"Well, you see," resumed Mark, "the British Army will be crossing to France. You don't suppose that ever so many of our transports—big liners crowded with troops—will be allowed to go over by themselves, at the risk of being sunk by German submarines? They've got to be protected on both flanks. I expect they'll steam across through quite an avenue of cruisers and destroyers."
Later, when Mark was saying good-night before going sleepily to bed, there was a ring at the front-door bell.
"Master Mark is wanted," the parlourmaid announced agitatedly. "There's a policeman and a lot of soldiers."
No longer sleepy, Mark hurried into the hall, where he found Constable Challis, Mr. Bilverstone, and two men in khaki.
"What's up?" he cried, seeing that the two soldiers were armed with rifles and fixed bayonets. "Are the Germans coming?"
"We want you to go with us," Arnold Bilverstone explained. "Get on your overcoat, and bring your electric torch. We're going to make a raid on Herr Hilliger's pigeon-loft."
Mark was quickly ready to march off at the head of the company. As they filed into the Sunnydene ground they saw that the house was in total darkness.
Leaving one of the sentries posted outside the stable yard, Mr. Bilverstone led the way round to the rear of the outhouses, where he posted the second sentry. Mark crossed the tennis-court, dodged under the fruit trees, and crawled through the hatch door which he had left unfastened. Mr. Bilverstone and Constable Challis followed him through the stable and into the garage. They mounted one by one into the loft. Mark flashed his torchlight along the floor, up into the rafters, and again along the floor. Then he stooped and picked up the stub of a cigarette, sniffed at it and shook his head.
"Somebody has been here!" he cried. "The end of this cigarette's still wet."
He went beyond the partition and began to search. But his search was in vain. The maps, the electric signalling-lamp and coloured bulbs, the model of the submarine, the spool of paper, the elastic bands—all had been cleared away. Nothing remained to show that the place was more than an abandoned pigeon-loft.