“Why, Miss Bristowe!” I cried. “Perhaps you don’t recollect me?”

She started quickly, and drew back for a moment, her countenance blanching; then looking into my face, she said, with a timid laugh: “Why, of course, doctor! But have you forgiven me for taking you on that fool’s errand?”

“Yes, long ago,” I laughed. “But our meeting this evening is certainly unexpected. Have you friends in this neighbourhood?”

She replied in the affirmative, but without giving me any explanation.

“And your brother?” I asked, recollecting Whitworth’s declaration that he had never heard of her. “Is he any better?”

“Oh, a great deal, thanks,” was her reply. “He took a turn for the better that night I came to you, and has improved ever since.”

She looked, I think, prettier than on that night when we had driven together to Blackheath. But she had deceived me in regard to her statement concerning Dr. Whitworth, so I supposed she was deceiving me now.

She was in a hurry to get home, she told me, and my first impulse was to follow her secretly, but when I recollected that the man for whom I had been so long in wait was actually inside No. 7, I decided to keep watch upon him rather than upon her.

The fact that she had come from that house was in itself curious, and made me suspect that her visit to me on that night in Walworth had some secret connection with the scheme of this man Purvis.

The manner in which she was hurrying when I stopped her made it plain that she was late for some appointment.

There were two courses open to me, namely: to follow her, or else to remain and await Purvis. The discovery that she was friendly with some person at No. 7 had suddenly aroused within me a desire to know her place of abode in order to make secret inquiries concerning her. Yet, after all, my chief business was with Purvis, so I decided to remain on watch for him.

With her consent, therefore, I saw her into an omnibus for Ludgate Hill, whence she told me she would take train home, and when I parted from her I expressed a fervent hope that we might meet again before very long.

“Good-night,” she said, as we shook hands. “Yes, I hope we shall meet again—in more fortunate circumstances than to-night.” And she mounted into the omnibus and left me.

What could she mean by more fortunate circumstances? I was puzzled at her words, but at last their truth became apparent.

Through many hours, till far into the night, I waited in that vicinity for the man who was my rival. But he never came out, neither that day nor the next.

The reason, I afterwards found, was simple enough. The servant had played me false and told him everything; therefore he had waited until darkness set in, and then climbed over several garden walls into Wells Street, a short thoroughfare running parallel at the back, and quietly emerged into Gray’s Inn Road.

So while I had waited patiently in front he had ingeniously escaped at the back, aided most probably by the mysterious Miss Bristowe and Mrs. Graham, whose character, of course, I had no means of ascertaining. According, however, to my friend the constable, some shifty individuals lived in that neighbourhood.

In any case I had the dissatisfaction of knowing that all my vigilance had been naught, and that the man Purvis would never again run the gauntlet of Calthorpe Street. He would no doubt arrange for another address, and if so I might obtain it by means of the Kenways, providing, of course, that they had not yet told him the house was let.

I took counsel with Mr. Staffurth, as I did very frequently nowadays.

I blamed myself that on that night I was alone. Had I an assistant with me he might have followed the young lady home. Staffurth being of the same opinion, suggested that I should accept the services of his nephew, a young bank clerk who had been compelled to leave his occupation in the City temporarily on account of ill-health. This young fellow, whom I had met once or twice at Clapham, was named Philip Reilly. Smart, well dressed, and well educated, he had been an athlete before his illness, and had carried off many prizes at Lillie Bridge and other places.

He was just the sort of young man to be useful, and when that evening he sat in his uncle’s study and the full facts of the case were related to him in confidence, he became highly excited over it, and announced his eagerness to act under my directions.

“We have a formidable enemy to contend with, Philip,” the old gentleman pointed out. “And recollect that whatever may happen you must act with due caution so as not to play into the hands of our rivals.”

“Trust me for that,” he said. “The affair sounds exciting, at all events.”

“Yes,” I remarked, “and matters will grow more exciting before long, I anticipate.”

“But this Miss Bristowe,” he exclaimed. “Have we no means of rediscovering her?”

“At present, I am sorry to say, we haven’t,” I responded. “We may possibly get hold of Purvis’s new postal address, and if we do so it may lead us back to Miss Bristowe, who seems to me somehow associated with him. How, of course, I can’t tell.”

Reilly sat with folded arms, his clean-shaven face bearing a deep, thoughtful look as he puffed his pipe. It is not given to every one to be engaged on a treasure hunt, and from the first moment when he was told about it its interest overwhelmed him and he was eager to make a commencement.

After a long consultation it was arranged that we should both go down to Caldecott and endeavour to find out Purvis’s new address. It was also agreed that before we took another step we ought to be acquainted with the personal appearance of our rival.

To work in the dark any longer might, we foresaw, prove fatal to our object; therefore, on the following day, I introduced Reilly to the Kenways as the new tenant of the Manor House.

Fortunately they had not communicated with Purvis. Hence I took them somewhat into............