The naval officers who expressed fears that, under the shipping conditions prevailing in 1917, such a brilliant performance could not possibly be carried out in time to avoid defeat, merely gained a reputation for timidity and lack of resourcefulness. When the First Lord of the Admiralty, Winston Churchill, in 1915 declared that the British fleet would "dig the Germans out of their holes like rats," his remarks did not greatly impress naval strategists, but they certainly sounded a note which was popular in England. One fact, not generally known at that time, demonstrated the futility of the whole idea. Most newspaper critics assumed that the barrage from Dover to Calais was keeping the submarines out of the Channel. That the destroyers, aircraft, and other patrols were safely escorting troopships and other vessels across the Channel was a fact of which the British public was justly proud. Yet it did not necessarily follow that the submarines could not use the Channel as a passage-way from their German bases to their operating areas in the focus of Allied shipping routes. The mines and nets in the Channel, of which so much was printed in the first three years of the war, did not offer an effective barrier to the submarines. This was due to various reasons too complicated for description in a book of this untechnical nature. The unusually strong tides and rough weather experienced in the vicinity of the Straits of Dover are well known. As one British officer expressed it at the time, "our experience in attempting to close the Strait has involved both blood and tears"--blood because of the men who were lost in laying the mines and nets, and tears because the arduous work of weeks would be swept away in a storm of a single night. In addition, at this stage of the war the British were still experimenting with mines; they had discovered gradually that the design which they had used up to that time--the same design which was used in the American navy--was defective. But the process of developing new mines in wartime had proved slow and difficult; and the demands of the army on the munition factories had prevented the Admiralty from obtaining a sufficient number. The work of the Dover patrols was a glorious one, as will appear when all of the facts come to public knowledge. But in 1917 this patrol was not preventing the U-boats from slipping through the Channel. The Straits of Dover, at the point where this so-called barrage was supposed to have existed, is about twenty miles wide. The passage-way between Scotland and Norway is 250 miles wide. The water in the Channel has an average depth of a few fathoms; in the northern expanse of the North Sea it reaches an average depth of 600 feet. Mining in such deep waters had never been undertaken or even considered before by any nation. The English Channel is celebrated for its strong tides and stormy weather, but it is not the scene of the tempestuous gales