Mark realised that, if from here he could see that ruby gleam, it was certain that the crew of the lightship could equally well see the flash of his electric torch. Was it not possible that Heinrich Hilliger had used this hole in the loft door through which to flash his signals? Mark covered the hole by hanging his cap on a nail just above it.
Then he turned and closed the trap in the floor. It made more noise in falling than he had intended. Whether it was the displacement of air or his own fancy, there seemed to be a corresponding sound down below, as if another door had been suddenly shut, and as if the key of that other door had been turned in the lock.
"I suppose I'm a bit nervous," he said to himself. "It couldn't have been anything." He drew out his torch, pressed the switch, and turned the shaft of light upon the partition beyond which Hilliger's pigeons were kept. The key was in the door. Feeling like a guilty burglar, he turned it and entered, shielding the light from the open space in the gable by which the pigeons flew in and out.
There were no pigeons here now. The coops and perches were empty. He supposed that Herr Hilliger had taken the birds away with him, to use them in carrying secret messages back to England; although, as yet, there was no proof that Herr Hilliger had ever actually used any of his pigeons for this purpose.
Mark made a rapid survey of the untidy loft, with its lumber of old harness, rusty garden tools, bundles of sacking, broken fishing-rods, and discarded cricket bats. On a low shelf were some model yachts with torn sails and tangled rigging. He looked at the rough model of a steam trawler. The boat was curiously constructed with a boxed-in and bottomless well. Inside this well there was a crude model of a submarine. Some one—Max Hilliger, perhaps—had evidently attempted to invent a device by which a real submarine might be hidden within the casement of a larger vessel, thus enabling it to be brought close to an enemy without being discovered. The idea was ingenious, but obviously not practical.
In a corner cupboard he discovered a box of electric light bulbs of various colours. The sight of these led him to search for electric wires. He saw none; but what he did find was a portable electric lamp coiled round with a wire so exceedingly long that, as he estimated, the switch might be worked here in the loft while the bulb could be cunningly planted amongst the gorse bushes halfway down the cliff, there to flash its signals of coloured light.
Mark wondered if he should take the lamp away with him, but decided to leave it untouched. If as he believed, Herr Hilliger was already on his way back to Germany, and if Max were drowned, there could be no more risk of their communicating with the enemy.
He turned his torch upon the long trestle table at the far end of the loft. It was littered with feathers and grain, and thick with dust. But in the midst of the litter were several things which he considered it his duty to examine. The first article he touched was a match-box, half full of very small elastic bands. Beside it was a spool of thin, narrow paper.
"Here's proof enough!" he reflected with satisfaction. For he recognised the paper and the elastic bands as being precisely similar to the material found on the leg of the pigeon shot by Darby Catchpole from the deck of the What's Wanted.
For a little while longer he continued his search. From a pile of old newspapers and tattered books, he idly drew forth a long, tin cylinder, thinking at first it was a telescope case. The lid had been jammed on crookedly, and he had difficulty in pulling it off with the help of his knife. When he succeeded at last in opening the canister, he saw that it contained several tightly-rolled sheets of paper. He spread them out on the table. They were maps, plans, and charts, very carefully drawn.