They emerged from the shadow of the wall, and reached the foot of the stairway that led to the roof. The door at the top was open, as the moonlight was shining down, and Wharton boldly led the way, walking on tiptoe, his automatic in his hand. At the open door John and Carstairs crowded up by his side, and three pairs of eyes peeped out at once.
They saw two men on the roof both with their backs turned to them. One was the operator of the wireless, sitting on a camp stool, working the instrument. The other, in an officer's uniform, was dictating messages. John surmised that they were talking with a station to the eastward, where some lofty ranges of hills ran.
But Wharton was the most deeply stirred of the three. The spark in his eye was enlarging and glowing more brilliant, and a great resolve had formed in his mind.
"There's nothing that we can do here," said Carstairs. "We'd better go at once."
"We're not going," said Wharton in a fierce whisper. "I can use the wireless, and that's just the instrument on which I wish to exercise my skill. I've heard enough to know they're not talking in code."
"Wharton, you are mad!" said John.
"If so, I'm mad in a good cause. Inside of ten minutes some German general will be hearing remarkable news from this station."
"I tell you again you're mad."
"And I tell you again I'm not. I'm a crack wireless operator and this is my chance to prove it. I'm going up there. All who are afraid can turn back."
"You know that if you're resolved to go mad we'll go mad with you. What do you want us to do?"