At four o'clock in the afternoon I had heard nothing further from Bristol, but I did not doubt that he would advise me of his arrangements in good time. I sought by hard work to forget for a time the extraordinary business of the stolen slipper; but it persistently intruded upon my mind. Particularly, my thoughts turned to the night of Professor Deeping's murder, and to the bewitchingly pretty woman who had warned me of the impending tragedy. She had bound me to secrecy—a secrecy which had proved irksome, for it had since appeared to me that she must have been an accomplice of Hassan of Aleppo. At the time I had been at a loss to define her peculiar accent, now it seemed evidently enough to have been Oriental.
 
I threw down my pen in despair, for work was impossible, went downstairs, and walked out under the arch into Fleet Street. Quite mechanically I turned to the left, and, still engaged with idle conjectures, strolled along westward.
 
Passing the entrance to one of the big hotels, I was abruptly recalled to the realities—by a woman's voice.
 
"Wait for me here," came musically to my ears.
 
I stopped, and turned. A woman who had just quitted a taxi-cab was entering the hotel. The day was hot and thunderously oppressive, and this woman with the musical voice wore a delicate costume of flimsiest white. A few steps upward she paused and glanced back. I had a view of a Greek profile, and for one magnetic instant looked into eyes of the deepest and most wonderful violet.
 
Then, shaking off inaction, I ran up the steps and overtook the lady in white as a porter swung open the door to admit her. We entered together.
 
"Madame," I said in a low tone, "I must detain you for a moment. There is something I have to ask."
 
She turned, exhibiting the most perfect composure, lowered her lashes and raised them again, the gaze of the violet eyes sweeping me from head to foot with a sort of frigid scorn.
 
"I fear you have made a mistake, sir. We have never met before!"
 
Her voice betrayed no trace of any foreign accent!
 
"But," I began—and paused.
 
I felt myself flush; for this encounter in the foyer of an hotel, with many curious onlookers, was like to prove embarrassing if my beautiful acquaintance persisted in her attitude. I fully realized what construction would be put upon my presence there, and foresaw that forcible and ignominious ejection must be my lot if I failed to establish my right to address her.
 
She turned away, and crossed in the direction of the staircase. A sunbeam sought out a lock of hair that strayed across her brow, and kissed it to a sudden glow like that which lurks in the heart of a blush rose.
 
That wonderful sheen, which I had never met with elsewhere in nature, but which no artifice could lend, served to remove my last frail doubt which had survived the evidence of the violet eyes. I had been deceived by no strange resemblance; this was indeed the woman who had been the harbinger of Professor Deeping's death. In three strides I was beside her again. Curious glances were set upon me, and I saw a servant evidently contemplating approach; but I ignored all save my own fixed purpose.
 
"You must listen to what I have to say!" I whispered. "If you decline, I shall have no alternative but to call in the detective who holds a warrant for your arrest!"
 
She stood quite still, watching me coolly. "I suppose you would wish to avoid a scene?" I added.
 
"You have already made me the object of much undesirable attention," she replied scornfully. "I do not need your assurance that you would disgrace me utterly! You are talking nonsense, as you must be aware—unless you are insane. But if your object be to force your acquaintance upon me, your methods are novel, and, under the circumstances, effective. Come, sir, you may talk to me—for three minutes!"
 
The musical voice had lost nothing of its imperiousness, but for one instant the lips parted, affording a fleeting glimpse of pearl beyond the c............