Preparations to repel just such an invasion had been made in the great city.
Ardelle must have gotten his warning across, but the coast towns failed to heed it.
The Roque machine kept its speed when the balance of the fleet checked flight at Amesland. The secret agent was bound for Cuxhaven, doubtless to plan another tiger spring at the foe. He was all for air campaigning these days.
"You will witness the sight of your lives, you young cyclones, before last night's mist of the North Sea dries in your hair."
This significant remark on Cuxhaven docks set the boys in the highest state of expectancy. It was seldom that Roque billed anything ahead of time, and surely something extraordinary must be in the wind.
Three days later, from a dizzy height, they witnessed a sky battle without parallel in military annals, and which dimmed the memory of any of their previous remarkable experiences in the war zone.
The French coast town of Dunkirk, to which the boys had on a happy day gone by been delivered by submarine and taken away in a seaplane, was the ground center of this spectacular conquest of the air—the first of its kind in the history of the world.
Twenty hours earlier a fleet of British seaplanes had bombarded the Belgian port of Zeebrugge, held by the Germans, news of which had soon after reached the mystery man, Roque, by way of one of the innumerable channels of communication with which he kept himself constantly in touch.
The German bird craft suddenly appeared over Dunkirk like a flock of gigantic sea gulls.
Explosive missiles fell as fiery hail upon the town. The tocsin sounded in the high tower of Dunkirk church, and the blue and white flag of the town was run up.