"Absolute silence in regard to your missions. No conversation with minor officials but only with the respective heads of departments or to whomever you are sent. You will make no memoranda nor carry written documents. You will never discuss your affairs with any employee in the Service whom you may meet. You are not likely to meet many. It is strictly against the rules to become friendly or intimate with any agent. You must abstain from intoxicating liquors. You are not permitted to have any women associates. You will be known to us by a number. You will sign all your reports by that number. Always avoid telephoning, telegraphing and cabling as much as possible. In urgent cases do so, but use the cipher that will be supplied to you." He went on to give numerous other minor details and instructions, elaborating the system, but which might prove wearisome here. I was in his office all the forenoon, and when he ushered me out I half expected to be called into von Tappken's presence to be sent on my first mission. Instead of that, I had to wait five months before I was given my first work and an exceedingly unimportant thing it was. During those five months I was kept at a steady grind of schooling in certain things. Day after day, week after week, I was grounded in subjects that were essential to efficient Secret Service work. Broadly, they could be divided into four classes--topography, trigonometry, naval construction and drawing. The reasons for these you will see from my missions. My tutors were all experts in the Imperial Service. A Secret Service agent sent out to investigate and report on the condition, situation, and armament of a fort like Verdun in France must be able to make correct estimates of distances, height, angles, conditions of the ground, etc. This can only be done by a man of the correct scientific training. He must have the science of topography at his finger tips; he must be able to make quick and accurate calculations using trigonometry, as well as possessing skill as a draftsman. In my mission to Port Arthur, where I had to report on the defenses, I found this training invaluable. The same applies to the subject of naval construction. Before entering the German Secret Service, I certainly knew the difference between a torpedo and a torpedo boat destroyer, but naturally could not give an accurate description of the various types of destroyers and torpedoes. My instructor in this subject was Lieutenant Captain Kurt Steffens, torpedo expert of the Intelligence Department of the Imperial Navy. After a month of tutelage under him, I was able to tell the various types of torpedoes, submarines, and mines, etc., in use by the principal Powers. I could even tell by the peculiar whistle it made whether the torpedo that was being discharged was a Whitehead or a Brennan.