Lady Claire looked up quickly.  Her voice showed her struck with sudden surprise.  “You are going—­so soon?”

“To-morrow.”

“To Assouan?” Odd sharpness edged the question.

He waited a perceptible moment, though his resolution had been taken.  “Back to Cairo.”

“Oh ...  How long shall you be there?”

“Just till I get sailings.  It’s time for me to be off.  I’m really a working person, you know, not a playing one.”

“You make bridges—­and dams—­and things, don’t you?” she questioned vaguely.

“Bridges—­and dams—­and things.”

“Why don’t you wait here for your sailings?” she asked impersonally after another pause.  “It’s so much more attractive here than Cairo.”

“I’d like to.”  He thought of next Friday—­and Arlee’s return—­and the masked ball.  For a moment temptation urged.  Then he threw back his head with a gesture of decision.  “But I can’t.  It’s impossible.”

Now Lady Claire did not know that he was thinking of next Friday—­and Arlee’s return—­and the masked ball.  She only knew that he spoke with a curious fierceness, and that his eyes were very bright.  And something in the girl, something strange and acknowledged that had been so fitfully gay and light these three days, quickened in mysterious excitement.

“Nothing is impossible,” she gave back, “to a man!”

Billy thought she was resenting the conventions of the restricted sex.  She could not make any open advance toward Falconer while he, as man, could make all the open advances to Arlee he was willing to—­but in this case his hands were tied.  A man cannot inflict himself upon a girl who may not feel herself free to reject him.  He laughed, with sorry ruefulness.

“There’s a whole lot,” he observed, “that is impossible to a man who tries to be one,” and then, oblivious of any construction she might choose to put upon this cryptic utterance, he strolled moodily on, in brooding silence.

After a pause, “Of course,” said Lady Claire in so gentle a little voice that it seemed to glide undisturbingly among his silent meditations, “of course, a man has his—­pride.”

“I hope so,” said the young man briefly.  He understood her to be probing for his reason for abandoning the chase; he understood that for her own sake she would like to see him successful with Arlee, and he was queerly sorry to be failing to help her there.  But he had done all that he could....

The girl spoke again, her face straight ahead, her shadowy eyes staring out into the moonlight.  “Is it—­money?” she said in the same little breath of a voice.