In accordance with instructions already issued two of Fleck's men rushed for the front of the house, where with rifles ready they stood guard, while the others took cover in the shadow of one of the outbuildings a few feet distant from the rear entrance.

Apparently the plotters had been so long undisturbed in their mountain fastness that they had ceased to take even the most ordinary precautions against surprise. So far as could be discovered they had posted no guards over the aeroplanes and their deadly cargo, nor at either of the two doors to the main building. Nevertheless Fleck, as he crept stealthily up to the building with Carter at his side, took out his automatic and held it in readiness, and Carter followed his example.

There was no moon to reveal their movements as they approached the rear of the house. The evening was warm, and one of the windows had been left open. Noiselessly they crept up to it and looked within. It opened into a large room used as a dining hall, where they could see all of the men clustered about one of the tables, at the head of which sat old Otto Hoff with Frederic at his side. On the table before him was what appeared to be a rough map or blueprint. Frederic and five of the other men, Fleck observed, now wore aviation costumes.

"Comrades," old Otto was saying in German, "here is the course. You will have no difficulty in following it. Down the river straight till you see the lights of New York. You each understand what you are then to do, yes?"

"Certainly," three of the men, the pilots evidently, responded.

"Let us, to make sure," old Otto insisted, "once more rehearse it. Much there is at stake for the Fatherland. You, Anton and Fritz, will blow up the transports and the warships that guard them. Six great transports are lying there, ready to sail at daylight The troops went aboard to-night. We waited until it was signalled that it was so. You must not fail. The biggest of those transports once belonged to Germany. You must teach these boastful Americans their lesson. That one boat you must destroy for certain. Beside the transports to-night lie five vessels of war, two battleships, three cruisers. Them you must destroy also, if there is time. To each transport, two bombs, to each warship, two bombs--twenty you carry. If all goes well, two you will have left. With these do what you will, a house, a church, it matters not--anything to spread the terror of Germany in the hearts of these money-grabbing Americans."