phalos, “I could see that he was intensely excited over something. I tried to sound him out casually, but he evaded me. I was sure that he had made what he thought was a great discovery.”

“That’s what he must have had in mind when he kept talking to mother about the Tombs of Gold!” exclaimed Don.

“Did he really speak of them?” asked Phalos, much interested. “That goes still further toward confirming my suspicion. The thought that had been with him on and off for years must have taken full possession of him when his mind became deranged, to the exclusion of everything else.”

“That makes it all the more likely,” observed the captain, “that we’ll find him somewhere in the vicinity of the Valley of the Kings, where the inscription was discovered.”

“Precisely so,” agreed the old Egyptian. “However, the search may lead him far afield, for I have reason to believe that the tombs themselves are at some distance from the place where the inscription was found. That inscription was placed there because the towering cliff offered the spot where it was most likely to endure for ages.”

“It was certainly a lucky day for us when we met you on the steamer,” declared Don enthusiastically.