She received this with a low sound of laughter that scarcely rose to her lips. "You are princely. But, my dear sir, does it not occur to you that I may, meanwhile, have taken my own way of repaying myself for any service I have been fortunate enough to render you?"
Durham, at the question, or still more, perhaps, at the tone in which it was put, felt, through his compunction, a vague faint chill of apprehension. Was she threatening him or only mocking him? Or was this barbed swiftness of retort only the wounded creature's way of defending the privacy of her own pain? He looked at her again, and read his answer in the last conjecture.
"I don't know how you can have repaid yourself for anything so disinterested—but I am sure, at least, that you have given me no chance of recognizing, ever so slightly, what you have done."
She shook her head, with the flicker of a smile on her melancholy lips. "Don't be too sure! You have given me a chance and I have taken it—taken it to the full. So fully," she continued, keeping her eyes fixed on his, "that if I were to accept any farther service you might choose to offer, I should simply be robbing you—robbing you shamelessly." She paused, and added in an undefinable voice: "I was entitled, wasn't I, to take something in return for the service I had the happiness of doing you?"
Durham could not tell whether the irony of her tone was self-directed or addressed to himself—perhaps it comprehended them both. At any rate, he chose to overlook his own share in it in replying earnestly: "So much so, that I can't see how you can have left me nothing to add to what you say you have taken."
"Ah, but you don't know what that is!" She continued to smile, elusively, ambiguously. "And what's more, you wouldn't believe me if I told you."
"How do you know?" he rejoined.
"You didn't believe me once before; and this is so much more incredible."
He took the taunt full in the face. "I shall go away unhappy unless you tell me—but then perhaps I have deserved to," he confessed.
She shook her head again, advancing toward the door with the evident intention of bringing their conference to a close; but on the threshold she paused to launch her reply.