The problem of the Intelligence Corps is much like that of putting the parts of a picture puzzle together. A line from a newspaper in one part of the world, a line from a newspaper in another taken in connection with a photograph, an excerpt from a letter found on a prisoner or a fact got from a prisoner by skillful catechism, might develop a valuable contributory item. The amount of information procured by either side about the other was only less amazing to the outsider than how it was obtained. Again, events revealed amazing ignorance. Most baffling and most secret of all branches is this, whose work is both gaining and conserving information, and just as professional, just as carefully prepared before the war as any other. A single instance illustrates how small a fact may be of value to the enemy. A certain well known "military expert" went out to British headquarters as a guest of a general. From a tower in the square of a small town, he watched a certain action. When he wrote his account of it, it was submitted to the general who was his friend; and the general carelessly passed one little statement which no Chief of Intelligence of any army would ever have passed and probably no correspondent of experience would have had the temerity to submit to the censor unless he wanted to be responsible for the death of men who were his hosts and his friends. For the writer stated that he saw the battle from this tower. Now the London papers reach Holland at four o'clock in the afternoon where they are seized promptly by the tentacles of the German Intelligence Service, which did not need to undertake any "picture puzzle work" on this occasion. It was plain as day that this tower must be used as an artillery observation post by the enemy. From there he could see the fall of shells from his batteries and know whether they were "on" or not. Out of the blue sky the next morning, came a German artillery concentration which brought the tower down like a house of cards, and many British soldiers billeted in the neighborhood were killed or wounded. In order to deepen the shroud of mystery over his side which baffles the enemy, many military men would undoubtedly make the press merely the herald of official bulletins. The British Admiralty carried out this system to the letter, as a navy may better than an army, in the resistance of the German submarine campaign. Thus the "Untersee-boots" came out from Kiel or Zeebrugge and disappeared in the mists of the North Sea with no message of how they had been destroyed when they never returned.