"The best thing we can do is to ride for Tirlemont and make enquiries there," suggested Rollo, handing the dispatch back to his chum. "As regards concealing the paper, we must place it somewhere where we can get at it easily. I have it: we'll stow it in your petrol tank; the stuff won't injure the paper or interfere with the writing, and if things came to the worst, you can whip it out and set fire to it." Accordingly the dispatch, cleverly rolled, was placed inside the gauze strainer to the patrol tank, and the metal cap replaced. Five minutes later the two motor-cyclists were buzzing along the congested road at a modest twenty miles an hour, dodging between the lumbering transport wagons and the military vehicles with an agility that surprised themselves. Presently, as they struck towards the rear of the long lines of troops, the road became less encumbered and speed was materially increased. Soon the pace reached nearly forty miles an hour, for the highway was fairly broad, and ran as straight as a Roman road as far as the eye could reach. "Puncture!" shouted Kenneth, as the front wheel of his cycle began to slither and bump upon the _pavé_, the machine running nearly fifty yards before he brought up and dismounted. A hasty examination showed that a rusty iron nail, quite six inches in length, had penetrated the tread of the tyre, while to make matters worse its point had worked out close to the rim. The offending piece of metal, catching against the front forks, had already enlarged the hole in the tread till it became a slit nearly half an inch in length. "Don't wait," he continued, as he unscrewed the cap of the petrol tank and produced the dispatch. "Take this, and hurry on. I'll patch this up and follow. If you can, wait for me at Cortenaeken till two o'clock." "Right-o!" assented Rollo. "You can manage all right?" "I can't ask you to bear a hand if I don't," replied Kenneth. "I'll make a job of it somehow. Good luck!" Rollo was off. Kenneth stood beside his crippled steed and watched his friend's receding figure out of sight; then taking out his repair outfit he began his task. It was a long job. The cover, being practically a new one, was an obstinate one to remove. It had to be patched with canvas, while the double puncture in the inner tube took a considerable time to clean and prepare. While he was waiting for the solution to get "tacky", a peculiar buzzing sound greeted his ears. "Aeroplanes!" he muttered. "Whose, I wonder?" He looked upwards. The sun shining in a cloudless sky dazzled his vision. He put on his tinted goggles, which during the repair operations he had removed. Then he saw, perhaps three thousand feet above him, a large Zeppelin moving in a westerly direction. He watched it with a sort of contemptuous interest.