"A good spin will be almost as refreshing as a few hours' sleep, Rollo," said Kenneth, as the two chums made their way to the place where their motor-cycles were stored, protected by three feet of concrete and six feet of earth from hostile shells. "With plenty of excitement thrown in," added Rollo. "We'll have a difficulty to dodge those shells as we get clear of the fort, I'm thinking." "Rush it and trust to luck. We'll do it all right," declared Kenneth optimistically, as he hurriedly overhauled his cycle and proceeded to warm up the engine. It was a tricky business getting out of the fort, for the sunken lane that wound through the extensive glacis was littered with debris of exploded shells. There were deep holes in several places, while at various points the effect of the German projectiles was evident by the fact that the approach to the fort was choked by landslides. Thrice the lads had to dismount and push their cycles over obstacles, to the accompaniment of the dull crash of the shells, some of which burst unpleasantly near. All the while, although not a defender was visible, the armoured cupolas were appearing and disappearing with the regularity of clockwork, sending out their iron hail upon the pontoons which the German engineers were constructing to replace the broken bridges at Visé and Argenteau. "All out!" exclaimed Rollo as they reached the open road. With throttle well open and spark advanced, both motor-cycles bounded forward. The pace was terrific. At times the riders were almost jerked from the saddles as their steeds leapt across the irregularities on the surface of the _pavé_. The lads could no longer hear the thunder of the guns: it was drowned by the roar of their exhausts. The wind shrieked past their ears, grit flew in showers, a cloud of dust followed in their wake. Suddenly they saw a large silvery-grey object swoop down about a quarter of a mile ahead, close to the outskirts of the village of Jupille, which had been abandoned by the terrified inhabitants. The riders recognized it as one of the German Taubes that had been aggressively active during the operations by locating the position of the Belgian trenches. The monoplane was in difficulties. It took all the skill of the pilot to prevent it from making a nose-end dive to earth. With superb presence of mind he managed to restore the disturbed equilibrium and to bring the Taube to rest without much damage. Bringing his motor-cycle to a halt, Kenneth dismounted and placed his mount on its stand. Rollo did likewise. "What's the game?" he asked as his companion unfastened the flap of his holster. "We'll collar those fellows," declared Kenneth resolutely "They must not get away." "But the dispatch?" "This is more important, I guess. See, those fellows are already setting things to rights. Before any of the Belgian vedettes can come up they will be off again."