Page:Air Service Boys Over Enemy's Lines.djvu/53



" see the fiendish cleverness of the fellow who filed that stay!" Tom cried, as they all stared. "He filled the indentation his sharp file made with a bit of wax or chewing-gum of the same general color. Why, no one would ever have noticed the least thing wrong when making the ordinary examination."

"Then how did you manage to find it, Tom?" asked Jack, breathing hard, as he pictured to himself the narrow escape he had had.

"I suspected something of the kind might be done; so I ran my thumb-nail down each wire stay," came the answer. "And it turned out just as I thought."

"There may be still more places filed in the same way," suggested the other pilot, looking as black as a thunder-cloud; because such an act was in his mind the rankest sort of treachery, worthy of only the most degraded man.

"We will find them if there are," replied Tom, resolutely. "And when this thing is known I imagine there'll be a general overhauling of all the machines on the aviation field. One thing