"Now," exclaimed Froissart, "I will tell to you, my friend Dawson, the true _histoire_ of my exploits so tremendous and unapproachable. I reached the station at Plymouth at ten hours, my spy was upon the platform. I knew him, for those who had kept him under watch had informed me of him. I had with me two police officers _en bourgeois_, what you call plain clothes, and I distributed them with the acumen of a strategist. It was _un train à couloir_. The spy disposed himself in a compartment. I placed one of my officers in the same compartment with him, the other in the compartment _contiguée_ towards the engine, myself in that _à derrière_. He was thus the meat in our sandwich. If he passed into the corridor and walked this way or that he was seen by me or by my man in advance; all his movements while within his own compartment were supervised every moment. So we travelled. He did himself well that spy so atrocious. He partook of his _déjeuner_ in the _buffet du train_, and we all three took our _déjeuner_ there also. That was the last meal of which I ate before this my supper here. The journey was without incident, but when he arrived at Waterloo the trouble began. He was not taking risks, that spy. He knew not that he was under watch, but he took not risks. He began to perform a voyage designed to throw any man, except one of the vigilance and resource of Froissart, completely off his track. I was not learned in your Métropolitain before this day, but now I know your Tubes as if a map of them were printed in colours upon my hand. At Waterloo that spy, so astute, burrowed into the earth and entered a train of the railway called Bakerloo, in which he journeyed to Golder's Green. Then he crossed a _quai_ and returned to the town called Camden. Again he descended, passed through tunnels, and emerging upon another _quai_ proceeded to Highgate. All the while we three followed, not close, but so that he never escaped from under our eyes. At Highgate he turned about and returned to Tottenham Court Road. Thence he departed by another line to the Bank, and, rising in and _ascenseur_, emerged upon the pavements of your City. He looked this way and that, not perceiving us who watched, walked warily to the Lord Maire's station of the Mansion House, boarded the District Railway, and did not alight till Wimbledon. It was easy to follow, but my friend, the billets, the tickets, were _une grande difficulté_. I solved the problem of tickets by my genius so _superbe_. We at first tried to take them, but _après_ we abandoned the project so hopeless and travelled _sans payer_. When asked at the barriers or in the lifts, we offered pennies, and the men who collected took them joyfully, asking not whence we came. It was _une procédée très simple_. It is possible that these wayward uncounted pennies dropped into their own pockets. They rejoiced always to receive them. From Wimbledon we returned to Earl's Court, and then, descending by an