The lad was mounting the steps of the hotel. We followed him, and obtained the buff-coloured envelope, addressed to "Richard Carton, Nayland Rock Hotel, Margate," which he delivered to a waiter. Carton tore open the envelope, read the message, and handed it to me. The information it contained was that cheque 134,178, for two thousand pounds, signed by Richard Carton, was cashed across the counter on Saturday morning; that the gentleman who presented it demanded that it should be paid in gold; that as this was a large amount to be so paid the cashier had asked the gentleman to sign his name at the back of the cheque, notwithstanding that it was payable to bearer, and that the signature was that of Kenneth Dowsett. "Do you think there is anything strange in that?" I asked. "It does seem strange," replied Carton thoughtfully. I made a rapid mental calculation, and said, "Two thousand sovereigns in gold weigh forty pounds. A heavy weight for a man to carry away with him." Carton did not reply, but I saw that, for the first time, his suspicions were aroused. "You told me," I continued, "that Mrs. Dowsett and her daughter Letitia went away from their house on Saturday morning early." "So my guardian informed me." "Was any other lady stopping with them?" "I did not understand so from my guardian." "Did they have any particular lady friend whom, for some reason or other, they wished to take with them to the seaside?" "Not to my knowledge." "You can think of no one?" "Indeed, I cannot." "It is your belief that only two ladies left the house?' "Yes, it is my belief." "But," I said, "Mrs. Dowsett took not only her daughter Letitia with her, but another lady, a young lady, as well; and the three, in company with your guardian, left Margate suddenly this morning. I have ascertained this positively. Now, who is this young lady of whom you have no knowledge?" He passed his hand across his forehead, and gazed at me with a dawning terror in his eyes. "Shall I tell you what is in my mind?" "Yes." "If," I said, speaking slowly and impressively, "the theory I have formed is correct--and I believe it is--the young lady is Mary Melladew, poor Lizzie's sister." "Good God!" cried Carton. "What makes you think that?" CHAPTER XXVII. WE TRACK MR. KENNETH DOWSETT TO BOULOGNE. "It would occupy too long a time," I replied, "to make my theory thoroughly comprehensible to you. Besides," I added, glancing at Devlin, "it is a theory strangely born and strangely built up, and, in all likelihood, you would reject the most important parts of it as incredible and impossible. Therefore, we will not waste time in explaining or discussing it. Sufficient for us if we succeed in tracing this dreadful mystery to its roots and in bringing the murderer to justice. If I do not mistake, here comes the man I am waiting for." It was, indeed. Bill Foster, pioneered by the sharp lad who had engaged to find him.