"About a week ago. But what's all this about Conrad you're asking, Roque? I'll have him in, and you can judge if he is worth a moment's notice in this kind of affair." Spitznagle started for the kitchen door, Roque at his heels. "Conrad, Conrad," called Spitznagle. "Conrad" had flown, leaving nothing behind him but his rheumatism and a dingy apron. "Yell till you're hoarse, you fathead," raged Roque, "and the cows will come home from nowhere before you get an answer." While Spitznagle was staring into vacancy, Roque stormed back into the dining-room and announced: "We've been the dupes of that spy Ardelle. Nobody but he could have gotten away with a venture like this. But" (gritting his teeth), "I'll beat him yet. I say, Vollmer" (turning to the aërial recorder now minus his records), "you have the whole thing in mind and we'll strike while the iron is hot. We may outride the warning, for he can't get it flashed from this coast." The man in the cloak came to the front on this proposition. "The word is 'immediate,'" he proclaimed. A speedy departure was in order, and Roque crooked a finger at the young aviators, bidding them follow. "You are going to be mighty useful, my flying friends," he said, "and you'd better be." There was grim emphasis in these last words. At noon the next day the boys were again tramping around after Roque in Cuxhaven. The character of "Dr. Blitz" was no longer in the play. Roque was trimly set up as an aviation lieutenant, and it was really wonderful how easily he merged into each part he assumed. "Students" no longer, Billy and Henri were happy in resuming their flying clothes. "Best becomes our style of beauty," as Billy would have it. There seemed to be some unforeseen reason for delay, as the aërial expedition did not start forthwith, as intended. Indeed, it did not start from Cuxhaven at all. It might have been that Ardelle's theft of the guide records had put a spoke in the German wheel, but as to that the boys could only hazard a guess. It was on the twentieth day after the adventure in the house of Spitznagle that the young aviators again had the opportunity of operating a seaplane with Roque as directing passenger, and the uninterrupted flight brought them to the island of Amesland, for though Cuxhaven was counted as the airship base, it evidently was the intent to project the return attack on the English coast from the out-to-sea point before named. What an array of the warcraft of the "upper deep"--the great dirigibles, seaplanes, destroyer, artillery spotter and scout aëroplanes. The boys were in their element. Even Roque had a smile for their enthusiasm. It was not the war spirit that animated Billy and Henri--they reveled in the show as airmen delighted with the life.