In late April, 1918, I learned through secret-service channels that one of the large submarines of the _Deutschland_ class had left its German base on the 19th of April for a long cruise. On the 1st of May, 1918, I therefore cabled to the Department that there were indications that this submarine was bound for our own coast. A few days afterward I received more specific information, through the interception of radio despatches between Germany and the submarine; and therefore I cabled the Department, this time informing them that the submarine was the _U-151_, that it was now well on its way across the Atlantic, and that it could be expected to begin operations off the American coast any time after May 20th. I gave a complete description of the vessel, the probable nature of her cruise, and her essential military characteristics. She carried a supply of mines, and I therefore invited the attention of the Department to the fact that the favourite areas for laying mines were those places where the ships stopped to pick up pilots. Since at Delaware Bay pilots for large ships were taken on just south of the Five Fathom Bank Light, I suggested that it was not unlikely that the _U-151_ would attempt to lay mines in that vicinity. Now the fact is that we knew that the _U-151_ intended to lay mines at this very place. We had obtained this piece of information from the radio which we had intercepted; as there was a possibility that our own cable might fall into German hands, we did not care to give the news in the precise form in which we had received it, as we did not intend that they should know that we had means of keeping so accurately informed. As had been predicted, the _U-151_ proceeded directly to the vicinity of this Five Fathom Bank off Delaware Bay, laid her mines, and then, cruising northward up the coast, began her demonstration on the 25th of May by sinking two small wooden schooners. These had no radio apparatus, and it was not until June 2nd that the Navy Department and the country received the news that the first submarine was operating. On June 29th I informed Washington that another U-boat was then coming down the west coast of Ireland, bound for the United States, and that it would arrive some time after July 15th. Complete reports of this vessel were sent from day to day, as it made its slow progress across the ocean. On July 6th I cabled that still another U-boat had started for our coast; and the progress of this adventurer, with all details as to its character and probable area of operations, were also forwarded regularly. From the end of May until October there was nearly always one submarine operating off our coast. The largest number active at any one time was in August, when for a week or ten days three were more or less active in attacking coastwise vessels. These three operated all the way from Cape Hatteras to Newfoundland, attempting by these tactics to create the impression that