"Jolly comfortable quarters," I remarked, glancing round. "I called here before, but you were out." "Yes, so sorry!" he exclaimed. "Sit down and have a cigar," and he handed me a box of most excellent weeds. "Well," exclaimed the smart young fellow who was the confidential secretary of Sir Albert Oppenheim, "I'm really glad to see you again, Mr. Holford. That was a most mysterious incident at Sussex Place the other evening," he added. "I'm still convinced that somebody was in the house. The Professor's furnace was alight, you recollect, and the laboratory door stood open." "Langton has told me all about it," remarked the doctor in a deep voice; "very curious, it seems." "Most extraordinary," I declared, "and the more so that Merli, the butler, should have suddenly disappeared. The other day I met him in Rome." "Met Antonio!" gasped Ethelwynn's lover, staring at me in amazement. "Have you been to Italy?" "Yes. I told him of our search, but he declared himself ignorant of everything, though he admitted having seen you passing through the buffet at Calais-Maritime." "What is he doing in Rome?" "I have no idea; I was there in a vain endeavour to recover my lost wife. She has been misled by a forged telegram purporting to come from myself, and is somewhere on the Continent. Where, however, I cannot tell." "You've lost your wife, eh?" asked the doctor, glancing strangely across at his companion, I thought. His face was dark and aquiline, his shoulders sloped. He was not a man to be trusted. "You think she's been tricked?" he added. "Why?" "Ah, at present I can form no theory as to the motive. If I could I might perchance discover the person responsible for her disappearance," and I briefly told him of my frantic journey to the Italian capital. "And now I am going to Strassburg tomorrow," I added. "Why to Strassburg?" inquired Doctor Flynn, regarding me fixedly with those keen eyes of his. "Because Professor Greer is there, and I have an idea that he can tell me something." "The Professor is no longer there," was Langton's quick interruption. "Half an hour ago I spoke to Ethelwynn on the telephone, and she told me that she had just heard by telegraph from her father that he had left for Linz on his way to Hungary." My heart fell within me. Evidently my telegram signed Kirk had scared the man passing himself off as the Professor. "But I might go on to Linz, or catch him up somewhere in Hungary," I suggested. "It would be futile, my dear fellow," said Langton. "Why?" "Well, just at present Professor Greer wishes to be left entirely alone by his friends." "But there must be some reason," I cried, for there seemed on every hand to be a conspiracy of silence again me. "There is a reason," replied the young man in a low, calm voice, "one which, however, seems mysterious." "Ah!" I cried. "Then even you are mystified by these strange happenings?"