“You’re mistaken there, Bob, and I’ll prove it some day,” I answered pleasantly, and then I left him.

My curiosity was roused regarding Brettle, and I took the trouble to have him watched, when I discovered that he really was trying to get work, and even undertaking the meanest drudgery to earn a living. Everything was against him, of course, and he went back steadily till his clothes would scarcely allow him to appear on the street.

In making these investigations I was continually contrasting Brettle’s condition and evident inclinations with Dirty Dick’s prophecy, that I should soon have the ticket-of-leave man in my hands again, and with no success so far as a solution is concerned. The promised “tip” had never come, and even Dick was a mystery to me. I was at a loss to know whence came the money which Dick spent so freely upon himself. He did not work; he was too cowardly to engage in any act of plundering likely to produce much gain; and yet he had abundance, while Brettle was in great want. Dick had the reputation of being able to arrange a robbery very nicely, but would never risk his own liberty in the affair, however tempting the gain; but even knowing that to be a source of income to him, I was at a loss to account for his seeming wealth. Thus it chanced that my attention came to be more earnestly fixed upon Dick than upon the man he had promised to betray into my hands. When I saw Dick moving in a stealthy and cat-like way before me, one day when I was passing along Princes Street, and knew that he was quite unconscious of my presence, I was quickly roused to an interest in his movements. I had not watched him long, when I thought the solution of the whole mystery was in my hands. It seemed to me that Dick’s new line was pocket-picking, and that he was following a likely plant—an elderly gentleman and a lady—with the intention of exercising his new art. After a time it dawned upon me that Dick’s cowardice was against him. Several chances occurred which he did not attempt to make use of. At length the gentleman went into one of the shops alone, and then, to my surprise, the lady, who had remained standing at the window, turned slightly, noticed Dick standing near, moved a little closer to him, and addressed some words to him in a hurried and constrained manner, which Dick as swiftly answered. The lady then took out her purse, and, placing a coin in his hand, turned once more to look in at the window, while Dick passed on with the crowd as if nothing had happened. Now, had Dick been the first to speak, and had the lady’s manner been different, I should have considered it an ordinary case of begging, and had no scruple in following and taking Dick. But as it was I could only wonder what connection such a haughty and evidently wealthy person could have with a miserable coward like him. Instead of following Dick I followed the lady as soon as she had been rejoined by the white-haired gentleman, whom I took to be her husband. From the side glimpse which I had of her face she seemed to be quite young and very good-looking, though there was a nameless something in the expression of her face which told me that she had not always been in such a position. In order to get a better look at her, I got past the couple on the opposite side of the street, crossed over while they stood inspecting a window, and then, as soon as they moved, sauntered slowly forward and met them full in the face. Purposely I got directly in front of the lady, in seeming forgetfulness, and, as she stopped in haughty surprise, I had a good look into her eyes. Then I started and looked again, upon which her glance fell before mine as surely as those of one of “my bairns” ever did. In a moment more she was past, and I was left wondering. I was puzzled and bewildered. The face seemed strangely familiar to me; I could have sworn that I had known the owner of it long before, and yet I could not tell her name or recall a single circumstance in her history. I stood there cudgelling my brains till I had almost lost sight of the couple who had so interested me; then, unable to make a better of it, I roused myself and followed them for a full hour, till they entered one of the biggest hotels in the city and remained there. A waiter running out a moment or two after, on being stopped by me, said that the couple were “Mr and Mrs Harper, from Glasgow,” and that he understood that the gentleman was very wealthy. They were in Edinburgh on a pleasure trip, and, so far as he knew, had no children.

That was all I could get from the waiter, but the news did not banish that beautiful face—so full of sweetness and innocence, if a certain flash could have been taken from her fine eyes. That flash was the only thing to turn the scales, and it did that most effectually. It gave just such an expression to the whole face as I could imagine Lucrezia Borgia to have owned.

Later in the day, when thinking of Brettle and his affairs, by some queer turn of memory I recalled the name of Pretty Polly, and then her sweet-looking features rose before me as vividly as if I had seen them only the day before. But that was not all; for lo! as I looked, the fine features became somewhat stouter and coarser, and rapidly changed into those of Mrs Harper, whom I had that day followed along Princes Street.

“How like they are to each other!” was my mental exclamation. “It must have been that resemblance which puzzled me. But could they be the same person? Never! Brettle says Pretty Polly is dead.”

This reasoning did not convince me, for there still remained the curious fact that the haughty Mrs Harper had allowed her glance to fall before my own in that fashion so suggestive to me of “auld acquaintance.” Could Pretty Polly have had a sister who resembled her? I thought not; for had not Brettle himself said, “The like of her doesn’t walk the earth?” Besides, if she had a sister, and she in such a good position, I could scarcely believe that the lady would be so heartless as to allow her brother-in-law to almost perish of want while she revelled in luxury.

I was waited for by Dick at a street corner on the afternoon of the following day. When I saw him I was a little pleased, as I thought it possible that I might get out of him all I wanted in regard to the strange woman. But as Dick was full to the eyes with his own affairs, I let him chatter about them first.

“I can give you the straight tip about Brettle at last,” he eagerly began.

“Do you expect me to pay you for it?” I quietly interposed.