Helen grew as pale as she had been rosy, and her face as the moonlight fell upon it was very sorrowful.

“He stayed with us in Scotland two summers ago,” she said softly.  “He was very agreeable...”

“Ha!  No doubt!  He made a sort of love to you then, I suppose.  I can imagine him doing it very well!  There is a nice romantic glen near your house—­just where the river runs, and where I caught a fifteen-pound salmon some five years ago.  Ha!  Catching salmon is healthy work; much better than falling in love.  No, no, Helen!  Gervase is not good enough for you; you want a far better man.  Has he spoken to you to-night?”

“Oh, yes!  And he has danced with me.”

“Ha!  How often?”

“Once.”

“And how many times with the Princess Ziska?”

Helen’s fair head drooped, and she answered nothing.  All at once the little Doctor’s hand closed on her arm with a soft yet firm grip.

“Look!” he whispered.

She raised her eyes and saw two figures step out on the terrace and stand in the full moonlight,—­the white Bedouin dress of the one and the glittering golden robe of the other made them easily recognizable,—­they were Gervase and the Princess Ziska.  Helen gave a faint, quick sigh.

“Let us go in,” she said.

“Nonsense!  Why should we go in?  On the contrary, let us join them.”

“Oh, no!” and Helen shrank visibly at the very idea.  “I cannot; do not ask me!  I have tried—­you know I have tried—­to like the Princess; but something in her—­I don’t know what it is—­repels me.  To speak truthfully, I think I am afraid of her.”

“Afraid!  Pooh!  Why should you be afraid?  It is true one doesn’t often see a woman with the eyes of a vampire-bat; but there is nothing to be frightened about.  I have dissected the eyes of a vampire-bat—­very interesting work, very.  The Princess has them—­ only, of course, hers are larger and finer; but there is exactly the same expression in them.  I am fond of study, you know; I am studying her.  What!  Are you determined to run away?”

“I am engaged for this dance to Mr. Courtney,” said Helen, nervously.

“Well, well!  We’ll resume our conversation another time,” and Dr. Dean took her hand and patted it pleasantly.  “Don’t fret yourself about Denzil; he’ll be all right.  And take my advice:  don’t marry a Bedouin chief; marry an honest, straightforward, tender-hearted Englishman who’ll take care of you, not a nondescript savage who’ll desert you!”

And with a humorous and kindly smile, Dr. Dean moved off to join the two motionless and picturesque figures that stood side by side looking at the moon, while Helen, like a frightened bird suddenly released, fled precipitately back to the ball-room, where Ross Courtney was already searching for her as his partner in the next waltz.

“Upon my word,” mused the Doctor, “this is a very pretty kettle of fish!  The Gezireh Palace Hotel is not a hotel at all, it seems to me; it is a lunatic asylum.  What with Lady Fulkeward getting herself up as twenty at the age of sixty; and Muriel and Dolly Chetwynd Lyle man-hunting with more ferocity than sportsmen hunt tigers; Helen in love, Denzil in love, Gervase in love—­dear me! dear me!  What a list of subjects for a student’s consideration!  And the Princess Ziska ...”