It is a well-known fact that long before the famous Tank--that atrocious and unfair weapon which the English used, contrary to the laws of the Hague Convention--came upon the scene, secret experiments were being made. Potsdam had heard of these, and I had received instructions to prosecute my investigations with the greatest vigour. Naturally rumours were rife, and there were many mares’ nests before, by a lucky chance, our good Klein heard of this experimental camp. I had no difficulty in concocting a story for Mister Haynes. My suggestion was that he should write an article on the marvellous mechanical contrivances which the genius of Britain had brought into being and I despatched him, with Klein, hot upon the scent to investigate and report. They left by the night train from Paddington and I saw them off. Klein was very decorous, the picture of an English gentleman in his check cap and his long travelling coat, his neat-gloved hands and his English magazine, and Mister Haynes, as untidy as ever, curled up in the corner of the carriage and, I should imagine, asleep before he left the station. What happened was told me by Klein on the telephone. It was a happening so disconcerting, so mysterious, that I must confess that I regarded the unlooked-for outcome of this adventure with more than ordinary disquietude, even had there not been the more terrible sequel. They reached their destination, a small West Country town, in the early hours of the morning and went to their hotel where they were joined by Posser, who was working with Klein, and who, deeply conscious of the importance of finding out details of this particular machine, had been spending that day in making judicious inquiries. They had breakfasted together the next morning, when, of course, no mention was made of the camp or the new armoured car, Klein introducing Posser as his secretary. I might explain that Klein was posing as a Swedish mining engineer who had a patent for sale connected with coal haulage. I had sent Mister Haynes on the same train and in company with Klein, on the pretext that, as Mr. Klein was a friend and was going to the same town, they might travel together and that Mr. Klein might possibly give my reporter certain introductions which would be useful. Mister Haynes spoke about his mission quite openly, though Klein advised him, laughingly, not to mention his business if he wanted to secure the information he required. Apparently Mister Haynes met with little success, and came back to the hotel to dinner and said that all his efforts to induce any of the soldiers attached to the camp to give him information or to secure admission had been fruitless.