And with her sombre eyes darkening, yet glowing with the inward fire that always smouldered in their dazzling depths, she saluted him gravely and gracefully, watching him to the last as he slowly withdrew.

CHAPTER XV.

The next day broke with a bright, hot glare over the wide desert, and the sky in its cloudless burning blue had more than its usual appearance of limitless and awful immensity.  The Sphinx and the Pyramids alone gave a shadow and a substance to the dazzling and transparent air,—­all the rest of the visible landscape seemed naught save a far-stretching ocean of glittering sand, scorched by the blazing sun.  Dr. Maxwell Dean rose early and went down to the hotel breakfast in a somewhat depressed frame of mind; he had slept badly, and his dreams had been unpleasant, when not actually ghastly, and he was considerably relieved, though he could not have told why, when he saw his young friend Denzil Murray, seated at the breakfast table, apparently enjoying an excellent meal.

“Hullo, Denzil!” he exclaimed cheerily, “I hardly expected you down yet.  Are you better?”

“Thanks, I am perfectly well,” said Denzil, with a careless air.  “I thought I would breakfast early in order to drive into Cairo before the day gets too sultry.”

“Into Cairo!” echoed the Doctor.  “Why, aren’t you going to stay here a few days?”

“No, not exactly,” answered Denzil, stirring his coffee quickly and beginning to swallow it in large gulps.  “I shall be back to-night, though.  I’m only going just to see my sister and tell her to prepare for our journey home.  I shan’t be absent more than a few hours.”

“I thought you might possibly like to go a little further up the Nile?” suggested the Doctor.

“Oh, no, I’ve had enough of it!  You see, when a man proposes to a woman and gets refused, he can’t keep on dangling round that woman as if he thought it possible she might change her mind.”  And he forced a smile.  “I’ve got an appointment with Gervase to-morrow morning, and I must come back to-night in order to keep it—­but after that I’m off.”

“An appointment with Gervase?” repeated the Doctor, slowly.  “What sort of an appointment?”

Denzil avoided his keen look.

“Really, Doctor, you are getting awfully inquisitive!” he exclaimed with a hard laugh.  “You want to know altogether too much!”

“Yes, I always do; it is a habit of mine,” responded Dr. Dean, calmly.  “But in the present case, it doesn’t need much perspicuity to fathom your mystery.  The dullest clod-hopper will tell you he can see through a millstone when there’s a hole in it.  And I was always a good hand at putting two and two together and making four out of them.  You and Gervase are in love with the same woman; the woman has rejected you and is encouraging Gervase; Gervase, you think, will on this very night be in the position of the accepted lover, for which successful fortune, attending him, you, the rejected one, propose to kill him to-morrow morning if you can, unless he kills you.  And you are going to Cairo to get your pistols or whatever weapons you have arranged to fight with, and also to say good-bye to your sister.”