Now he brought the monoplane around in a great sweep and flew straight over the woods. But, though Frank looked down through powerful navy night glasses, of the sort that are used for look-out duty at sea, he could see nothing. "Clasp them around my head--so," said Greene. "See the trick? All right! Now I'll have a look. There's another pair in my pocket--use those for yourself." But if the Germans were there, they were concealing their presence with a good deal of care and skill. "Have to go lower, then," decided Greene. "Get ready! We'll shoot the chutes now." He pointed the monoplane straight down, cut out his motor, and glided earthward in a glorious volplane, the most wonderful sensation that even flight, with all its wonders, can afford. When the earth seemed about to come up and hit them, though it was still actually a good five hundred feet below, he caught the machine, righted it, and started the motor again. Then he had to fly back until he was again directly over the woods, and once more, while the monoplane moved very slowly, they peered down. But still there was no sign. "Humph!" said Greene. "If they were supposed to be anything but Germans, I'd say you'd told us a cock and bull story, young 'un! English troops, or French, would show some sort of a light. Some fool would take a chance to get a smoke. But these Germans! They're not men--they're machines. They'll obey orders that officers wouldn't take the trouble to give in any other army. We'll have to make sure. Up we go again!" Frank could not see how going up would make it possible for them to get the information that coming down hadn't afforded. But he said nothing, because he had come to feel by this time that when Captain Greene did a thing he had a perfectly sound reason for his action. Nor was he wrong. Once more they climbed in a high spiral curve until they were higher than they had been before. For the first time, Frank now felt a peculiar ringing in his ears. He mentioned it, and Greene laughed. "Pressure," he said. "You'll get used to it! Lord, sometimes I've felt as if my head would burst when I started to climb. But it doesn't last long. Feel in the seat there beside you, at your left. There ought to be a big electric torch." "Here it is! I've got it, sir," said Frank, a moment later. "All right. Touch the button at the end. Let's see if it lights up properly." It did, decidedly, for the result was a blinding glare. "Pretty powerful, isn't it?" said Greene. "It's used for signalling, you see. Flash the light, and you can reproduce Morse perfectly. When you're high up it can be seen a long way, too. Now hold it straight down and flash it, then give a steady glare. Let us see if we cannot draw anything."