I briefly explained the procedure and the method by which our agents would be identified. Every German agent would prove his bonâ fides by producing three used postage stamps of Nicaragua. It is a simple method of identification, for there is nothing treasonable or suspicious in a man carrying about in his pocket-book a ten, twenty or a fifty centime stamp of a neutral country. I sent Emil Stein away to Portsmouth and instructed him to make contact with sailors of the Fleet, especially with officers. Besser was dispatched to a West Coast shipping centre to report on all the boats which left and entered. I sent Kahn and his family on a motor-car tour to the East Coast with instructions to find out what new coast defences were being instituted. “You must exercise the greatest care,” I said; “even though these English are very stupid, they may easily blunder into a discovery. Make the briefest notes of all you see and hear and only use the Number 3 code in case of urgent necessity.” We finished our dinner and we drank to “The Day” and sang under our breath “Deutschland über alles” and separated, Koos coming with me. Koos was a staff officer of the Imperial Service, and though he was not noble, he was held in the greatest respect. He was a fine, handsome fellow, very popular with the girls, and typically British in appearance. His English was as good as mine, and that is saying a great deal. I sent him to Woolwich because in his character as an American inventor--he had spent four years in the States--he was admirably fitted to pick up such facts as were of the greatest interest to the Government. I did not see Koos for a few days and in the meantime I was very busy arranging with my couriers who were to carry the result of our discoveries through a neutral country to Germany. The system I adopted was a very simple one. My notes, written in Indian ink, were separately photographed by means of a camera. When I had finished the twelve exposures, I opened the camera in a dark room, carefully re-rolled the spool and sealed it so that it had the appearance of being an unexposed pellicle. I argued that whilst the English military authorities would confiscate photographs which had obviously been taken, they might pass films which were apparently unused. I had arranged to meet Koos on the night of August 17th, and made my way to the rendezvous, engaging a table for two. I had hardly seated myself when, to my surprise, Koos came in accompanied by a very pretty English girl. He walked past me, merely giving me the slightest side-glance, and seated himself at the next table. I was amused. I knew the weakness of our good Koos for the ladies, but I knew also that he was an excellent investigator and that he was probably combining business with pleasure. In this I was right. The meal finished--and the innocent laughter of the girl made me smile again--and Koos walked out with the girl on his arm.