"Yes, Mr. Jacox," the girl said. "I have come to thank you. I was first approached by the young Italian while crossing Richmond Bridge one day, and later on he introduced me to his sister, who lived in St. Margaret's. On the afternoon when I was induced to go there I was given something in my tea which at once rendered me unconscious. When I recovered, I found myself lying in a coffin secured to rings inside, while a villainous old man, a bearded German, and an Italian woman were about to screw down the lid. I screamed, but they took no notice, until in fear I fainted. Ah! shall I ever forget those horrible moments? I was alone, helpless in the hands of those fiends, all because I had allowed myself to become attracted by a stranger! They held me there for days, trying to learn from me the secret of my father's discovery. But I would tell them nothing. Ah! how I suffered, believing every hour that they would close down that lid. Then the brutes, finding me defiant, and believing that no one was aware of their existence, hit upon another device--sending a false telegram to my father from Liverpool, and thus taking him away from the house in order to be afforded a clear field for their investigations. Of this I, of course, knew nothing until your friends entered the house forcibly with the police and found me still imprisoned--ah! yes! ready for death and burial." And then the strange old Professor, stepping forward, seized my hand warmly in his, saying: "To you and your two good friends, Mr. Jacox, the country owes a great and deep debt of gratitude. I was foolish in disregarding your timely warning, for my dear daughter very nearly lost her life, because the blackguards knew she had assisted me in my experiments and had made the notes at my dictation, while Britain very nearly lost the secret upon which, in the near future, will depend her supremacy at sea." CHAPTER VII THE SECRET OF THE IMPROVED "DREADNOUGHT" The road was crooked and narrow, and the car was a nondescript "ninety," full of knocks and noise. By appointment I had, for certain reasons that will afterwards be apparent, met, in the American Bar of the "Savoy," two hours before, the Honourable Robert Brackenbury, the dark, clean-shaven young man now driving, and he had engaged me, at a salary of two pounds ten per week, to be his chauffeur. I had driven him out through the London traffic, until, satisfied with my skill, he had taken the wheel himself, and we were now out upon the Great North Road, where he had a pressing engagement to meet a friend. Beyond Hatfield we passed through Ayot Green, and were on our way to Welwyn, when suddenly he swung the powerful car into a narrow stony by-road, where, after several sharp turns, he pulled up before a pleasant, old-fashioned, red-roofed cottage standing back in a large garden and covered with ivy and climbing roses.