"It was a man slipping across from one shadow to another, as sure as anything," breathlessly admitted the second watcher.
"No fellow would act that way unless he wanted to keep from being seen, would he?" asked Harry.
"You're right there. Oh! I saw a second one follow him then, Harry!"
"Yes, there's a pair of the creepers. That makes me believe more than ever they were aboard one of those bombing planes, Tom."
"It might be they fell when one of the Hun raiding planes was knocked out," suggested the other, as an idea struck him. "Only one went down in flames, I remember now. Those in the other may have managed to make a safe landing, and bent on hitting us a crack before trying to get back to their lines, they've crept into the camp here."
"Carrying some grenades, I'd like to wager, which they can use in kicking up a big row, under cover of which they'll scoot off," Harry went on.
"We must put a peg in their plans then," whispered Tom. "It'd be a shame to let them do what their pilots failed in, and blow up a part of our hangar field here."
"If they do they'll go up with the planes then!" Harry gritted between his set teeth. "Come, let's move on and corner the Huns!"
