The man gave his interrupter a spiteful glance. "Well, sir," he said, "as you gave me strict instructions to watch a certain gentleman closely, I obeyed those instructions, of course, although I knew I was on a fool's errand." "Will you go on?" cried Carriston. "If you know where Miss Rowan is, say so; your money will be paid you the moment I find her." "I don't say I exactly know where to find the lady, but I can soon know if you wish me to." "Tell your tale your own way, but as shortly as possible," I said, seeing that my excitable friend was preparing for another outburst. "I found there was nothing to be gained by keeping watch on the gentleman you mentioned, sir, so I went to Scotland and tried back from there. As soon as I worked on my own lay I found out all about it. The lady went from Callendar to Edinburgh, from Edinburgh to London, from London to Folkestone, and from Folkestone to Boulong." I glanced at Carriston. All his calmness seemed to have returned. He was leaning against the mantelpiece, and appeared quite unmoved by Mr. Sharpe's clear statement as to the route Madeline had taken. "Of course," continued Mr. Sharpe, "I was not quite certain I was tracking the right person, although her description corresponded with the likeness you gave me. But as you are sure this article of jewelry belonged to the lady you want, the matter is beyond a doubt." "Of course," I said, seeing that Carriston had no intention of speaking. "Where did you find it?" "It was left behind, in a bedroom of one of the principal hotels in Folkestone. I did go over to Boulong, but after that I thought I had learned all you would care to know." There was something in the man's manner which made me dread what was coming. Again I looked at Carriston. His lips were curved with contempt, but he still kept silence. "Why not have pursued your inquiries past Boulong?" I asked. "For this reason, sir. I had learned enough. The theory I had concocted was the right one after all. The lady went to Edinburgh alone, right enough: but she didn't leave Edinburgh alone, nor she didn't leave London alone, nor she didn't stay at Folkestone--where I found the pin--alone, nor she didn't go to Boulong alone. She was accompanied by a young gentleman who called himself Mr. Smith; and what's more, she called herself Mrs. Smith. Perhaps she was; as they lived like man and wife."