Roque, by which name, it might be mentioned, he was not known in this heart of the empire, soon demonstrated to his charges that he was the man higher up by his manner of getting about, and the high cost of living had no worries for him.

"Who'd have thought that we would be hitched up to a ten-time winner like this?" Billy was content for the time being to be allied with power.

Among the many who answered the summons of Roque in the intelligence bureau, the young aviators were most interested in a score of blond, blue-eyed, well-set-up Saxons, renowned as Zeppelin navigators, who were destined to guide the "terrors of the air" in furtherance of another raiding plan taking form in the fertile brain of the eminent promoter of trouble for the enemy.

While the boys had faith only in the heavier-than-air machines, they conceded that the risk taken by the Zeppelin crews entitled the latter to brush elbows with the crack flyers of the other kind of bird craft. It was also true that when a Zeppelin got anywhere it was a tremendous factor in war. And it was no question but that the Fatherland had gone Zeppelin mad.

Woe betide the hostile airmen who dropped the bomb on the Zeppelin works at Friedrichshaven if Roque had the means of catching them. It was only another score that he had marked up against Ardelle, whom the master agent of the empire charged with planning this destructive performance.

"Roque said he was going to show us where these gas cruisers grow," Henri advised Billy one evening, getting this news while his chum was engaged in an argument with a Zeppelin worker.

"Something I've been wanting to see," exclaimed Billy. "I owe something to a Zeppelin, even if it is like a balloon."

This last was a sort of side swipe at the man who had been on the other side of the argument.

"There is one thing sure, these dirigibles can't camp out." This was Billy's first remark in Friedrichshaven.

He was peering into a big steel-framed shed with a glass roof which housed one of these grim engines of the air—a great cylinder flanked by platforms. This newest of the huge airships was about the length of a first-class battleship, and the opinion of the young aviator that it could not drop anywhere and everywhere like the aëroplanes he drove was not a prejudiced one.